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Lonare S, Rode S, Verma P, Verma S, Kaur H, Alam MS, Wangmo P, Kumar P, Roy P, Sharma AK. Characterization of AICAR transformylase/IMP cyclohydrolase (ATIC) bifunctional enzyme from Candidatus Liberibacer asiaticus. Biochim Biophys Acta Proteins Proteom 2024; 1872:141015. [PMID: 38615986 DOI: 10.1016/j.bbapap.2024.141015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/23/2024] [Accepted: 04/09/2024] [Indexed: 04/16/2024]
Abstract
The bifunctional enzyme, 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) transformylase/inosine monophosphate (IMP) cyclohydrolase (ATIC) is involved in catalyzing penultimate and final steps of purine de novo biosynthetic pathway crucial for the survival of organisms. The present study reports the characterization of ATIC from Candidatus Liberibacer asiaticus (CLasATIC) along with the identification of potential inhibitor molecules and evaluation of cell proliferative activity. CLasATIC showed both the AICAR Transformylase (AICAR TFase) activity for substrates, 10-f-THF (Km, 146.6 μM and Vmax, 0.95 μmol/min/mg) and AICAR (Km, 34.81 μM and Vmax, 0.56 μmol/min/mg) and IMP cyclohydrolase (IMPCHase) activitiy (Km, 1.81 μM and Vmax, 2.87 μmol/min/mg). The optimum pH and temperature were also identified for the enzyme activity. In-silico study has been conducted to identify potential inhibitor molecules through virtual screening and MD simulations. Out of many compounds, HNBSA, diosbulbin A and lepidine D emerged as lead compounds, exhibiting higher binding energy and stability for CLasATIC than AICAR. ITC study reports higher binding affinities for HNBSA and diosbulbin A (Kd, 12.3 μM and 34.2 μM, respectively) compared to AICAR (Kd, 83.4 μM). Likewise, DSC studies showed enhanced thermal stability for CLasATIC in the presence of inhibitors. CD and Fluorescence studies revealed significant conformational changes in CLasATIC upon binding of the inhibitors. CLasATIC demonstrated potent cell proliferative, wound healing and ROS scavenging properties evaluated by cell-based bioassays using CHO cells. This study highlights CLasATIC as a promising drug target with potential inhibitors for managing CLas and its unique cell protective, wound-healing properties for future biotechnological applications.
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Affiliation(s)
- Sapna Lonare
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Surabhi Rode
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Preeti Verma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Shalja Verma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Harry Kaur
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Md Shahid Alam
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Padma Wangmo
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Pravindra Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Partha Roy
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247 667, India.
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Abstract
The bacterium responsible for a disease that infects citrus plants across Asia facilitates its own proliferation by increasing the fecundity of its host insect.
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Affiliation(s)
- Songdou Zhang
- Department of Entomology, China Agricultural UniversityBeijingChina
| | - Shiheng An
- Department of Entomology, Henan Agricultural UniversityZhengzhouChina
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Li R, Wang X, Hu Y, Huang G. Analysis of huanglongbing-associated RNA-seq data reveals disturbances in biological processes within Citrus spp. triggered by Candidatus Liberibacter asiaticus infection. Front Plant Sci 2024; 15:1388163. [PMID: 38660443 PMCID: PMC11039969 DOI: 10.3389/fpls.2024.1388163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 03/27/2024] [Indexed: 04/26/2024]
Abstract
Introduction Huanglongbing (HLB), a disease that's ubiquitous worldwide, wreaks havoc on the citrus industry. The primary culprit of HLB is the gram-negative bacterium Candidatus Liberibacter asiaticus (CLas) that infects the phloem, but its damaging mechanism is yet to be fully understood. Methods and results In this study, a multitude of tools including weighted correlation network analysis (WGCNA), protein-protein interaction (PPI) network analysis and gene expression profiling are employed to unravel the intricacies of its pathogenesis. The investigation pinpoints various central genes, such as the ethylene-responsive transcription factor 9 (ERF9) and thioredoxin reductase 1 (TrxR1), that are associated with CLas invasion and resultant disturbances in numerous biological operations. Additionally, the study uncovers a range of responses through the detection of differential expressed genes (DEGs) across different experiments. The discovery of core DEGs leads to the identification of pivotal genes such as the sieve element occlusion (SEO) and the wall-associated receptor kinase-like 15 (WAKL15). PPI network analysis highlights potential vital proteins, while GO and KEGG pathway enrichment analysis illustrate a significant impact on multiple defensive and metabolic pathways. Gene set enrichment analysis (GSEA) indicates significant alterations in biological processes such as leaf senescence and response to biotic stimuli. Discussion This all-encompassing approach extends valuable understanding into the pathogenesis of CLas, potentially aiding future research and therapeutic strategies for HLB.
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Affiliation(s)
- Ruimin Li
- College of Life Sciences, Gannan Normal University, Ganzhou, China
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
| | - Xinyou Wang
- College of Life Sciences, Gannan Normal University, Ganzhou, China
| | - Yanan Hu
- College of Life Sciences, Gannan Normal University, Ganzhou, China
| | - Guiyan Huang
- College of Life Sciences, Gannan Normal University, Ganzhou, China
- China-USA Citrus Huanglongbing Joint Laboratory, National Navel Orange Engineering Research Center, Gannan Normal University, Ganzhou, China
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Zhao ST, Ran XT, Huang YY, Sang W, Derrick BE, Qiu BL. Transcriptomic response of citrus psyllid salivary glands to the infection of citrus Huanglongbing pathogen. Bull Entomol Res 2024:1-20. [PMID: 38444234 DOI: 10.1017/s0007485324000038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the key vector insect transmitting the Candidatus Liberibacter asiaticus (CLas) bacterium that causes the devastating citrus greening disease (Huanglongbing, HLB) worldwide. The D. citri salivary glands (SG) exhibit an important barrier against the transmission of HLB pathogen. However, knowledge on the molecular mechanism of SG defence against CLas infection is still limited. In the present study, we compared the SG transcriptomic response of CLas-free and CLas-infected D. citri using an illumine paired-end RNA sequencing. In total of 861 differentially expressed genes (DEGs) in the SG upon CLas infection, including 202 upregulated DEGs and 659 downregulated DEGs were identified. Functional annotation analysis showed that most of the DEGs were associated with cellular processes, metabolic processes, and the immune response. Gene ontology and Kyoto Encyclopaedia of Genes and Genomes enrichment analyses revealed that these DEGs were enriched in pathways involving carbohydrate metabolism, amino acid metabolism, the immune system, the digestive system, the lysosome, and endocytosis. A total of 16 DEGs were randomly selected to further validate the accuracy of RNA-Seq dataset by reverse-transcription quantitative polymerase chain reaction. This study provides substantial transcriptomic information regarding the SG of D. citri in response to CLas infection, which may shed light on the molecular interaction between D. citri and CLas, and provides new ideas for the prevention and control of citrus psyllid.
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Affiliation(s)
- San-Tao Zhao
- Engineering Research Centre of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Engineering Research Center of Biotechnology for Active Substances, Ministry of Education, Chongqing Normal University, Chongqing 401331, China
| | - Xiao-Tong Ran
- Engineering Research Centre of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Engineering Research Center of Biotechnology for Active Substances, Ministry of Education, Chongqing Normal University, Chongqing 401331, China
| | - Yu-Yang Huang
- Engineering Research Centre of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Wen Sang
- Engineering Research Centre of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | | | - Bao-Li Qiu
- Engineering Research Centre of Biological Control, Ministry of Education, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Engineering Research Center of Biotechnology for Active Substances, Ministry of Education, Chongqing Normal University, Chongqing 401331, China
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Liu L, Chen J, Jiang J, Liang J, Song Y, Chen Q, Yan F, Bai Z, Song Z, Liu J. Detection of Candidatus Liberibacter asiaticus and five viruses in individual Asian citrus psyllid in China. Front Plant Sci 2024; 15:1357163. [PMID: 38379950 PMCID: PMC10877018 DOI: 10.3389/fpls.2024.1357163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 01/18/2024] [Indexed: 02/22/2024]
Abstract
Introduction Asian citrus psyllid (ACP, Diaphorina citri) is an important transmission vector of "Candidatus Liberibacter asiaticus" (CLas), the causal agent of Huanglongbing (HLB), the most destructive citrus disease in the world. As there are currently no HLB-resistant rootstocks or varieties, the control of ACP is an important way to prevent HLB. Some viruses of insect vectors can be used as genetically engineered materials to control insect vectors. Methods To gain knowledge on viruses in ACP in China, the prevalence of five RNA and DNA viruses was successfully determined by optimizing reverse transcription polymerase chain reaction (RT-PCR) in individual adult ACPs. The five ACP-associated viruses were identified as follows: diaphorina citri bunyavirus 2, which was newly identified by high-throughput sequencing in our lab, diaphorina citri reovirus (DcRV), diaphorina citri picorna-like virus (DcPLV), diaphorina citri bunyavirus (DcBV), and diaphorina citri densovirus-like virus (DcDV). Results DcPLV was the most prevalent and widespread ACP-associated virus, followed by DcBV, and it was detected in more than 50% of all samples tested. DcPLV was also demonstrated to propagate vertically and found more in salivary glands among different tissues. Approximately 60% of all adult insect samples were co-infected with more than one insect pathogen, including the five ACP-associated viruses and CLas. Discussion This is the first time these viruses, including the newly identified ACP-associated virus, have been detected in individual adult ACPs from natural populations in China's five major citrus-producing provinces. These results provide valuable information about the prevalence of ACP-associated viruses in China, some of which have the potential to be used as biocontrol agents. In addition, analysis of the change in prevalence of pathogens in a single insect vector is the basis for understanding the interactions between CLas, ACP, and insect viruses.
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Affiliation(s)
- Luqin Liu
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Jing Chen
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Junyao Jiang
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Jiamei Liang
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Yaqin Song
- Guangxi Academy of Specialty Crops, Guangxi Citrus Breeding and Cultivation Research Center of Engineering Technology, Guangxi, China
| | - Qi Chen
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Fuling Yan
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Ziqin Bai
- Fruit Research Institute, Guizhou Provincial Academy of Agricultural Sciences, Guizhou, China
| | - Zhen Song
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
| | - Jinxiang Liu
- Citrus Research Institute, Southwest University/National Citrus Engineering Research Center, Chongqing, China
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Zuo S, Xu L, Zhang H, Jiang M, Wu S, Zhang LH, Zhou X, Wang J. FlgI Is a Sec-Dependent Effector of Candidatus Liberibacter asiaticus That Can Be Blocked by Small Molecules Identified Using a Yeast Screen. Plants (Basel) 2024; 13:318. [PMID: 38276775 PMCID: PMC10819201 DOI: 10.3390/plants13020318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/11/2024] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
Huanglongbing (HLB) is one of the most devastating diseases of citrus worldwide. The phloem-restricted bacterium Candidatus Liberibacter asiaticus (CLas) is considered to be the main pathogen responsible for HLB. There is currently no effective practical strategy for the control of HLB. Our understanding of how pathogens cause HLB is limited because CLas has not been artificially cultured. In this study, 15 potential virulence factors were predicted from the proteome of CLas through DeepVF and PHI-base searches. One among them, FlgI, was found to inhibit yeast growth when expressed in Saccharomyces cerevisiae. The expression of the signal peptide of FlgI fused with PhoA in Escherichia coli resulted in the discovery that FlgI was a novel Sec-dependent secretory protein. We further found that the carboxyl-terminal HA-tagged FlgI was secreted via outer membrane vesicles in Sinorhizobium meliloti. Fluoresence localization of transient expression FlgI-GFP in Nicotiana benthamiana revealed that FlgI is mainly localized in the cytoplasm, cell periphery, and nuclear periphery of tobacco cells. In addition, our experimental results suggest that FlgI has a strong ability to induce callose deposition and cell necrosis in N. benthamiana. Finally, by screening a large library of compounds in a high-throughput format, we found that cyclosporin A restored the growth of FlgI-expressing yeast. These results confirm that FlgI is a novel Sec-dependent effector, enriching our understanding of CLas pathogenicity and helping to develop new and more effective strategies to manage HLB.
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Affiliation(s)
| | | | | | | | | | | | - Xiaofan Zhou
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China; (S.Z.); (L.X.); (H.Z.); (M.J.); (S.W.); (L.-H.Z.)
| | - Junxia Wang
- Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou 510642, China; (S.Z.); (L.X.); (H.Z.); (M.J.); (S.W.); (L.-H.Z.)
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Du P, Hu J, Du M, Gao X, Yang W, Zhang C, Zou X, Wang X, Li W. Interaction of a bacterial non-classically secreted RNase HⅠ with a citrus B-Box zinc finger protein delays flowering in Arabidopsis thaliana and suppresses the expression of FLOWERING LOCUS T. Microbiol Res 2024; 278:127541. [PMID: 37972521 DOI: 10.1016/j.micres.2023.127541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/21/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
Ribonuclease HI (RNase HI) is well conserved across prokaryotes and eukaryotes, and has long been known to localize in the nucleic acid-containing cellular compartments for acting as an R-loop eraser but has never been determined to be a secreted protein. "Candidatus Liberibacter asiaticus" (CLas) is a fastidious α-proteobacterium that causes Huanglongbing (HLB), a devastating citrus disease often associated with flowering out of season. In this study, using the SecretomeP program coupled with an Escherichia coli-based alkaline phosphatase assay, we demonstrated that the CLas RNase HI (LasRNHⅠ) was a non-classically secreted protein. Further experiments identified that LasRNHⅠ could interact with a citrus B-box zinc finger protein CsBBX28 in the plant nucleolus. The in vitro assays indicated that CsBBX28 dramatically enhanced the R-loop-degrading activity of LasRNHⅠ. Remarkably, co-expression of CsBBX28 and LasRNHⅠ in Arabidopsis thaliana led to a much later flowering time than that of wild-type Arabidopsis, as well as that of the transgenic A. thaliana expressing only CsBBX28 or LasRNHⅠ, and lastingly and significantly repressed transcription of FLOWERING LOCUS T (FT), a floral pathway integrator. Similarly, ectopic expression of LasRNHⅠ in citrus greatly reduced the transcription level of FT. The data together disclosed the extracellular secretion of LasRNHⅠ, and that LasRNHⅠ physically interacted with CsBBX28 and served as a flowering repressor through suppressing the FT expression, suggesting a novel role of RNase HI in the bacteria interacting with the host plants.
