1
|
Zhao X, Zhao Z, Cheng S, Wang L, Luo Z, Ai C, Liu Z, Liu P, Wang L, Wang J, Liu M, Li Y, Liu M. ZjWRKY23 and ZjWRKY40 Promote Fruit Size Enlargement by Targeting and Downregulating Cytokinin Oxidase/Dehydrogenase 5 Expression in Chinese Jujube. J Agric Food Chem 2023; 71:18046-18058. [PMID: 37957030 DOI: 10.1021/acs.jafc.3c04377] [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] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
Fruit size is crucial for fruit trees, as it contributes to both quality and yield. However, the underlying mechanism of fruit size regulation remains largely unknown. Taking advantage of using a fruit double-sized bud mutant of Chinese jujube, "Jinkuiwang" and its wild type, "Jinsixiaozao", we carried out a comprehensive study on the mechanism of fruit size development in jujube. Using weighted gene coexpression network analyses, a number of candidate regulators for fruit size including those involved in hormonal signaling pathways, transcription factors, and heat shock proteins were identified. A hub gene named cytokinin oxidase/dehydrogenase 5 (ZjCKX5), responsible for cytokinin degradation, was found to play a negative role in regulating fruit size development, and overexpressing ZjCKX5 in tomato and Arabidopsis resulted in much smaller fruits and dwarf plants. Furthermore, another two hub genes, ZjWRKY23 and ZjWRKY40 transcription factors, were found to participate in fruit size regulation by targeting and downregulating the ZjCKX5 expression. Overexpressing ZjWRKY23 or ZjWRKY40 in tomato led to much larger fruits and promoted plant architecture. Based on these results, a molecular framework for jujube fruit size regulation, namely, ZjWRKY-ZjCKX5 module, was proposed. This study provides a new insight into the molecular networks underlying fruit size regulation.
Collapse
Affiliation(s)
- Xuan Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Zixuan Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Shasha Cheng
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Lihu Wang
- School of Landscape and Ecological Engineering, Hebei University of Engineering, Handan, Hebei 056