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Affiliation(s)
- Peixiu Du
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206, PR China; Innovative Institute of Chinese Medicine and Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Junxia Hu
- Department of Plant Protection, Beijing University of Agriculture, Beijing 102206, PR China
| | - Meixia Du
- Citrus Research Institute, Southwest University, Chongqing 400716, PR China
| | - Xiaoyu Gao
- Department of Plant Protection, Beijing University of Agriculture, Beijing 102206, PR China
| | - Wendi Yang
- Department of Plant Protection, Beijing University of Agriculture, Beijing 102206, PR China
| | - Chao Zhang
- College of Life Science, Hebei Agricultural University, Baoding 071001, PR China
| | - Xiuping Zou
- Citrus Research Institute, Southwest University, Chongqing 400716, PR China
| | - Xuefeng Wang
- Citrus Research Institute, Southwest University, Chongqing 400716, PR China
| | - Weimin Li
- Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206, PR China; Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; Department of Plant Protection, Beijing University of Agriculture, Beijing 102206, PR China.
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Zheng Y, Li Y, Xu P, Liu C, Chen J, Deng X, Zheng Z. Genome sequence resource for " Candidatus Liberibacter asiaticus" strain GDCZ from a historical HLB endemic region in China. BMC Genom Data 2023; 24:63. [PMID: 37923990 PMCID: PMC10625202 DOI: 10.1186/s12863-023-01160-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/19/2023] [Indexed: 11/06/2023] Open
Abstract
OBJECTIVES "Candidatus Liberibacter asiaticus" (CLas) is an un-culturable α-proteobacterium that caused citrus Huanglongbing (HLB), a destructive disease threatening citrus production worldwide. In China, the presence of HLB was first reported in Chaoshan region of Guangdong province, China around a century ago. Thus, whole genome information of CLas strains from Chaoshan area become the most important resource to understand the population diversity and evaluation of CLas in China. DATA DESCRIPTION CLas strain GDCZ was originally from Chaozhou city (Chaoshan area) and sequenced using PacBio Sequel long-read sequencing and Illumina short-read sequencing. The genome of strain GDCZ comprised of 1,230,507 bp with an average G + C content of 36.4%, along with a circular CLasMV1 phage: CLasMV1_GDCZ (8,869 bp). The CLas strain GDCZ contained a Type 2 prophage (37,452 bp) and encoded a total of 1,057 open reading frames and 53 RNA genes. The whole genome sequence of CLas strain GDCZ from the historical HLB endemic region in China will serve as a useful resource for further analyses of CLas evolution and HLB epidemiology in China and world.
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Affiliation(s)
- Yongqin Zheng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, Guangdong, China
| | - Yun Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, Guangdong, China
| | - Pengbin Xu
- Chaozhou Fruit Research Institute, Chaozhou, Guangdong, China
| | - Chaoji Liu
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, Guangdong, China
- Chaozhou Fruit Research Institute, Chaozhou, Guangdong, China
| | - Jianchi Chen
- San Joaquin Valley Agricultural Sciences Center, Agricultural Research Service, United States Department of Agriculture, Parlier, CA, USA
| | - Xiaoling Deng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China.
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, Guangdong, China.
| | - Zheng Zheng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China.
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, Guangdong, China.
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Lonare S, Sharma M, Dalal V, Gubyad M, Kumar P, Nath Gupta D, Pareek A, Tomar S, Kumar Ghosh D, Kumar P, Kumar Sharma A. Identification and evaluation of potential inhibitor molecules against TcyA from Candidatus Liberibacter asiaticus. J Struct Biol 2023; 215:107992. [PMID: 37394197 DOI: 10.1016/j.jsb.2023.107992] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/19/2023] [Accepted: 06/29/2023] [Indexed: 07/04/2023]
Abstract
Of the two putative amino acid binding periplasmic receptors of ABC transporter family in Candidatus Liberibacter asiaticus (CLas), cystine binding receptor (CLasTcyA) has been shown to mainly express in phloem of citrus plant and is a target for inhibitor development. The crystal structure of CLasTcyA in complex with substrates has been reported earlier. The present work reports the identification and evaluation of potential candidates for their inhibitory potential against CLasTcyA. Among many compounds, selected through virtual screening, and MD simulation, pimozide, clidinium, sulfasalazine and folic acid showed significantly higher affinities and stability in complex with CLasTcyA. The SPR studies with CLasTcyA revealed significantly higher binding affinities for pimozide and clidinium (Kd, 2.73 nM and 70 nM, respectively) as compared to cystine (Kd, 1.26 µM). The higher binding affinities could be attributed to significantly increased number of interactions in the binding pocket as evident from the crystal structures of CLasTcyA in complex with pimozide and clidinium as compared to cystine. The CLasTcyA possess relatively large binding pocket where bulkier inhibitors fit quite well. In planta studies, carried out to assess the effect of inhibitors on HLB infected Mosambi plants, showed significant reduction in CLas titre in plants treated with inhibitors as compared to control plants. The results showed that pimozide exhibited higher efficiency as compared to clidinium in reducing CLas titre in treated plants. Our results showed that the inhibitor development against critical proteins like CLasTcyA can be an important strategy in management of HLB.
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Affiliation(s)
- Sapna Lonare
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Monica Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Vikram Dalal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Mrugendra Gubyad
- Plant Virology Laboratory, ICAR Central Citrus Research Institute, Nagpur, India
| | - Pranav Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Deena Nath Gupta
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Akshay Pareek
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Shailly Tomar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Dilip Kumar Ghosh
- Plant Virology Laboratory, ICAR Central Citrus Research Institute, Nagpur, India
| | - Pravindra Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee-247667, India.
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Danda T, Park JW, Timmons KL, Sétamou M, Louzada ES, Kunta M. A Field Deployable Real-Time Loop-Mediated Isothermal Amplification Targeting Five Copy nrdB Gene for the Detection of ' Candidatus Liberibacter asiaticus' in Citrus. Plant Pathol J 2023; 39:309-318. [PMID: 37550978 PMCID: PMC10412965 DOI: 10.5423/ppj.oa.02.2023.0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/24/2023] [Accepted: 06/09/2023] [Indexed: 08/09/2023]
Abstract
Huanglongbing (HLB) is one of the most destructive diseases in citrus, which imperils the sustainability of citriculture worldwide. The presumed causal agent of HLB, 'Candidatus Liberibacter asiaticus' (CLas) is a non-culturable phloem-limited α-proteobacterium transmitted by Asian citrus psyllids (ACP, Diaphorina citri Kuwayama). A widely adopted method for HLB diagnosis is based on quantitative real-time polymerase chain reaction (qPCR). Although HLB diagnostic qPCR provides high sensitivity and good reproducibility, it is limited by time-consuming DNA preparation from plant tissue or ACP and the requirement of proper lab instruments including a thermal cycler to conduct qPCR. In an attempt to develop a quick assay that can be deployed in the field for CLas detection, we developed a real-time loop-mediated isothermal amplification (rt-LAMP) assay by targeting the CLas five copy nrdB gene. The rt-LAMP assay using various plant sample types and psyllids successfully detected the nrdB target as low as ~2.6 Log10 copies. Although the rt-LAMP assay was less sensitive than laboratory-based qPCR (detection limit ~10 copies), the data obtained with citrus leaf and bark and ACP showed that the rt-LAMP assay has >96% CLas detection rate, compared to that of laboratory-based qPCR. However, the CLas detection rate in fibrous roots was significantly decreased compared to qPCR due to low CLas titer in some root DNA sample. We also demonstrated that the rt-LAMP assay can be used with a crude leaf DNA extract which is fully deployable in the field for quick and reliable HLB screening.
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Affiliation(s)
- Tirumalareddy Danda
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
| | - Jong-Won Park
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
| | - Kimberly L. Timmons
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
| | - Mamoudou Sétamou
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
| | - Eliezer S. Louzada
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
| | - Madhurababu Kunta
- Texas A&M University-Kingsville Citrus Center, 312 N. International Blvd., Weslaco, TX 78599,
USA
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11
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Gao C, Li C, Li Z, Liu Y, Li J, Guo J, Mao J, Fang F, Wang C, Deng X, Zheng Z. Comparative transcriptome profiling of susceptible and tolerant citrus species at early and late stage of infection by " Candidatus Liberibacter asiaticus". Front Plant Sci 2023; 14:1191029. [PMID: 37389294 PMCID: PMC10301834 DOI: 10.3389/fpls.2023.1191029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/29/2023] [Indexed: 07/01/2023]
Abstract
Citrus Huanglongbing (HLB), caused by "Candidatus Liberibacter asiaticus" (CLas), is the most destructive disease threatening global citrus industry. Most commercial cultivars were susceptible to HLB, although some showed tolerant to HLB phenotypically. Identifying tolerant citrus genotypes and understanding the mechanism correlated with tolerance to HLB is essential for breeding citrus variety tolerance/resistance to HLB. In this study, the graft assay with CLas-infected bud were performed in four citrus genotypes, including Citrus reticulata Blanco, C. sinensis, C. limon, and C. maxima. HLB tolerance was observed in C. limon and C. maxima, while C. Blanco and C. sinensis were susceptible to HLB. The time-course transcriptomic analysis revealed a significant variation in differentially expressed genes (DEGs) related to HLB between susceptible and tolerant cultivar group at early and late infection stage. Functional analysis of DEGs indicated that the activation of genes involved in SA-mediated defense response, PTI, cell wall associated immunity, endochitinase, phenylpropanoid and alpha-linolenic/linoleic lipid metabolism played an important in the tolerance of C. limon and C. maxima to HLB at early infection stage. In addition, the overactive plant defense combined with the stronger antibacterial activity (antibacterial secondary and lipid metabolism) and the suppression of pectinesterase were contributed to the long-term tolerance to HLB in C. limon and C. maxima at late infection stage. Particularly, the activation of ROS scavenging genes (catalases and ascorbate peroxidases) could help to reduce HLB symptoms in tolerant cultivars. In contrast, the overexpression of genes involved in oxidative burst and ethylene metabolism, as well as the late inducing of defense related genes could lead to the early HLB symptom development in susceptible cultivars at early infection stage. The weak defense response and antibacterial secondary metabolism, and the induce of pectinesterase were responsible for sensitivity to HLB in C. reticulata Blanco and C. sinensis at late infection stage. This study provided new insights into the tolerance/sensitivity mechanism against HLB and valuable guidance for breeding of HLB-tolerant/resistant cultivars.
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Affiliation(s)
- Chenying Gao
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Cuixiao Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Ziyi Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Yaoxin Liu
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
- Horticulture Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, Guangxi, China
| | - Jiaming Li
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Jun Guo
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
- Institute of Tropical and Subtropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan, Yunnan, China
| | - Jiana Mao
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Fang Fang
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Cheng Wang
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Xiaoling Deng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Zheng Zheng
- National Key Laboratory of Green Pesticide, South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
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12
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Dominguez J, Jayachandran K, Stover E, Krystel J, Shetty KG. Endophytes and Plant Extracts as Potential Antimicrobial Agents against Candidatus Liberibacter Asiaticus, Causal Agent of Huanglongbing. Microorganisms 2023; 11:1529. [PMID: 37375030 DOI: 10.3390/microorganisms11061529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/02/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
Huanglongbing (HLB), also known as citrus greening, is an insidious disease in citrus and has become a threat to the sustainability of the citrus industry worldwide. In the U.S., Candidatus Liberibacter asiaticus (CLas) is the pathogen that is associated with HLB, an unculturable, phloem-limited bacteria, vectored by the Asian Citrus Psyllid (ACP, Diaphorina citri). There is no known cure nor treatment to effectively control HLB, and current control methods are primarily based on the use of insecticides and antibiotics, where effectiveness is limited and may have negative impacts on beneficial and non-target organisms. Thus, there is an urgent need for the development of effective and sustainable treatment options to reduce or eliminate CLas from infected trees. In the present study, we screened citrus-derived endophytes, their cell-free culture supernatants (CFCS), and crude plant extracts for antimicrobial activity against two culturable surrogates of CLas, Sinorhizobium meliloti and Liberibacter crescens. Candidates considered high-potential antimicrobial agents were assessed directly against CLas in vitro, using a propidium monoazide-based assay. As compared to the negative controls, statistically significant reductions of viable CLas cells were observed for each of the five bacterial CFCS. Subsequent 16S rRNA gene sequencing revealed that each of the five bacterial isolates were most closely related to Bacillus amyloliquefaciens, a species dominating the market of biological control products. As such, the aboveground endosphere of asymptomatic survivor citrus trees, grown in an organic orchard, were found to host bacterial endophytes capable of effectively disrupting CLas cell membranes. These results concur with the theory that native members of the citrus microbiome play a role in the development of HLB. Here, we identify five strains of Bacillus amyloliquefaciens demonstrating notable potential to be used as sources of novel antimicrobials for the sustainable management of HLB.
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Affiliation(s)
- Jessica Dominguez
- Department of Earth and Environment, Florida International University, Miami, FL 33199, USA
| | | | - Ed Stover
- United States Department of Agriculture/Agricultural Research Service, Ft. Pierce, FL 34945, USA
| | - Joseph Krystel
- United States Department of Agriculture/Agricultural Research Service, Ft. Pierce, FL 34945, USA
| | - Kateel G Shetty
- Department of Earth and Environment, Florida International University, Miami, FL 33199, USA
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13
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Wei W, Ait Barka E, Eichmeier A. Editorial: Recent advances in crop diseases associated with plant vascular-colonizing bacteria. Front Plant Sci 2023; 14:1171973. [PMID: 37063232 PMCID: PMC10100497 DOI: 10.3389/fpls.2023.1171973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 03/23/2023] [Indexed: 06/19/2023]
Affiliation(s)
- Wei Wei
- Beltsville Agricultural Research Center, Molecular Plant Pathology Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD, United States
| | - Essaid Ait Barka
- Unité de Recherche Résistance Induite et Bio-Protection des Plantes-EA 4707 – USC INRAe1488, Université de Reims Champagne-Ardenne, Reims, France
| | - Ales Eichmeier
- Mendeleum – Institute of Genetics, Mendel University in Brno, Brno, Czechia
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14
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Umair Raza M, Abasi F, Shahbaz M, Ehsan M, Seerat W, Akram A, Raja NI, Mashwani ZU, Hassan HU, Proćków J. Phytomediated Silver Nanoparticles (AgNPs) Embellish Antioxidant Defense System, Ameliorating HLB-Diseased 'Kinnow' Mandarin Plants. Molecules 2023; 28. [PMID: 36903290 DOI: 10.3390/molecules28052044] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 01/31/2023] [Accepted: 02/11/2023] [Indexed: 02/24/2023] Open
Abstract
Citrus production is harmed worldwide by yellow dragon disease, also known as Huanglongbing (HLB), or citrus greening. As a result, it has negative effects and a significant impact on the agro-industrial sector. There is still no viable biocompatible treatment for Huanglongbing, despite enormous efforts to combat this disease and decrease its detrimental effects on citrus production. Nowadays, green-synthesized nanoparticles are gaining attention for their use in controlling various crop diseases. This research is the first scientific approach to examine the potential of phylogenic silver nanoparticles (AgNPs) to restore the health of Huanglongbing-diseased 'Kinnow' mandarin plants in a biocompatible manner. AgNPs were synthesized using Moringa oleifera as a reducing, capping, and stabilizing agent and characterized using different characterization techniques, i.e., UV-visible spectroscopy with a maximum average peak at 418 nm, scanning electron microscopy (SEM) with a size of 74 nm, and energy-dispersive spectroscopy (EDX), which confirmed the presence of silver ions along with different elements, and Fourier transform infrared spectroscopy served to confirm different functional groups of elements. Exogenously, AgNPs at various concentrations, i.e., 25, 50, 75, and 100 mgL-1, were applied against Huanglongbing-diseased plants to evaluate the physiological, biochemical, and fruit parameters. The findings of the current study revealed that 75 mgL-1 AgNPs were most effective in boosting the plants' physiological profiles, i.e., chl a, chl b, total chl, carotenoid content, MSI, and RWC up to 92.87%, 93.36%, 66.72%, 80.95%, 59.61%, and 79.55%, respectively; biochemical parameters, i.e., 75 mgL-1 concentration decreased the proline content by up to 40.98%, and increased the SSC, SOD, POD, CAT, TPC, and TFC content by 74.75%, 72.86%, 93.76%, 76.41%, 73.98%, and 92.85%, respectively; and fruit parameters, i.e., 75 mgL-1 concentration increased the average fruit weight, peel diameter, peel weight, juice weight, rag weight, juice pH, total soluble solids, and total sugarby up to 90.78%, 8.65%, 68.06%, 84.74%, 74.66%, 52.58%, 72.94%, and 69.69%, respectively. These findings enable us to develop the AgNP formulation as a potential citrus Huanglongbing disease management method.
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15
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Ghosh D, Kokane S, Savita BK, Kumar P, Sharma AK, Ozcan A, Kokane A, Santra S. Huanglongbing Pandemic: Current Challenges and Emerging Management Strategies. Plants (Basel) 2022; 12:plants12010160. [PMID: 36616289 PMCID: PMC9824665 DOI: 10.3390/plants12010160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 05/09/2023]
Abstract
Huanglongbing (HLB, aka citrus greening), one of the most devastating diseases of citrus, has wreaked havoc on the global citrus industry in recent decades. The culprit behind such a gloomy scenario is the phloem-limited bacteria "Candidatus Liberibacter asiaticus" (CLas), which are transmitted via psyllid. To date, there are no effective long-termcommercialized control measures for HLB, making it increasingly difficult to prevent the disease spread. To combat HLB effectively, introduction of multipronged management strategies towards controlling CLas population within the phloem system is deemed necessary. This article presents a comprehensive review of up-to-date scientific information about HLB, including currently available management practices and unprecedented challenges associated with the disease control. Additionally, a triangular disease management approach has been introduced targeting pathogen, host, and vector. Pathogen-targeting approaches include (i) inhibition of important proteins of CLas, (ii) use of the most efficient antimicrobial or immunity-inducing compounds to suppress the growth of CLas, and (iii) use of tools to suppress or kill the CLas. Approaches for targeting the host include (i) improvement of the host immune system, (ii) effective use of transgenic variety to build the host's resistance against CLas, and (iii) induction of systemic acquired resistance. Strategies for targeting the vector include (i) chemical and biological control and (ii) eradication of HLB-affected trees. Finally, a hypothetical model for integrated disease management has been discussed to mitigate the HLB pandemic.
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Affiliation(s)
- Dilip Ghosh
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
- Correspondence: (D.G.); (A.K.S.); (S.S.)
| | - Sunil Kokane
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
| | - Brajesh Kumar Savita
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Pranav Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, India
- Correspondence: (D.G.); (A.K.S.); (S.S.)
| | - Ali Ozcan
- Vocational School of Technical Sciences, Karamanoglu Mehmetbey University, 70200 Karaman, Turkey
- Scientific and Technological Studies Application and Research Center, Karamanoglu Mehmetbey University, 70200 Karaman, Turkey
| | - Amol Kokane
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur 440033, India
| | - Swadeshmukul Santra
- Departments of Chemistry, Nano Science Technology Center, and Burnett School of Biomedical Sciences, University of Central Florida, Orlando, FL 32816, USA
- Correspondence: (D.G.); (A.K.S.); (S.S.)
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16
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Yu Q, Dai F, Russo R, Guha A, Pierre M, Zhuo X, Wang YZ, Vincent C, Gmitter FG. Phenotypic and Genetic Variation in Morphophysiological Traits in Huanglongbing-Affected Mandarin Hybrid Populations. Plants (Basel) 2022; 12:42. [PMID: 36616171 PMCID: PMC9824356 DOI: 10.3390/plants12010042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/13/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Huanglongbing (HLB) caused by 'Candidatus Liberibacter asiaticus' (CLas) is the most costly disease for the global citrus industry. Currently, no effective tools have been found to control HLB. Most commercial citrus varieties are susceptible to HLB, though some citrus hybrid cultivars have reduced sensitivity to the disease. Citrus breeding populations contain a large diversity of germplasm, with thousands of unique genotypes exhibiting a broad range of phenotypes. Understanding phenotypic variation and genetic inheritance in HLB-affected mandarin hybrid populations are crucial for breeding tolerant citrus varieties. In this study, we assessed 448 diverse mandarin hybrids coming from 30 crosses, and 45 additional accessions. For HLB tolerance, we measured HLB severity visual score and CLas titers by qPCR. We also measured seven morphophysiological traits indirectly related to HLB tolerance with leaf area index (LAI), leaf area (LA), leaf mass per area (LMA), photosystem II parameters (Fv/Fo, Fv/Fm), and photochemical performance index (PIabs). By estimating the genetic variation in five half-sib families, we estimated the heritability of phenotypic traits and found a significant genetic effect on HLB visual score and photosynthesis parameters, which indicates opportunities for the genetic improvement of HLB tolerance. In addition, although it is easy to identify infected trees based on HLB symptomatic leaves, visually phenotyping whole trees can be difficult and inconsistent due to the interpersonal subjectivity of characterization. We investigated their relationships and found that LAI was highly correlated with HLB score, with correlation coefficients of r = 0.70 and r = 0.77 for the whole population and five half-sib families, respectively. Photochemical parameters showed significant correlation with HLB severity and responded differentially with the side of the canopy. Our study suggests that LAI and photochemical parameters could be used as a rapid and cost-effective method to evaluate HLB tolerance and inheritance in citrus breeding programs.
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Affiliation(s)
- Qibin Yu
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Fanwei Dai
- Institute of Sericulture and Agricultural Products Processing, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, China
| | - Riccardo Russo
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Anirban Guha
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Myrtho Pierre
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Xiaokang Zhuo
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Yuanzhi Zimmy Wang
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Christopher Vincent
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
| | - Frederick G. Gmitter
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL 33850, USA
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17
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Gao F, Wu B, Zou C, Bao Y, Li D, Yao W, Powell CA, Zhang M. Genetic Diversity of " Candidatus Liberibacter asiaticus" Based on Four Hypervariable Genomic Regions in China. Microbiol Spectr 2022; 10:e0262222. [PMID: 36409071 PMCID: PMC9769890 DOI: 10.1128/spectrum.02622-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 10/17/2022] [Indexed: 11/23/2022] Open
Abstract
Huanglongbing (HLB; greening disease), caused by Candidatus Liberibacter asiaticus (CLas), is the most damaging citrus disease worldwide. The disease has spread throughout the citrus-producing regions of Guangxi, Guangdong, Fujian, and others in China. A total of 1,788 HLB-like symptomatic or asymptomatic samples were collected from the Guangxi and Fujian provinces of China to decipher the genetic diversity of CLas and its correlation with geographic region and host plant. The disease was the most severe in orange and the least in pomelo. CLas bacteria associated with the specific geographical and citrus variety infected more than 50% of the HLB-like symptomatic samples. We identified 6,286 minor variations by comparing 35 published CLas genomes and observed a highly heterogeneous variation distribution across the genome, including four highly diverse nonprophages and three prophage segments. Four hypervariable genomic regions (HGRs) were identified to determine the genetic diversity among the CLas isolates collected from Guangxi and Fujian, China. A phylogenetic tree constructed from four HGRs showed that 100 CLas strains could be separated into four distinct clades. Ten new strains with high variations of prophage regions were identified in the mandarin and tangerine grown in new plantation areas of Guangxi. Characterizing these HGR variations in the CLas bacteria may provide insight into their evolution and adaptation to host plants and insects. IMPORTANCE The hypervariable genomic regions derived from 35 published CLas genomes were used to decipher the genetic diversity of CLas strains and identify 10 new strains with high variations in prophage regions. Characterizing these variations in the CLas bacteria might provide insight into their evolution and adaptation to host plants and insects in China.
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Affiliation(s)
- Fanglan Gao
- State Key Laboratory for Conservation and Utilization of Sub-Tropical Bio-Agricultural Resources, Guangxi University, Guangxi, China
| | - Bo Wu
- School of Computing, Clemson University, Clemson, South Carolina, USA
| | - Chengwu Zou
- State Key Laboratory for Conservation and Utilization of Sub-Tropical Bio-Agricultural Resources, Guangxi University, Guangxi, China
| | - Yixue Bao
- State Key Laboratory for Conservation and Utilization of Sub-Tropical Bio-Agricultural Resources, Guangxi University, Guangxi, China
| | - Dean Li
- Fruit Experimental Station, Agricultural and Rural Department of Guangxi, Nanning, China
| | - Wei Yao
- State Key Laboratory for Conservation and Utilization of Sub-Tropical Bio-Agricultural Resources, Guangxi University, Guangxi, China
| | | | - Muqing Zhang
- State Key Laboratory for Conservation and Utilization of Sub-Tropical Bio-Agricultural Resources, Guangxi University, Guangxi, China
- IRREC, IFAS, University of Florida, Fort Pierce, Florida, USA
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18
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Hu Y, Meng Y, Yao L, Wang E, Tang T, Wang Y, Dai L, Zhao M, Zhang HE, Fan X, Luo L, Xiang W, Zhang Z. Citrus Huanglongbing correlated with incidence of Diaphorina citri carrying Candidatus Liberibacter asiaticus and citrus phyllosphere microbiome. Front Plant Sci 2022; 13:964193. [PMID: 36466264 PMCID: PMC9716883 DOI: 10.3389/fpls.2022.964193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/05/2022] [Indexed: 06/17/2023]
Abstract
In China, citrus Huanglongbing (HLB) disease is caused by the Candidatus Liberibacter asiaticus bacterium, which is carried by the Asian citrus psyllid Diaphorina citri Kuwayama. It was hypothesized that the epidemic of the HLB may related with the rate of bacterium presence in the insect vector and bacterium content in plant tissues, as well as the phyllosphere microbe communities changes. This study systematically analyzed the presence or absence of Ca. L. asiaticus in citrus tree leaves and in the insect vector D. citri over a 6-year period using real-time PCR. In addition, changes in the number of bacteria carried by D. citri over 12 months were quantified, as well as the relationship between the proportion of D. citri carrying Ca. L. asiaticus and the proportion of plants infected with Ca. L. asiaticus were analyzed. Results showed that the proportion of D. citri carrying bacteria was stable and relatively low from January to September. The bacteria in citrus leaves relatively low in spring and summer, then peaked in December. The proportion of D. citri carrying bacteria gradually declined from 2014 to 2019. The proportion of D. citri carrying Ca. L. asiaticus showed a significant positive correlation with the proportion of diseased citrus. The phyllosphere bacterial and fungal communities on the healthy citrus leaf were significantly different with the disease leaf in April and December. Pathogenic invasions change the citrus phyllosphere microbial community structure. It could be summarized that citrus Huanglongbing correlated with incidence of Diaphorina citri carrying Candidatus Liberibacter asiaticus and citrus phyllosphere microbiome.
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Affiliation(s)
- Yang Hu
- Department of Tree Breeding, Zhejiang Academy of Forestry, Hangzhou, China
| | - Youqing Meng
- Zhejiang Provincial General Station of Plant Protection, Quarantine and Pesticide Management, Hangzhou, China
| | - Liangjin Yao
- Department of Tree Breeding, Zhejiang Academy of Forestry, Hangzhou, China
| | - Enguo Wang
- Department of Plant Protection, Zhejiang Linhai Agricultural Technology Extension Center, Taizhou, China
| | - Tao Tang
- Hunan Plant Protection Institute, Hunan Academy of Agricultural Science, Changsha, China
| | - Yunsheng Wang
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Liangying Dai
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Mingping Zhao
- Plant Protection and Quarantine Station, Bureau of Agriculture and Rural Affairs of Jianghua Yao Autonomous County, Yongzhou, China
| | - Hong-en Zhang
- School of Mathematical, Nankai University, Tianjin, China
| | - Xiaoyan Fan
- Institute of Environmental Biotechnology, Graz University of Technology, Graz, Austria
| | - Luyun Luo
- School of Advanced Agriculture and Bioengineering, Yangtze Normal University, Chongqing, China
| | - Wei Xiang
- Hunan Crop Research Institute, Hunan Academy of Agricultural Science, Changsha, China
| | - Zhuo Zhang
- Hunan Plant Protection Institute, Hunan Academy of Agricultural Science, Changsha, China
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19
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Abstract
Although the phloem is a highly specialized tissue, certain pathogens, including phytoplasmas, spiroplasmas, and viruses, have evolved to access and live in this sequestered and protected environment, causing substantial economic harm. In particular, Candidatus Liberibacter spp. are devastating citrus in many parts of the world. Given that most phloem pathogens are vectored, they are not exposed to applied chemicals and are therefore difficult to control. Furthermore, pathogens use the phloem network to escape mounted defenses. Our review summarizes the current knowledge of phloem anatomy, physiology, and biochemistry relevant to phloem/pathogen interactions. We focus on aspects of anatomy specific to pathogen movement, including sieve plate structure and phloem-specific proteins. Phloem sampling techniques are discussed. Finally, pathogens that cause particular harm to the phloem of crop species are considered in detail.
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Affiliation(s)
- Jennifer D Lewis
- Plant Gene Expression Center, USDA-ARS, Albany, California, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, USA
| | - Michael Knoblauch
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Robert Turgeon
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, New York, USA;
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20
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Su C, Ding F, Wang W, Song Z, Ali Q, Ali M, Hong N, Wang G, Han H. Time-resolved fluorescent microsphere lateral flow biosensors for rapid detection of Candidatus Liberibacter asiaticus. Plant Biotechnol J 2022; 20:1235-1237. [PMID: 35445511 PMCID: PMC9241365 DOI: 10.1111/pbi.13828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/02/2022] [Accepted: 04/13/2022] [Indexed: 05/30/2023]
Affiliation(s)
- Cong Su
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan, China
| | - Fang Ding
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Wenjing Wang
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan, China
| | - Zhiyong Song
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan, China
| | - Qurban Ali
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Mubassir Ali
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ni Hong
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Guoping Wang
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Heyou Han
- State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan, China
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21
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Moreira RR, Machado FJ, Lanza FE, Trombin VG, Bassanezi RB, de Miranda MP, Barbosa JC, da Silva Junior GJ, Behlau F. Impact of diseases and pests on premature fruit drop in sweet orange orchards in São Paulo state citrus belt, Brazil. Pest Manag Sci 2022; 78:2643-2656. [PMID: 35355409 DOI: 10.1002/ps.6894] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/25/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Despite technical improvements in the citrus chain and leadership in orange production achieved in the past decades, premature fruit drop remains a major component of crop loss in São Paulo state citrus belt, the largest sweet orange production area in the world. The present study aimed to determine, during five consecutive seasons, the impact of the diseases and pests on premature fruit drop in the orange belt. RESULTS Fruit drop due to the main diseases and pests averaged approximately 11.0%, which corresponded to approximately 63% of the annual fruit drop. The average fruit drop rate due to fruit borer and fruit flies combined was 4.0%, Huanglongbing (HLB) 3.3%, black spot 2.6%, leprosis 1.0% and citrus canker 0.3%. The average amount of fruit drop (million 40.8 kg boxes) and value of crop losses (million US$ dollars), in five seasons, were 12.7 and 66.2 for fruit borer/fruit flies, 11.0 and 57.9 for HLB, 8.1 and 42.2 for black spot, 3.1 and 15.6 for leprosis, and 0.9 and 4.9 for citrus canker, respectively. CONCLUSION Fruit borer and fruit flies (combined), HLB, black spot, leprosis and citrus canker are, in this order, the main diseases and pests in the orange belt of São Paulo state. All of these causes significantly increased the overall fruit drop rate in the evaluated seasons. The results will contribute to the development of the Brazilian citrus industry, while showing to other citrus-growing regions the potential that diseases and pests have to jeopardize production. © 2022 Society of Chemical Industry.
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Affiliation(s)
| | - Franklin Jackson Machado
- Fundo de Defesa da Citricultura - Fundecitrus, Araraquara, Brazil
- Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, Brazil
| | | | | | | | | | - José Carlos Barbosa
- Departamento de Estatística, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista "Júlio de Mesquita Filho", Jaboticabal, Brazil
| | | | - Franklin Behlau
- Fundo de Defesa da Citricultura - Fundecitrus, Araraquara, Brazil
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22
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Du M, Wang S, Dong L, Qu R, Zheng L, He Y, Chen S, Zou X. Overexpression of a " Candidatus Liberibacter Asiaticus" Effector Gene CaLasSDE115 Contributes to Early Colonization in Citrus sinensis. Front Microbiol 2022; 12:797841. [PMID: 35265048 PMCID: PMC8899593 DOI: 10.3389/fmicb.2021.797841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/20/2021] [Indexed: 11/29/2022] Open
Abstract
Huanglongbing (HLB), caused by "Candidatus liberibacter asiaticus" (CaLas), is one of the most devastating diseases in citrus but its pathogenesis remains poorly understood. Here, we reported the role of the CaLasSDE115 (CLIBASIA_05115) effector, encoded by CaLas, during pathogen-host interactions. Bioinformatics analyses showed that CaLasSDE115 was 100% conserved in all reported CaLas strains but had sequence differences compared with orthologs from other "Candidatus liberibacter." Prediction of protein structures suggested that the crystal structure of CaLasSDE115 was very close to that of the invasion-related protein B (IalB), a virulence factor from Bartonella henselae. Alkaline phosphatase (PhoA) assay in E. coli further confirmed that CaLasSDE115 was a Sec-dependent secretory protein while subcellular localization analyses in tobacco showed that the mature protein of SDE115 (mSDE115), without its putative Sec-dependent signal peptide, was distributed in the cytoplasm and the nucleus. Expression levels of CaLasSDE115 in CaLas-infected Asian citrus psyllid (ACP) were much higher (∼45-fold) than those in CaLas-infected Wanjincheng oranges, with the expression in symptomatic leaves being significantly higher than that in asymptomatic ones. Additionally, the overexpression of mSDE115 favored CaLas proliferation during the early stages (2 months) of infection while promoting the development of symptoms. Hormone content and gene expression analysis of transgenic plants also suggested that overexpressing mSDE115 modulated the transcriptional regulation of genes involved in systemic acquired resistance (SAR) response. Overall, our data indicated that CaLasSDE115 effector contributed to the early colonization of citrus by the pathogen and worsened the occurrence of Huanglongbing symptoms, thereby providing a theoretical basis for further exploring the pathogenic mechanisms of Huanglongbing disease in citrus.
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Affiliation(s)
| | | | | | | | | | | | | | - Xiuping Zou
- National Citrus Engineering Research Center, Citrus Research Institute, Southwest University, Chongqing, China
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23
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Rashidi M, Lin CY, Britt K, Batuman O, Al Rwahnih M, Achor D, Levy A. Diaphorina citri flavi-like virus localization, transmission, and association with Candidatus Liberibacter asiaticus in its psyllid host. Virology 2021; 567:47-56. [PMID: 34998225 DOI: 10.1016/j.virol.2021.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 12/23/2021] [Accepted: 12/23/2021] [Indexed: 11/30/2022]
Abstract
Huanglongbing is caused by Candidatus Liberibacter asiaticus (CLas) and transmitted by Diaphorina citri. D. citri harbors various insect-specific viruses, including the Diaphorina citri flavi-like virus (DcFLV). The distribution and biological role of DcFLV in its host and the relationship with CLas are unknown. DcFLV was found in various organs of D. citri, including the midgut and salivary glands, where it co-localized with CLas. CLas-infected nymphs had the highest DcFLV titers compared to the infected adults and CLas-free adults and nymphs. DcFLV was vertically transmitted to offspring from female D. citri and was temporarily detected in Citrus macrophylla and grapefruit leaves from greenhouse and field. The incidences of DcFLV and CLas were positively correlated in field-collected D. citri samples, suggesting that DcFLV might be associated with CLas in the vector. These results provide new insights on the interactions between DcFLV, the D. citri, and CLas.
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Affiliation(s)
- Mahnaz Rashidi
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA; Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Chun-Yi Lin
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Kellee Britt
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA; Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, USA
| | - Ozgur Batuman
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA; Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, USA
| | - Maher Al Rwahnih
- Department of Plant Pathology, University of California-Davis, Davis, CA, USA
| | - Diann Achor
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA
| | - Amit Levy
- Department of Plant Pathology, University of Florida, Gainesville, FL, USA; Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA.
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24
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Dong ZH, Low W, K Srivastava A, Liu XD, Riaz M, Tan QL, Sun XC, Hu CX. Association between plant nutrients, the development of Huanglongbing and abnormal growth symptoms in navel orange. Plant Biol (Stuttg) 2021; 23:1167-1176. [PMID: 34490708 DOI: 10.1111/plb.13320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Huanglongbing (HLB) causes extensive damage in citrus orchards worldwide. Symptoms include blotchy mottle leaf (BML) and little leaf chlorosis (LLC), and nutrient deficiency usually occurs concurrently. However, the relationship between plant mineral content and infection with Candidatus Liberibacter asiaticus (CLas) is not clearly established. We sampled 7-month-old autumn shoots with three characteristic phenotypes, asymptomatic leaf (AL), BML and LLC, representing HLB disease progression, and further divided samples into CLas-infected and uninfected based on PCR analysis. HLB infection decreased transfer coefficients of Mg and K from leaf to phloem tissues through regulation of the transporter genes Cs3g03790.1 and PtrMGT5, increasing the content of leaf Mg and K. HLB infection also decreased leaf Zn, xylem Ca and phloem Ca and Zn content. Leaf Ca, Mg, Zn and B content decreased while leaf K content increased significantly as symptoms progressed from AL to LLC. The transport of P from leaf to phloem tissue, as evaluated by the transfer coefficient, was regulated by the transporter CsiPT2, resulting in irregular levels of leaf P. Our results provide insights into the nutrient dynamics in Citrus in response to CLas infection and the progression of HLB symptoms.
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Affiliation(s)
- Z-H Dong
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
- Microelement Research Center/Hubei Provincial Engineering Laboratory for New Fertilizers/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, China
| | - W Low
- Ganzhou Citrus Research Institute, Ganzhou, Jiangxi Province, China
| | - A K Srivastava
- Indian Council of Agricultural Research-Central Citrus Research Institute, Nagpur, Maharashtra, India
| | - X-D Liu
- Microelement Research Center/Hubei Provincial Engineering Laboratory for New Fertilizers/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, China
| | - M Riaz
- The State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Root Biology Center, South China Agricultural University, Guangzhou, China
| | - Q-L Tan
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
- Microelement Research Center/Hubei Provincial Engineering Laboratory for New Fertilizers/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, China
| | - X-C Sun
- Microelement Research Center/Hubei Provincial Engineering Laboratory for New Fertilizers/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, China
| | - C-X Hu
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, Hubei, China
- Microelement Research Center/Hubei Provincial Engineering Laboratory for New Fertilizers/Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei, China
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25
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Kwak Y, Sun P, Meduri VR, Percy DM, Mauck KE, Hansen AK. Uncovering Symbionts Across the Psyllid Tree of Life and the Discovery of a New Liberibacter Species, " Candidatus" Liberibacter capsica. Front Microbiol 2021; 12:739763. [PMID: 34659173 PMCID: PMC8511784 DOI: 10.3389/fmicb.2021.739763] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 09/10/2021] [Indexed: 11/30/2022] Open
Abstract
Sap-feeding insects in the order Hemiptera associate with obligate endosymbionts that are required for survival and facultative endosymbionts that can potentially modify resistance to stress, enemies, development, and reproduction. In the superfamily Psylloidea, the jumping plant lice (psyllids), less is known about the diversity and prevalence of their endosymbionts compared to other sap-feeding pests such as aphids (Aphididae). To address this knowledge gap, using 16S rRNA sequencing we identify symbionts across divergent psyllid host lineages from around the world. Taking advantage of a new comprehensive phylogenomic analyses of Psylloidea, we included psyllid samples from 44 species of 35 genera of five families, collected from 11 international locations for this study. Across psyllid lineages, a total of 91 OTUs were recovered, predominantly of the Enterobacteriaceae (68%). The diversity of endosymbionts harbored by each psyllid species was low with an average of approximately 3 OTUs. Two clades of endosymbionts (clade 1 and 2), belonging to Enterobacteriaceae, were identified that appear to be long term endosymbionts of the psyllid families Triozidae and Psyllidae, respectively. We also conducted high throughput metagenomic sequencing on three Ca. Liberibacter infected psyllid species (Russelliana capsici, Trichochermes walkeri, and Macrohomotoma gladiata), initially identified from 16S rRNA sequencing, to obtain more genomic information on these putative Liberibacter plant pathogens. The phylogenomic analyses from these data identified a new Ca. Liberibacter species, Candidatus Liberibacter capsica, that is a potential pathogen of solanaceous crops. This new species shares a distant ancestor with Ca. L. americanus, which occurs in the same range as R. capsici in South America. We also detected the first association between a psyllid specializing on woody hosts and the Liberibacter species Ca. L. psyllaurous, which is a globally distributed pathogen of herbaceous crop hosts in the Solanaceae. Finally, we detected a potential association between a psyllid pest of figs (M. gladiata) and a Ca. Liberibacter related to Ca. L. asiaticus, which causes severe disease in citrus. Our findings reveal a wider diversity of associations between facultative symbionts and psyllids than previously reported and suggest numerous avenues for future work to clarify novel associations of ecological, evolutionary, and pathogenic interest.
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Affiliation(s)
- Younghwan Kwak
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | - Penglin Sun
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | | | - Diana M Percy
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Kerry E Mauck
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | - Allison K Hansen
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
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26
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Asad S, He P, He P, Li Y, Wu Y, Ahmed A, Wang Y, Munir S, He Y. Interactions between Indigenous Endophyte Bacillus subtilis L1-21 and Nutrients inside Citrus in Reducing Huanglongbing Pathogen Candidatus Liberibacter Asiaticus. Pathogens 2021; 10:1304. [PMID: 34684254 DOI: 10.3390/pathogens10101304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 11/17/2022] Open
Abstract
Huanglongbing (HLB) pathogen Candidatus Liberibacter asiaticus (CLas) brings a great concern about the phloem nutrient transport in diseased plants. There is an urgent need to find the best management strategies to reduce the losses in the citrus industry worldwide. Endophytic bacteria are negatively affected by CLas pathogen, and these endophytes are associated with improved availability of nutrients and pathogen resistance. This study underpins the relationship between CLas pathogen, endophyte population and nutrients availability in citrus plants. The citrus plants were treated with Bacillus subtilis L1-21 and Hoagland solution to find out synergism efficacy to mitigate citrus HLB. We showed that citrus shoots in the presence of 50% Hoagland solution displayed maximum number of endophytes with 6.28 × 103 to 3.04 × 105 CFU/g. Among 50 candidate strains, B. subtilis L1-21 emerged as potential antagonist against surrogate strain Xanthomonas citri subsp. citri. The citrus half-leaf method identified that application of endophyte L1-21 with 50% Hoagland solution successfully reduces the CLas abundance. We point out that this combination results in a higher number of endophytes population with 2.52 × 104 to 9.11 × 106 CFU/g after 60 days, and reduces CLas pathogen abundance in asymptomatic HLB plants. In HLB symptomatic citrus plants, B. subtilis L1-21 potentially increases the endophyte population from 1.11 × 104 to 5.26 × 107 CFU/g in the presence of Hoagland solution, and pathogen abundance was reduced from 9.51 × 105 to 1.06 × 104 copies/g. Altogether, we suggested that the presence of endophyte L1-21 with Hoagland solution is more effective in HLB asymptomatic citrus plants, but a slight reduction of pathogen was observed in symptomatic plants. The findings revealed the role of indigenous citrus endophyte B. subtilis L1-21 along with other nutrients in the reduction of CLas pathogen abundance inside symptomatic and asymptomatic plants in citrus endophyte–nutrient–pathogen interplay.
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27
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Abstract
Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus, is currently the most destructive disease of citrus and threatens production in all affected areas. There is no cure. Benign Xylella fastidiosa strain EB92-1 provided good control of Pierce's disease of grapevine by inducing host resistance; therefore, we evaluated the strain for the biological control of HLB in citrus. Treatment was by injection into the trunk of the trees. Strain EB92-1 was shown to colonize citrus and provided control of HLB by reducing both the incidence of symptomatic trees and the percentage of trees with severe symptoms in three separate trials. All trees were positive by quantitative PCR (qPCR) for Candidatus Liberibacter asiaticus at the start of the trials, and treatment did not eliminate the bacterium. In a trial of asymptomatic mature trees, a single treatment with EB92-1 reduced the incidence of trees with symptoms through 18 months after treatment and reduced the incidence of trees with severe symptoms through 3 years. In mature trees that had 60% incidence of mild HLB symptoms at trial initiation, percentage of trees with symptoms and trees with severe symptoms continued to develop in both the untreated and in the EB92-1-treated trees for 12 months. However, retreatment at 9 and 20 months prevented the development of additional severe symptoms in the EB92-1-treated trees throughout the remainder of the 5-year trial. In 2-year-old trees, incidence of trees with HLB symptoms was higher in the untreated trees than in the treated trees throughout the 6 years of the trial, reaching 90% in the untreated versus 50% in the treated. After 6 years, severity of symptoms was much lower in the EB92-1-treated trees, only 3% of the treated trees had become unproductive compared with 18% of the untreated. In 2020, the reduction in HLB severity resulted in approximately twice as much yield in the treated trees as in these untreated 8-year-old trees. X. fastidiosa strain EB92-1 proved to be efficacious for the control of HLB symptoms in both mature trees and newly planted young trees, but trees may need to be retreated yearly for at least the first 2 to 3 years.
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Affiliation(s)
- D L Hopkins
- Mid-Florida Research and Education Center, University of Florida, Apopka, FL 32703
| | - K L Ager
- Mid-Florida Research and Education Center, University of Florida, Apopka, FL 32703
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28
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Wang F, Wu Y, Wu W, Huang Y, Zhu C, Zhang R, Chen J, Zeng J. Integrative analysis of metabolome and transcriptome profiles provides insight into the fruit pericarp pigmentation disorder caused by ' Candidatus Liberibacter asiaticus' infection. BMC Plant Biol 2021; 21:397. [PMID: 34433413 PMCID: PMC8385863 DOI: 10.1186/s12870-021-03167-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Mandarin 'Shatangju' is susceptible to Huanglongbing (HLB) and the HLB-infected fruits are small, off-flavor, and stay-green at the maturity period. To understand the relationship between pericarp color and HLB pathogen and the effect mechanism of HLB on fruit pericarp coloration, quantitative analyses of HLB bacterial pathogens and carotenoids and also the integrative analysis of metabolome and transcriptome profiles were performed in the mandarin 'Shatangju' variety with four different color fruits, whole green fruits (WGF), top-yellow and base-green fruits (TYBGF), whole light-yellow fruits (WLYF), and whole dark-yellow fruits (WDYF) that were infected with HLB. RESULTS the HLB bacterial population followed the order WGF > TYBGF > WLYF > WDYF. And there were significant differences between each group of samples. Regarding the accumulation of chlorophyll and carotenoid, the chlorophyll-a content in WGF was the highest and in WDYF was the lowest. The content of chlorophyll-b in WGF was significantly higher than that in other three pericarps. There were significant differences in the total content of carotenoid between each group. WGF and TYBGF pericarps were low in phytoene, γ-carotene, β-cryptoxanthin and apocarotenal, while other kinds of carotenoids were significantly higher than those in WDYF. And WLYF was only short of apocarotenal. We comprehensively compared the transcriptome and metabolite profiles of abnormal (WGF, TYBGF and WLYF) and normal (WDYF, control) pericarps. In total, 2,880, 2,782 and 1,053 differentially expressed genes (DEGs), including 121, 117 and 43 transcription factors were identified in the three comparisons, respectively. The qRT-PCR confirmed the expression levels of genes selected from transcriptome. Additionally, a total of 77 flavonoids and other phenylpropanoid-derived metabolites were identified in the three comparisons. Most (76.65 %) showed markedly lower abundances in the three comparisons. The phenylpropanoid biosynthesis pathway was the major enrichment pathway in the integrative analysis of metabolome and transcriptome profiles. CONCLUSIONS Synthesizing the above analytical results, this study indicated that different color pericarps were associated with the reduced levels of some carotenoids and phenylpropanoids derivatives products and the down-regulation of proteins in flavonoids, phenylpropanoids derivatives biosynthesis pathway and the photosynthesis-antenna proteins.
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Affiliation(s)
- Feiyan Wang
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
- College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Yunli Wu
- College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Wen Wu
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
| | - Yongjing Huang
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
| | - Congyi Zhu
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
| | - Ruimin Zhang
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
| | - Jiezhong Chen
- College of Horticulture, South China Agricultural University, 510642 Guangzhou, China
| | - Jiwu Zeng
- Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization & Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
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29
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Lu H, Fang X, Wu F, Ouyang G. Adaptability and ' Candidatus Liberibacter asiaticus' titres of Diaphorina citri adults on three weed species in China. Pest Manag Sci 2021; 77:3216-3223. [PMID: 33751790 DOI: 10.1002/ps.6360] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 02/19/2021] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Diaphorina citri is a vector of 'Candidatus Liberibacter asiaticus' (CLas), which is associated with citrus huanglongbing (HLB). In this study, the adaptability and CLas titres of D. citri adults on three weed species, namely, Ageratum conyzoides, Solanum nigrum and Praxelis clematidea, which are widely distributed in citrus orchards in China, were determined. RESULTS D. citri selected S. nigrum preferentially over the other weed species. The longest survival times of D. citri adults on A. conyzoides, S. nigrum and P. clematidea were 48, 41 and 11 days, respectively. On S. nigrum, the survivorship of females was significantly higher than that of males. The CLas titres of D. citri adults feeding on the three weeds for 1 week increased significantly during autumn but did not change significantly during spring. Conversely, the titres of adults on citrus increased significantly during spring but did not change significantly during autumn. CONCLUSION D. citri exhibited different adaptabilities to the three weed species, but the CLas titres of D. citri adults did not decrease on any of the weeds. These results suggested that the three weed species could help dispersing of D. citri and transmission of CLas while ideal host conditions were scarce or absent. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Huilin Lu
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Sciences, Guangzhou, China
| | - Xiaoduan Fang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Sciences, Guangzhou, China
| | - Fengnian Wu
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, China
| | - Gecheng Ouyang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangdong Academy of Sciences, Guangzhou, China
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30
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Nan J, Zhang S, Zhan P, Jiang L. Discovery of Novel GMPS Inhibitors of Candidatus Liberibacter Asiaticus by Structure Based Design and Enzyme Kinetic. Biology (Basel) 2021; 10:biology10070594. [PMID: 34203217 PMCID: PMC8301025 DOI: 10.3390/biology10070594] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 12/12/2022]
Abstract
Simple Summary The spread of citrus Huanglongbing caused significant damage to the world’s citrus industry. Thermotherapy and chemical agents were used to control this disease; however, the effectiveness of these treatments is frequently inconsistent. In addition, CLas cannot be cultured in vitro. Therefore, structure-based virtual screening is a novel method to find compounds that work against CLas. This study used CLas GMPS as a target for high-throughput screening and selected some compounds which have a higher binding affinity to test their inhibition of CLas GMPS. Finally, two molecules were identified as the lead compound to control citrus HLB. Abstract Citrus production is facing an unprecedented problem because of huanglongbing (HLB) disease. Presently, no effective HLB-easing method is available when citrus becomes infected. Guanosine 5′-monophosphate synthetase (GMPS) is a key protein in the de novo synthesis of guanine nucleotides. GMPS is used as an attractive target for developing agents that are effective against the patogen infection. In this research, homology modeling, structure-based virtual screening, and molecular docking were used to discover the new inhibitors against CLas GMPS. Enzyme assay showed that folic acid and AZD1152 showed high inhibition at micromole concentrations, with AZD1152 being the most potent molecule. The inhibition constant (Ki) value of folic acid and AZD1152 was 51.98 µM and 4.05 µM, respectively. These results suggested that folic acid and AZD1152 could be considered as promising candidates for the development of CLas agents.
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Affiliation(s)
- Jing Nan
- Ministry of Education Key Laboratory of Plant Biology, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Shaoran Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Ping Zhan
- Ministry of Education Key Laboratory of Plant Biology, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Ling Jiang
- Ministry of Education Key Laboratory of Plant Biology, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
- Correspondence:
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Fang F, Guo H, Zhao A, Li T, Liao H, Deng X, Xu M, Zheng Z. A Significantly High Abundance of " Candidatus Liberibacter asiaticus" in Citrus Fruit Pith: in planta Transcriptome and Anatomical Analyses. Front Microbiol 2021; 12:681251. [PMID: 34177866 PMCID: PMC8225937 DOI: 10.3389/fmicb.2021.681251] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/10/2021] [Indexed: 11/20/2022] Open
Abstract
Huanglongbing, a highly destructive disease of citrus, is associated with the non-culturable phloem-limited α-proteobacterium "Candidatus Liberibacter asiaticus" (CLas). The distribution patterns of CLas in infected plant are variable and not consistent, which make the CLas detection and characterization more challenging. Here, we performed a systemic analysis of CLas distribution in citrus branches and fruits of 14 cultivars. A significantly high concentration of CLas was detected in fruit pith (dorsal vascular bundle) of 14 citrus cultivars collected at fruit maturity season. A 2-year monitoring assay of CLas population in citrus branches of "Shatangju" mandarin (Citrus reticulata Blanco "Shatangju") revealed that CLas population already exhibited a high level even before the appearance of visual symptoms in the fruit rind. Quantitative analyses of CLas in serial 1.5-cm segments of fruit piths showed the CLas was unevenly distributed within fruit pith and tended to colonize in the middle or distal (stylar end) regions of pith. The use of CLas-abundant fruit pith for dual RNA-seq generated higher-resolution CLas transcriptome data compared with the leaf samples. CLas genes involved in transport system, flagellar assembly, lipopolysaccharide biosynthesis, virulence, stress response, and cell surface structure, as well as host genes involved in biosynthesis of antimicrobial-associated secondary metabolites, was up-regulated in leaf midribs compared with fruit pith. In addition, CLas infection caused the severe collapse in phloem and callose deposition in the plasmodesmata of fruit pith. The ability of fruit pith to support multiplication of CLas to high levels makes it an ideal host tissue for morphological studies and in planta transcriptome analyses of CLas-host interactions.
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Affiliation(s)
- Fang Fang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Hengyu Guo
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Anmin Zhao
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Tao Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Huihong Liao
- Horticulture Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, China
| | - Xiaoling Deng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Meirong Xu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
| | - Zheng Zheng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, China
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Wei X, Mira A, Yu Q, Gmitter FG. The Mechanism of Citrus Host Defense Response Repression at Early Stages of Infection by Feeding of Diaphorina citri Transmitting Candidatus Liberibacter asiaticus. Front Plant Sci 2021; 12:635153. [PMID: 34168662 PMCID: PMC8218908 DOI: 10.3389/fpls.2021.635153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 04/29/2021] [Indexed: 06/01/2023]
Abstract
Citrus Huanglongbing (HLB) is the most devastating disease of citrus, presumably caused by "Candidatus Liberibacter asiaticus" (CaLas). Although transcriptomic profiling of HLB-affected citrus plants has been studied extensively, the initial steps in pathogenesis have not been fully understood. In this study, RNA sequencing (RNA-seq) was used to compare very early transcriptional changes in the response of Valencia sweet orange (VAL) to CaLas after being fed by the vector, Diaphorina citri (Asian citrus psyllid, or ACP). The results suggest the existence of a delayed defense reaction against the infective vector in VAL, while the attack by the healthy vector prompted immediate and substantial transcriptomic changes that led to the rapid erection of active defenses. Moreover, in the presence of CaLas-infected psyllids, several downregulated differentially expressed genes (DEGs) were identified on the pathways, such as signaling, transcription factor, hormone, defense, and photosynthesis-related pathways at 1 day post-infestation (dpi). Surprisingly, a burst of DEGs (6,055) was detected at 5 dpi, including both upregulated and downregulated DEGs on the defense-related and secondary metabolic pathways, and severely downregulated DEGs on the photosynthesis-related pathways. Very interestingly, a significant number of those downregulated DEGs required ATP binding for the activation of phosphate as substrate; meanwhile, abundant highly upregulated DEGs were detected on the ATP biosynthetic and glycolytic pathways. These findings highlight the energy requirement of CaLas virulence processes. The emerging picture is that CaLas not only employs virulence strategies to subvert the host cell immunity, but the fast-replicating CaLas also actively rewires host cellular metabolic pathways to obtain the necessary energy and molecular building blocks to support virulence and the replication process. Taken together, the very early response of citrus to the CaLas, vectored by infective ACP, was evaluated for the first time, thus allowing the changes in gene expression relating to the primary mechanisms of susceptibility and host-pathogen interactions to be studied, and without the secondary effects caused by the development of complex whole plant symptoms.
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Affiliation(s)
- Xu Wei
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
- College of Horticulture and Landscape, Southwest University, Chongqing, China
| | - Amany Mira
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
- Department of Horticulture, Faculty of Agriculture, Tanta University, Tanta, Egypt
| | - Qibin Yu
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Fred G. Gmitter
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
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Pandey SS, Nogales da Costa Vasconcelos F, Wang N. Spatiotemporal Dynamics of ' Candidatus Liberibacter asiaticus' Colonization Inside Citrus Plant and Huanglongbing Disease Development. Phytopathology 2021; 111:921-928. [PMID: 33174821 DOI: 10.1094/phyto-09-20-0407-r] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
'Candidatus Liberibacter asiaticus' (CLas), the causal agent of citrus huanglongbing (HLB), colonizes inside the phloem and is naturally transmitted by the Asian citrus psyllid (ACP). Here, we investigated spatiotemporal CLas colonization in different tissues after ACP transmission. Of the nine plants successfully infected via ACP transmission, CLas was detected in the roots of all trees at 75 days postremoval of ACPs (DPR) but in the mature leaf of only one tree; this finding is consistent with the model that CLas moves passively from source to sink tissues. At 75 and 365 DPR, CLas was detected in 11.1 and 43.1% of mature leaves not fed on by ACPs during transmission, respectively, unveiling active movement to the source tissue. The difference in colonization timing of sink and source tissues indicates that CLas is capable of both passive and active movement, with passive movement being dominant. At 225 DPR, leaves fed on by ACPs during the young stage showed the highest ratio of HLB symptomatic leaves and the highest CLas titer, followed by leaves that emerged after ACP removal and mature leaves not fed on by ACPs. Importantly, our data showed that ACPs were unable to transmit CLas via feeding on mature leaves. It is estimated that it takes 3 years at most for CLas to infect the whole tree. Overall, spatiotemporal detection of CLas in different tissues after ACP transmission helps visualize the infection process of CLas in planta and subsequent HLB symptom development and provides evidence showing that young leaves should be the focus of HLB management.
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Affiliation(s)
- Sheo Shankar Pandey
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL 33850
| | | | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, Lake Alfred, FL 33850
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Zhang Z, Han Q, Mao X, Liu J, Wang W, Li D, Zhou F, Ke Y, Xu L, Hu L. Discovery of novel SecA inhibitors against " Candidatus Liberibacter asiaticus" through virtual screening and biological evaluation. Chem Biol Drug Des 2021; 98:395-404. [PMID: 33963664 DOI: 10.1111/cbdd.13859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/07/2021] [Accepted: 03/14/2021] [Indexed: 11/26/2022]
Abstract
"Candidatus Liberibacter asiaticus" (Ca. L. asiaticus) is the causal agent of Huanglongbing disease of citrus and current study focuses on the discovery of novel small-molecule inhibitors against SecA protein of Ca. L. asiaticus. In this study, homologous modeling was used to construct the three-dimensional structure of SecA. Then, molecular docking-based virtual screening and two rounds of in vitro bacteriostatic experiments were utilized to identify novel small-molecule inhibitors of SecA. Encouragingly, 93 compounds were obtained and two of them (P684-2850, P684-3808) showed strong antimicrobial activities against Liberibacter crescens BT-1 in bacteriostatic experiments. Finally, molecular dynamics simulations were employed to explore the binding modes of the receptor-ligand complexes. Results in MD simulations showed that compound P684-3808 was relatively stable during simulation, while compound P684-2850 left the binding pocket. Compound P684-3808 might be suitable as a lead compound for further development of antimicrobial compounds against SecA of Ca. L. asiaticus.
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Affiliation(s)
- Zhengfang Zhang
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Quan Han
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Xiongxing Mao
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Jinhua Liu
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Wei Wang
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Dong Li
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Feng Zhou
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
| | - Yang Ke
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Lei Xu
- Institute of Bioinformatics and Medical Engineering, Jiangsu University of Technology, Changzhou, China
| | - Liu Hu
- Zhejiang Yangshengtang Institute of Natural Medication Co., Ltd, Hangzhou, China
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Atta AA, Morgan KT, Kadyampakeni DM, Mahmoud KA. The Effect of Foliar and Ground-Applied Essential Nutrients on Huanglongbing-Affected Mature Citrus Trees. Plants (Basel) 2021; 10:925. [PMID: 34066426 PMCID: PMC8148103 DOI: 10.3390/plants10050925] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 11/23/2022]
Abstract
The fate of foliar and ground-applied essential nutrients is the least studied topic under citrus greening or Huanglongbing (HLB)-affected citrus, which is inherently suffering from severe root decline because of HLB-associated problems. The objective of this study was to evaluate if ground-applied coupled with foliar spray of essential nutrients can reverse the decline in tree growth and understand the fate of the nutrients in the soil-root-tree interfaces. The treatments were arranged in a split-split plot design in which nitrogen (N) was ground-applied in 20 splits biweekly and Mn, Zn, and B were foliar and /or ground-applied in three splits following the spring, summer, and late summer flush seasons. Soil nutrients in three depths (0-15, 15-30, and 30-45 cm), root, and leaf nutrient concentrations of the essential nutrients, leaf area index (LAI), and tree canopy volume (TCV) data were studied twice (spring and summer) for two years. A significantly higher soil NH4-N and NO3-N concentrations were detected in the topsoil depth than the two lower soil depths (15-30 and 30-45 cm) indicating lesser nutrient leaching as trees received moderate (224 kg ha-1) N rate. Except for soil zinc (Zn) concentration, all the nutrient concentrations were significantly higher in the topsoil (0-15 cm), compared with two lower soil depths indicating that Zn was intricate by changes in soil environmental conditions, root acquisition, and/or leaching to lower soil depth. Leaf N concentration significantly increased over time following seasonal environmental fluctuations, tree growth, and development. Thus, leaf N concentration remained above the optimum nutrient range implying lower N requirement under irrigation scheduling with SmartIrrigation, an App used to determine the daily irrigation duration to meet tree water requirement and split fertigation techniques. Root Manganese (Mn) and Zn concentrations were significantly higher in the root tissues of the treated than the control trees and translocated to the leaves accordingly. Meanwhile, a significantly higher LAI for trees budded on Swingle (Swc) rootstock however, larger TCV for trees budded on Volkameriana (Volk) rootstocks. The trees had significantly larger TCV when the trees received a moderate N rate during early study years and under foliar 9 kg ha-1 coupled with the ground 9 kg ha-1 Mn and Zn treatments during the late study years. Therefore, split ground application of 224 kg ha-1 of N, foliar applied 9 kg ha-1 coupled with ground-applied 9 kg ha-1 Mn and Zn were the suggested rates to sustain the essential leaf nutrient concentration within the optimum ranges and improve the deterioration of vegetative growth associated with HLB-induced problems of citrus trees.
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Affiliation(s)
- Alisheikh A. Atta
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (K.A.M.)
| | - Kelly T. Morgan
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (K.A.M.)
| | - Davie M. Kadyampakeni
- Citrus Research and Education Center, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA;
| | - Kamal A. Mahmoud
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (K.A.M.)
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Gupta DN, Dalal V, Savita BK, Dhankhar P, Ghosh DK, Kumar P, Sharma AK. In-silico screening and identification of potential inhibitors against 2Cys peroxiredoxin of Candidatus Liberibacter asiaticus. J Biomol Struct Dyn 2021; 40:8725-8739. [PMID: 33939584 DOI: 10.1080/07391102.2021.1916597] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Huanglongbing (HLB) is a worldwide citrus plant disease-related to non-culturable and fastidious α-proteobacteria Candidatus Liberibacter asiaticus (CLas). In CLas, Peroxiredoxin (Prx) plays a major role in the reduction of the level of reactive species such as reactive oxygen species (ROS), free radicals and peroxides, etc. Here, we have used structure-based drug designing approach was used to screen and identify the potent molecules against 2Cys Prx. The virtual screening of fragments library was performed against the three-dimensional validated model of Prx. To evaluate the binding affinity, the top four molecules (N-Boc-2-amino isobutyric acid (B2AI), BOC-L-Valine (BLV), 1-(boc-amino) cyclobutane carboxylic acid (1BAC), and N-Benzoyl-DL-alanine (BDLA)) were docked at the active site of Prx. The molecular docking results revealed that all the identified molecules had a higher binding affinity than Tert butyl hydroperoxide (TBHP), a substrate of Prx. Molecular dynamics analysis such as RMSD, Rg, SASA, hydrogen bonds, and PCA results indicated that Prx-inhibitor(s) complexes had lesser fluctuations and were more stable and compact than Prx-TBHP complex. MMPBSA results confirmed that the identified compounds could bind at the active site of Prx to form a lower energy Prx-inhibitor(s) complex than Prx-TBHP complex. The identified potent molecules may pave the path for the development of antimicrobial agents against CLA.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Deena Nath Gupta
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
| | - Vikram Dalal
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
| | - Brajesh Kumar Savita
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
| | - Poonam Dhankhar
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
| | - Dilip Kumar Ghosh
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur, Nagpur, India
| | - Pravindra Kumar
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
| | - Ashwani Kumar Sharma
- Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India
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Nehela Y, Killiny N. Diaphorina citri Genome Possesses a Complete Melatonin Biosynthesis Pathway Differentially Expressed under the Influence of the Phytopathogenic Bacterium, Candidatus Liberibacter asiaticus. Insects 2021; 12:317. [PMID: 33916117 PMCID: PMC8065666 DOI: 10.3390/insects12040317] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 03/29/2021] [Accepted: 03/29/2021] [Indexed: 11/17/2022]
Abstract
Melatonin is synthesized from the amino acid L-tryptophan via the shikimic acid pathway and ubiquitously distributed in both prokaryotes and eukaryotes. Although most of melatonin biosynthesis genes were characterized in several plants and animal species including the insect model, Drosophila melanogaster, none of these enzymes have been identified from the Asian citrus psyllid, Diaphorina citri. We used comprehensive in silico analysis and gene expression techniques to identify the melatonin biosynthesis-related genes of D. citri and to evaluate the expression patterns of these genes within the adults of D. citri with gradient infection rates (0, 28, 34, 50, 58, and 70%) of the phytopathogenic bacterium Candidatus Liberibacter asiaticus and after the treatment with exogenous melatonin. We showed that the D. citri genome possesses six putative melatonin biosynthesis-related genes including two putative tryptophan 5-hydroxylase (DcT5H-1 and DcT5H-2), a putative aromatic amino acid decarboxylase (DcAADC), two putative arylalkylamine N-acetyltransferase (DcAANAT-1 and DcAANAT-2), and putative N-acetylserotonin O-methyltransferase (DcASMT). The infection with Ca. L. asiaticus decreased the transcript levels of all predicted genes in the adults of D. citri. Moreover, melatonin supplementation induced their expression levels in both healthy and Ca. L. asiaticus-infected psyllids. These findings confirm the association of these genes with the melatonin biosynthesis pathway.
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Affiliation(s)
- Yasser Nehela
- Citrus Research and Education Center, Department of Plant Pathology, University of Florida, 700 Experiment Station Rd., Lake Alfred, FL 33850, USA;
- Department of Agricultural Botany, Faculty of Agriculture, Tanta University, Tanta 31511, Egypt
| | - Nabil Killiny
- Citrus Research and Education Center, Department of Plant Pathology, University of Florida, 700 Experiment Station Rd., Lake Alfred, FL 33850, USA;
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Liu K, He J, Guan Z, Zhong M, Pang R, Han Q. Transcriptomic and Metabolomic Analyses of Diaphorina citri Kuwayama Infected and Non-infected With Candidatus Liberibacter Asiaticus. Front Physiol 2021; 11:630037. [PMID: 33716757 PMCID: PMC7943627 DOI: 10.3389/fphys.2020.630037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/21/2020] [Indexed: 11/13/2022] Open
Abstract
The Asian citrus psyllid Diaphorina citri is the transmission vector of Huanglongbing (HLB), a devastating disease of citrus plants. The bacterium “Candidatus Liberibacter asiaticus” (CLas) associated with HLB is transmitted between host plants by D. citri in a circulative manner. Understanding the interaction between CLas and its insect vector is key for protecting citrus cultivation from HLB damage. Here, we used RNA sequencing and liquid chromatography-mass spectrometry (LC-MS) to analyze the transcriptome and metabolome of D. citri interacting with CLas. We identified 662 upregulated and 532 downregulated genes in CLas-infected insects. These genes were enriched in pathways involving carbohydrate metabolism, the insects’ immune system, and metabolism of cofactors and vitamins. We also detected 105 differential metabolites between CLas-infected and non-infected insects, including multiple nucleosides and lipid-related molecules. The integrated analysis revealed nine pathways—including those of the glycine, serine, threonine, and purine metabolism—affected by the differentially expressed genes from both groups. The network for these pathways was subsequently constructed. Our results thus provide insights regarding the cross-talk between the transcriptomic and metabolomic changes in D. citri in response to CLas infection, as well as information on the pathways and genes/metabolites related to the CLas–D. citri interaction.
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Affiliation(s)
- Kai Liu
- College of Agriculture and Biology, Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Jiawei He
- College of Agriculture and Biology, Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Ziying Guan
- College of Agriculture and Biology, Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Mingzhao Zhong
- College of Agriculture and Biology, Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Rui Pang
- Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou, China
| | - Qunxin Han
- College of Agriculture and Biology, Innovative Institute for Plant Health, Zhongkai University of Agriculture and Engineering, Guangzhou, China
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Franco JY, Thapa SP, Pang Z, Gurung FB, Liebrand TWH, Stevens DM, Ancona V, Wang N, Coaker G. Citrus Vascular Proteomics Highlights the Role of Peroxidases and Serine Proteases during Huanglongbing Disease Progression. Mol Cell Proteomics 2020; 19:1936-1952. [PMID: 32883801 PMCID: PMC7710146 DOI: 10.1074/mcp.ra120.002075] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 08/04/2020] [Indexed: 01/17/2023] Open
Abstract
Huanglongbing (HLB) is the most devastating and widespread citrus disease. All commercial citrus varieties are susceptible to the HLB-associated bacterium, Candidatus Liberibacter asiaticus (CLas), which resides in the phloem. The phloem is part of the plant vascular system and is involved in sugar transport. To investigate the plant response to CLas, we enriched for proteins surrounding the phloem in an HLB susceptible sweet orange variety, Washington navel (Citrus sinensis (L) Osbeck). Quantitative proteomics revealed global changes in the citrus proteome after CLas inoculation. Plant metabolism and translation were suppressed, whereas defense-related proteins such as peroxidases, proteases and protease inhibitors were induced in the vasculature. Transcript accumulation and enzymatic activity of plant peroxidases in CLas infected sweet orange varieties under greenhouse and field conditions were assessed. Although peroxidase transcript accumulation was induced in CLas infected sweet orange varieties, peroxidase enzymatic activity varied. Specific serine proteases were up-regulated in Washington navel in the presence of CLas based on quantitative proteomics. Subsequent activity-based protein profiling revealed increased activity of two serine proteases, and reduced activity of one protease in two C. sinensis sweet orange varieties under greenhouse and field conditions. The observations in the current study highlight global reprogramming of the citrus vascular proteome and differential regulation of enzyme classes in response to CLas infection. These results open an avenue for further investigation of diverse responses to HLB across different environmental conditions and citrus genotypes.
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Affiliation(s)
- Jessica Y Franco
- Department of Plant Pathology, University of California, Davis, California, USA
| | - Shree P Thapa
- Department of Plant Pathology, University of California, Davis, California, USA
| | - Zhiqian Pang
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, USA
| | - Fatta B Gurung
- Citrus Center, Texas A&M University- Kingsville, Weslaco, Texas, USA
| | - Thomas W H Liebrand
- Department of Plant Pathology, University of California, Davis, California, USA
| | - Danielle M Stevens
- Department of Plant Pathology, University of California, Davis, California, USA
| | - Veronica Ancona
- Citrus Center, Texas A&M University- Kingsville, Weslaco, Texas, USA
| | - Nian Wang
- Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, USA
| | - Gitta Coaker
- Department of Plant Pathology, University of California, Davis, California, USA.
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40
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Zhang C, Du P, Yan H, Zhu Z, Wang X, Li W. A Sec-Dependent Secretory Protein of the Huanglongbing-Associated Pathogen Suppresses Hypersensitive Cell Death in Nicotiana benthamiana. Front Microbiol 2020; 11:594669. [PMID: 33329478 PMCID: PMC7734103 DOI: 10.3389/fmicb.2020.594669] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 11/04/2020] [Indexed: 11/13/2022] Open
Abstract
"Candidatus Liberibacter asiaticus" (CLas) is a phloem-restricted Gram-negative bacterium that is the causal agent of citrus huanglongbing (HLB). In this study, we identified a CLas-encoded Sec-dependent secretory protein CLIBASIA_04405 that could contribute to the pathogenicity of this bacterium. The gene expression level of CLIBASIA_04405 was significantly higher in citrus than in psyllids. Transient overexpression of the mature CLIBASIA_04405 protein (m4405) in Nicotiana benthamiana leaves could suppress hypersensitive response (HR)-based cell death and H2O2 accumulation triggered by the mouse BAX and the Phytophthora infestans INF1. An alanine-substitution mutagenesis assay revealed the essential of amino acid clusters EKR45-47 and DE64-65 in cell death suppression. Challenge inoculation of the transgenic N. benthamiana-expressing m4405 with Pseudomonas syringae DC3000ΔhopQ1-1 demonstrated the greatly reduced bacterial proliferation. Remarkably, transcriptome profiling and RT-qPCR analysis disclosed that the gene expression of six small heat shock proteins (sHSPs), a set of plant defense regulators, were significantly elevated in the transgenic m4405 lines compared with those in wild-type N. benthamiana. In addition, the transgenic m4405 lines displayed phenotypes of dwarfism and leaf deformation. Altogether, these data indicated that m4405 was a virulence factor of CLas.
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Affiliation(s)
- Chao Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Peixiu Du
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hailin Yan
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.,College of Plant Science, Tarim University, Alar, China
| | - Zongcai Zhu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.,College of Plant Science, Tarim University, Alar, China
| | - Xuefeng Wang
- Citrus Research Institute, Southwest University, Chongqing, China
| | - Weimin Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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Zhou Y, Wei X, Li Y, Liu Z, Duan Y, Zou H. ' Candidatus Liberibacter Asiaticus' SDE1 Effector Induces Huanglongbing Chlorosis by Downregulating Host DDX3 Gene. Int J Mol Sci 2020; 21:E7996. [PMID: 33121168 PMCID: PMC7662370 DOI: 10.3390/ijms21217996] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 10/25/2020] [Indexed: 11/21/2022] Open
Abstract
'Candidatus Liberibacter asiaticus' (CLas) is the pathogenic bacterium that causes the disease Huanglongbing (HLB) in citrus and some model plants, such as Nicotiana benthamiana. After infection, CLas releases a set of effectors to modulate host responses. One of these critical effectors is Sec-delivered effector 1 (SDE1), which induces chlorosis and cell death in N. benthamiana. In this study, we revealed the DEAD-box RNA helicase (DDX3) interacts with SDE1. Gene silencing study revealed that knockdown of the NbDDX3 gene triggers leaf chlorosis, mimicking the primary symptom of CLas infection in N. benthamiana. The interactions between SDE1 and NbDDX3 were localized in the cell membrane. Overexpression of SDE1 resulted in suppression of NbDDX3 gene expression in N. benthamiana, which suggests a critical role of SDE1 in modulating NbDDX3 expression. Furthermore, we verified the interaction of SDE1 with citrus DDX3 (CsDDX3), and demonstrated that the expression of the CsDDX3 gene was significantly reduced in HLB-affected yellowing and mottled leaves of citrus. Thus, we provide molecular evidence that the downregulation of the host DDX3 gene is a crucial mechanism of leaf chlorosis in HLB-affected plants. The identification of CsDDX3 as a critical target of SDE1 and its association with HLB symptom development indicates that the DDX3 gene is an important target for gene editing, to interrupt the interaction between DDX3 and SDE1, and therefore interfere host susceptibility.
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Affiliation(s)
- Yinghui Zhou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.Z.); (Y.L.); (Z.L.)
| | - Xiangying Wei
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China;
- U.S. Horticultural Research Laboratory, Agricultural Research Service, United States Department of Agriculture, Fort Pierce, FL 34945, USA;
| | - Yanjiao Li
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.Z.); (Y.L.); (Z.L.)
| | - Zhiqin Liu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.Z.); (Y.L.); (Z.L.)
| | - Yongping Duan
- U.S. Horticultural Research Laboratory, Agricultural Research Service, United States Department of Agriculture, Fort Pierce, FL 34945, USA;
| | - Huasong Zou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (Y.Z.); (Y.L.); (Z.L.)
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42
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Molki B, Call DR, Ha PT, Omsland A, Gang DR, Lindemann SR, Killiny N, Beyenal H. Growth of ' Candidatus Liberibacter asiaticus' in a host-free microbial culture is associated with microbial community composition. Enzyme Microb Technol 2020; 142:109691. [PMID: 33220870 DOI: 10.1016/j.enzmictec.2020.109691] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 09/22/2020] [Accepted: 10/12/2020] [Indexed: 11/19/2022]
Abstract
'Candidatus Liberibacter asiaticus' ('Ca. L. asiaticus'), the suspected causative agent of citrus greening disease, is one of many phloem-restricted plant pathogens that have not been isolated and grown in an axenic culture. In this study, infected Asian citrus psyllids were used to prepare a host-free source of 'Ca. L. asiaticus'. Host-free mixed microbial cultures of 'Ca. L. asiaticus' were grown in the presence of various antibiotic treatments to alter the composition of the microbial communities. Our hypothesis was that the presence of selected antibiotics would enhance or reduce the presence of 'Ca. L. asiaticus' in a host-free culture composed of a mixed bacterial population through changes in the microbial community structure. We determined how 'Ca. L. asiaticus' growth changed with the various treatments. Treatment with vancomycin (50 μg/mL), streptomycin (0.02 μg/mL), or polymyxin B (4 μg/mL) was associated with an increased abundance of 'Ca. L. asiaticus' of 7.35 ± 0.27, 5.56 ± 0.15, or 4.54 ± 0.83 fold, respectively, compared to untreated mixed microbial cultures, while treatment with 100 μg/mL vancomycin; 0.5, 1, or 2 μg/mL streptomycin; or 0.5 μg/mL of polymyxin B was associated with reduced growth. In addition, the growth of 'Ca. L. asiaticus' was associated with the microbial community composition of the mixed microbial cultures. A positive relationship between the presence of the Pseudomonadaceae family and 'Ca. L. asiaticus' growth was observed, while the presence of 'Ca. L. asiaticus' was below the detection limit in cultures that displayed high abundances of Bacillus cereus. Our findings offer strategies for developing effective axenic culture conditions and suggest that enrichment of the Bacillaceae family could serve as a paratransgenic approach to controlling citrus greening disease.
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Affiliation(s)
- Banafsheh Molki
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA
| | - Douglas R Call
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
| | - Phuc T Ha
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA
| | - Anders Omsland
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
| | - David R Gang
- Institute of Biological Chemistry, Washington State University, Pullman, WA, USA
| | | | - Nabil Killiny
- Department of Plant Pathology, Citrus Research and Education Center, IFAS, University of Florida, Lake Alfred, FL, USA
| | - Haluk Beyenal
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, USA.
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43
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Liu XQ, Jiang HB, Liu TY, Yang L, Fan JY, Xiong Y, Jing TX, Lou BH, Dou W, Wang JJ. A Transcriptomic and Proteomic Analysis of the Diaphorina citri Salivary Glands Reveals Genes Responding to Candidatus Liberibacter asiaticus. Front Physiol 2020; 11:582505. [PMID: 33101062 PMCID: PMC7546269 DOI: 10.3389/fphys.2020.582505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 09/02/2020] [Indexed: 01/01/2023] Open
Abstract
The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is the principal vector of the Candidatus Liberibacter asiaticus (CLas) bacterium that causes Huanglongbing (HLB) disease. The D. citri salivary glands (SG) is an important barrier to the transmission of CLas. Despite its importance, the transcriptome and proteome of SG defense against CLas are unstudied in D. citri. In the present study, we generated a comparative transcriptome dataset of the SG in infected and uninfected D. citri using an Illumina RNA-Seq technology. We obtained 407 differentially expressed genes (DEGs), including 159 upregulated DEGs and 248 downregulated DEGs. Functional categories showed that many DEGs were associated with the ribosome, the insecticide resistance, the immune response and the digestion in comparison with CLas-infected SG and CLas-free SG. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases confirmed that metabolism and immunity were important functions in the SG. Among the DEGs, 68 genes (35 upregulated and 33 downregulated) encoding putative-secreted proteins were obtained with a signal peptide, suggesting that these genes may play important roles in CLas infection. A total of 673 SG proteins were identified in uninfected D. citri by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis, and 30 DEGs (15 upregulated and 15 downregulated) were found using the local tBLASTP programs. Among the 30 DEGs, many DEGs mainly involved in the metabolism and cellular processes pathways. This study provides basic transcriptome and proteome information for the SG in D. citri, and helps illuminate the molecular interactions between CLas and D. citri.
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Affiliation(s)
- Xiao-Qiang Liu
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Hong-Bo Jiang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Tian-Yuan Liu
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Li Yang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Jia-Yao Fan
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Ying Xiong
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Tian-Xing Jing
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Bing-Hai Lou
- Guangxi Key Laboratory of Citrus Biology, Guangxi Citrus Research Institute, Gulin, China
| | - Wei Dou
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Jin-Jun Wang
- Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.,International Joint Laboratory of China-Belgium on Sustainable Crop Pest Control, Academy of Agricultural Sciences, Southwest University, Chongqing, China
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Chen XD, Ebert TA, Pelz-Stelinski KS, Stelinski LL. Fitness costs associated with thiamethoxam and imidacloprid resistance in three field populations of Diaphorina citri (Hemiptera: Liviidae) from Florida. Bull Entomol Res 2020; 110:512-520. [PMID: 32046801 DOI: 10.1017/s0007485319000907] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Insecticide resistance is an increasing problem in citrus production. The Asian citrus psyllid, Diaphornia citri Kuwayama, is recognized as one of the most important citrus pests worldwide and it has developed resistance in areas where insecticides have been overused. The development of insecticide resistance is often associated with fitness costs that only become apparent in the absence of selection pressure. Here, the fitness costs associated with resistance to thiamethoxam and imidacloprid were investigated in three agricultural populations of D. citri as compared with susceptible laboratory colonies. Results showed that all field populations had greater resistance than laboratory susceptible colonies. For both thiamethoxam and imidacloprid, a Candidatus Liberibacter asiaticus-positive (CLas+) colony was more susceptible than the CLas- colony. Resistance ratios ranged from 7.65-16.11 for imidacloprid and 26.79-49.09 for thiamethoxam in field populations as compared with a susceptible, CLas- laboratory strain. Among three resistant field populations, a significantly reduced net reproductive rate and finite rate of population increase were observed in a population from Lake Wales, FL as compared to both susceptible strains. The fecundity of field populations from Lake Wales, FL was statistically lower than both laboratory susceptible populations. Certain changes in morphological characteristics were observed among resistant, as compared, with susceptible strains. Our data suggest fitness disadvantages associated with insecticide resistance in D. citri are related to both development and reproduction. The lower fitness of D. citri populations that exhibit resistance to neonicotinoid insecticides should promote recovery of sensitivity when those populations are no longer exposed to thiamethoxam and/or imidacloprid in the field. The results are congruent with a strategy of insecticide rotation for resistance management.
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Affiliation(s)
- Xue Dong Chen
- Entomology and Nematology Department, University of Florida, Citrus Research and Education Center, 700 Experiment station Rd, Lake Alfred, FL, 33850, USA
| | - Timothy A Ebert
- Horticulture Department, University of Florida, Citrus Research and Education Center, 700 Experiment station, Lake Alfred, FL, 33850, USA
| | - Kirsten S Pelz-Stelinski
- Entomology and Nematology Department, University of Florida, Citrus Research and Education Center, 700 Experiment station Rd, Lake Alfred, FL, 33850, USA
| | - Lukasz L Stelinski
- Entomology and Nematology Department, University of Florida, Citrus Research and Education Center, 700 Experiment station Rd, Lake Alfred, FL, 33850, USA
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45
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Ramsey JS, Chin EL, Chavez JD, Saha S, Mischuk D, Mahoney J, Mohr J, Robison FM, Mitrovic E, Xu Y, Strickler SR, Fernandez N, Zhong X, Polek M, Godfrey KE, Giovannoni JJ, Mueller LA, Slupsky CM, Bruce JE, Heck M. Longitudinal Transcriptomic, Proteomic, and Metabolomic Analysis of Citrus limon Response to Graft Inoculation by Candidatus Liberibacter asiaticus. J Proteome Res 2020; 19:2247-2263. [PMID: 32338516 PMCID: PMC7970439 DOI: 10.1021/acs.jproteome.9b00802] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Presymptomatic detection of citrus trees infected with Candidatus Liberibacter asiaticus (CLas), the bacterial pathogen associated with Huanglongbing (HLB; citrus greening disease), is critical to controlling the spread of the disease. To test whether infected citrus trees produce systemic signals that may be used for indirect disease detection, lemon (Citrus limon) plants were graft-inoculated with either CLas-infected or control (CLas-) budwood, and leaf samples were longitudinally collected over 46 weeks and analyzed for plant changes associated with CLas infection. RNA, protein, and metabolite samples extracted from leaves were analyzed using RNA-Seq, mass spectrometry, and 1H NMR spectroscopy, respectively. Significant differences in specific transcripts, proteins, and metabolites were observed between CLas-infected and control plants as early as 2 weeks post graft (wpg). The most dramatic differences between the transcriptome and proteome of CLas-infected and control plants were observed at 10 wpg, including coordinated increases in transcripts and proteins of citrus orthologs of known plant defense genes. This integrated approach to quantifying plant molecular changes in leaves of CLas-infected plants supports the development of diagnostic technology for presymptomatic or early disease detection as part of efforts to control the spread of HLB into uninfected citrus groves.
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Affiliation(s)
- John S Ramsey
- USDA Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, New York 14853, United States
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Elizabeth L Chin
- Department of Food Science and Technology, University of California, 392 Old Davis Road, Davis, California 95616, United States
| | - Juan D Chavez
- Department of Genome Sciences, University of Washington, William H. Foege Hall, 3720 15th Avenue NE, Seattle, Washington 98195, United States
| | - Surya Saha
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Darya Mischuk
- Department of Food Science and Technology, University of California, 392 Old Davis Road, Davis, California 95616, United States
| | - Jaclyn Mahoney
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Jared Mohr
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
- Department of Genome Sciences, University of Washington, William H. Foege Hall, 3720 15th Avenue NE, Seattle, Washington 98195, United States
| | - Faith M Robison
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Elizabeth Mitrovic
- Contained Research Facility, University of California, 555 Hopkins Road, Davis, California 95616, United States
| | - Yimin Xu
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Susan R Strickler
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Noe Fernandez
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Xuefei Zhong
- Department of Genome Sciences, University of Washington, William H. Foege Hall, 3720 15th Avenue NE, Seattle, Washington 98195, United States
| | - MaryLou Polek
- Citrus Research Board, 217 N Encina Street, Visalia, California 93291, United States
- National Clonal Germplasm Repository for Citrus, 1060 Martin Luther King Blvd., Riverside, California 92507, United States
| | - Kris E Godfrey
- Contained Research Facility, University of California, 555 Hopkins Road, Davis, California 95616, United States
| | - James J Giovannoni
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
- USDA Plant, Soil, and Nutrition Research Unit, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, New York 14853, United States
- Plant Biology Section, School of Integrative Plant Science, Cornell University, 236 Tower Road, Ithaca, New York 14853, United States
| | - Lukas A Mueller
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
| | - Carolyn M Slupsky
- Department of Food Science and Technology, University of California, 392 Old Davis Road, Davis, California 95616, United States
| | - James E Bruce
- Department of Genome Sciences, University of Washington, William H. Foege Hall, 3720 15th Avenue NE, Seattle, Washington 98195, United States
| | - Michelle Heck
- USDA Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, New York 14853, United States
- Boyce Thompson Institute for Plant Research, 533 Tower Road, Ithaca, New York 14853, United States
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, 236 Tower Road, Ithaca, New York 14853, United States
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Nan J, Zhang S, Zhan P, Jiang L. Evaluation of Bronopol and Disulfiram as Potential Candidatus Liberibacter asiaticus Inosine 5'-Monophosphate Dehydrogenase Inhibitors by Using Molecular Docking and Enzyme Kinetic. Molecules 2020; 25:E2313. [PMID: 32423116 PMCID: PMC7287799 DOI: 10.3390/molecules25102313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 04/30/2020] [Accepted: 05/11/2020] [Indexed: 12/12/2022] Open
Abstract
Citrus huanglongbing (HLB) is a destructive disease that causes significant damage to many citrus producing areas worldwide. To date, no strategy against this disease has been established. Inosine 5'-monophosphate dehydrogenase (IMPDH) plays crucial roles in the de novo synthesis of guanine nucleotides. This enzyme is used as a potential target to treat bacterial infection. In this study, the crystal structure of a deletion mutant of CLas IMPDHΔ98-201 in the apo form was determined. Eight known bioactive compounds were used as ligands for molecular docking. The results showed that bronopol and disulfiram bound to CLas IMPDHΔ98-201 with high affinity. These compounds were tested for their inhibition against CLas IMPDHΔ98-201 activity. Bronopol and disulfiram showed high inhibition at nanomolar concentrations, and bronopol was found to be the most potent molecule (Ki = 234 nM). The Ki value of disulfiram was 616 nM. These results suggest that bronopol and disulfiram can be considered potential candidate agents for the development of CLas inhibitors.
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Affiliation(s)
- Jing Nan
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Shaoran Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Ping Zhan
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
| | - Ling Jiang
- College of Horticulture and Forestry, Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (J.N.); (P.Z.)
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Atta AA, Morgan KT, Hamido SA, Kadyampakeni DM. Effect of Essential Nutrients on Roots Growth and Lifespan of Huanglongbing Affected Citrus Trees. Plants (Basel) 2020; 9:plants9040483. [PMID: 32283776 PMCID: PMC7238226 DOI: 10.3390/plants9040483] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/05/2020] [Accepted: 04/06/2020] [Indexed: 12/02/2022]
Abstract
Understanding citrus tree root development and dynamics are critical in determining crop best nutrient management practices. The role of calcium (Ca) and magnesium (Mg), manganese (Mn), Zinc (Zn), and boron (B) on huanglongbing (HLB) affected citrus trees’ root growth and lifespan in Florida is not fully documented. Thus, the objective of this study was to determine the impact of foliar and ground-applied essential nutrients on seasonal fine root length density (FRLD; diameter (d) < 2 mm) and coarse roots (d > 2 mm), FRLD dynamics, root survival probability (lifespan), and root-zone soil pH of HLB-affected sweet orange trees. Results indicated that Ca treated trees budded on Cleopatra (Cleo) and Ca and Mg combined treatments on Swingle (Swc) rootstocks significantly increased seasonal FRLD of fine (< 2 mm) and coarse roots. The highest median root lifespan of Ca treated trees was 325 and 339 days for trees budded on Cleo and Swc rootstocks, respectively. In the second study, the coarse roots showed a significantly higher reaction to the nutrition applied than the fine roots. Meanwhile, the 2× (1× foliar and 1× ground-applied) treated trees showed a significantly higher median root lifespan compared to the other treatments. Thus, the current study unwraps future studies highlighting the combined soil and/or foliar application of the above nutrients to stimulate FRLD and improve root lifespan on HLB-affected sweet oranges with emphasis on root-zone soil pH.
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Affiliation(s)
- Alisheikh A. Atta
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (S.A.H.)
- Correspondence:
| | - Kelly T. Morgan
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (S.A.H.)
| | - Said A. Hamido
- Southwest Florida Research and Education Center, University of Florida, 2685 SR 29 N, Immokalee, FL 34142, USA; (K.T.M.); (S.A.H.)
| | - Davie M. Kadyampakeni
- Citrus Research and Education Center, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA;
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Arce-Leal ÁP, Bautista R, Rodríguez-Negrete EA, Manzanilla-Ramírez MÁ, Velázquez-Monreal JJ, Méndez-Lozano J, Bejarano ER, Castillo AG, Claros MG, Leyva-López NE. De novo assembly and functional annotation of Citrus aurantifolia transcriptome from Candidatus Liberibacter asiaticus infected and non-infected trees. Data Brief 2020; 29:105198. [PMID: 32071978 PMCID: PMC7011030 DOI: 10.1016/j.dib.2020.105198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/07/2020] [Accepted: 01/20/2020] [Indexed: 12/03/2022] Open
Abstract
Mexican lime (Citrus aurantifolia) belongs to the Rutaceae family and nowadays is one of the major commercial citrus crops in different countries. In Mexico, Mexican lime production is impaired by Huanglongbing (HLB) disease associated to Candidatus Liberibacter asiaticus (CLas) bacteria. To date, transcriptomic studies of CLas-Citrus interaction, have been performed mainly in sweet citrus models at symptomatic (early) stage where pleiotropic responses could mask important, pathogen-driven host modulation as well as, host antibacterial responses. Additionally, well-assembled reference transcriptomes for acid limes including C. aurantifolia are not available. The development of improved transcriptomic resources for CLas-citrus pathosystem, including both asymptomatic (early) and symptomatic (late) stages, could accelerate the understanding of the disease. Here, we provide the first transcriptomic analysis from healthy and HLB-infected C. aurantifolia leaves at both asymptomatic and symptomatic stages, using a RNA-seq approach in the Illumina NexSeq500 platform. The construction of the assembled transcriptome was conducted using the predesigned workflow Transflow and a total of 41,522 tentative transcripts (TTs) obtained. These C. aurantifolia TTs were functionally annotated using TAIR10 and UniProtKB databases. All raw reads were deposited in the NCBI SRA with accession numbers SRR10353556, SRR10353558, SRR10353560 and SRR10353562. Overall, this dataset adds new transcriptomic valuable tools for future breeding programs, will allow the design of novel diagnostic molecular markers, and will be an essential tool for studying the HLB disease.
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Affiliation(s)
- Ángela Paulina Arce-Leal
- Instituto Politécnico Nacional, CIIDIR-Unidad Sinaloa, Departamento de Biotecnología Agrícola, Mexico
| | - Rocío Bautista
- Plataforma Andaluza de Bioinformática, Universidad de Málaga, Malaga, Spain
| | - Edgar A Rodríguez-Negrete
- CONACyT, Instituto Politécnico Nacional, CIIDIR-Unidad Sinaloa, Departamento de Biotecnología Agrícola, Mexico
| | | | | | - Jesús Méndez-Lozano
- Instituto Politécnico Nacional, CIIDIR-Unidad Sinaloa, Departamento de Biotecnología Agrícola, Mexico
| | - Eduardo R Bejarano
- Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora (IHSM-UMA-CSIC), Área de Genética, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
| | - Araceli G Castillo
- Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora (IHSM-UMA-CSIC), Área de Genética, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain
| | - M Gonzalo Claros
- Plataforma Andaluza de Bioinformática, Universidad de Málaga, Malaga, Spain.,Departamento de Biología Molecular y Bioquímica, Universidad de Málaga, Malaga, Spain
| | - Norma Elena Leyva-López
- Instituto Politécnico Nacional, CIIDIR-Unidad Sinaloa, Departamento de Biotecnología Agrícola, Mexico
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Britt K, Gebben S, Levy A, Al Rwahnih M, Batuman O. The Detection and Surveillance of Asian Citrus Psyllid ( Diaphorina citri)-Associated Viruses in Florida Citrus Groves. Front Plant Sci 2020; 10:1687. [PMID: 32010169 PMCID: PMC6978739 DOI: 10.3389/fpls.2019.01687] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 11/29/2019] [Indexed: 05/26/2023]
Abstract
The plant pathogenic bacterium Candidatus Liberibacter asiaticus (CLas), the causal agent of the citrus disease Huanglongbing (HLB), and its insect vector, the Asian citrus psyllid (ACP; Diaphorina citri), have been devastating the Florida citrus industry. To restore the competitive production presence of Florida in the worldwide citrus market, effective and sustainable control of HLB and the ACP needs to be identified. As alternatives for resistance-inducing insecticides, viruses are currently being considered for biological control of the ACP. To identify possible biological control candidates, we conducted one of the most comprehensive surveys of natural ACP populations in major citrus production regions spanning 21 counties in Florida. By optimizing PCRs and RT-PCRs, we were able to successfully detect and monitor the prevalence of five previously identified ACP-associated RNA and DNA viruses throughout Florida citrus groves, which include: Diaphorina citri-associated C virus (DcACV), Diaphorina citri flavi-like virus (DcFLV), Diaphorina citri densovirus (DcDNV), Diaphorina citri reovirus (DcRV), and Diaphorina citri picorna-like virus (DcPLV). Adult and nymph ACP populations from 21 of Florida's major citrus-producing counties were collected each month during approximately 18 consecutive months. RNA extracts used for these viral screens were also regionally combined and subjected to High Throughput Sequencing (HTS) to reveal a more comprehensive picture of known and unknown viruses in Florida ACP populations. We discovered that DcACV was the most prevalent ACP-associated virus throughout nymph and adult ACP populations in Florida, detected in more than 60% of all samples tested, followed by DcPLV and DcFLV. HTS allowed us to identify a novel ACP-associated reo-like virus and a picorna-like virus. The putative reo-like virus, tentatively named Diaphorina citri cimodo-like virus, was later surveyed and detected back in seasonal adult and nymph ACP samples collected in Florida during this study. HTS generated data also revealed that the most abundant virus in Florida ACP populations was Citrus tristeza virus (CTV), which is not an ACP-associated virus, suggesting persistent presence of CTV infection in citrus throughout Florida groves. Collectively, information obtained from our study may be able to help guide the direction of biotechnological pest control efforts involving a number of viruses that were detected for the first time in Florida ACP populations, including two newly identified ACP-associated viruses.
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Affiliation(s)
- Kellee Britt
- Department of Plant Pathology, Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, United States
| | - Samantha Gebben
- Department of Plant Pathology, Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, United States
| | - Amit Levy
- Department of Plant Pathology, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Maher Al Rwahnih
- Department of Plant Pathology, University of California-Davis, Davis, CA, United States
| | - Ozgur Batuman
- Department of Plant Pathology, Southwest Florida Research and Education Center, University of Florida, Immokalee, FL, United States
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Chin EL, Ramsey JS, Mishchuk DO, Saha S, Foster E, Chavez JD, Howe K, Zhong X, Polek M, Godfrey KE, Mueller LA, Bruce JE, Heck M, Slupsky CM. Longitudinal Transcriptomic, Proteomic, and Metabolomic Analyses of Citrus sinensis (L.) Osbeck Graft-Inoculated with " Candidatus Liberibacter asiaticus". J Proteome Res 2020; 19:719-732. [PMID: 31885275 DOI: 10.1021/acs.jproteome.9b00616] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
"Candidatus Liberibacter asiaticus" (CLas) is the bacterium associated with the citrus disease Huanglongbing (HLB). Current CLas detection methods are unreliable during presymptomatic infection, and understanding CLas pathogenicity to help develop new detection techniques is challenging because CLas has yet to be isolated in pure culture. To understand how CLas affects citrus metabolism and whether infected plants produce systemic signals that can be used to develop improved detection techniques, leaves from Washington Navel orange (Citrus sinensis (L.) Osbeck) plants were graft-inoculated with CLas and longitudinally studied using transcriptomics (RNA sequencing), proteomics (liquid chromatography-tandem mass spectrometry), and metabolomics (proton nuclear magnetic resonance). Photosynthesis gene expression and protein levels were lower in infected plants compared to controls during late infection, and lower levels of photosynthesis proteins were identified as early as 8 weeks post-grafting. These changes coordinated with higher sugar concentrations, which have been shown to accumulate during HLB. Cell wall modification and degradation gene expression and proteins were higher in infected plants during late infection. Changes in gene expression and proteins related to plant defense were observed in infected plants as early as 8 weeks post-grafting. These results reveal coordinated changes in greenhouse navel leaves during CLas infection at the transcript, protein, and metabolite levels, which can inform of biomarkers of early infection.
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Affiliation(s)
- Elizabeth L Chin
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
| | - John S Ramsey
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Darya O Mishchuk
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
| | - Surya Saha
- Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Elizabeth Foster
- Contained Research Facility , University of California, Davis , Davis , California 95616 , United States
| | - Juan D Chavez
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - Kevin Howe
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - Xuefei Zhong
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - MaryLou Polek
- National Clonal Germplasm Repository for Citrus & Dates , Riverside , California 92507 , United States
| | - Kris E Godfrey
- Contained Research Facility , University of California, Davis , Davis , California 95616 , United States
| | - Lukas A Mueller
- Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States
| | - James E Bruce
- Department of Genome Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - Michelle Heck
- Emerging Pests and Pathogens Research Unit, Robert W. Holley Center for Agriculture and Health , USDA Agricultural Research Service , Ithaca , New York 14853 , United States.,Boyce Thompson Institute for Plant Research , Ithaca , New York 14853 , United States.,Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science , Cornell University , Ithaca , New York 14853 , United States
| | - Carolyn M Slupsky
- Department of Food Science and Technology , University of California, Davis , Davis , California 95616 , United States
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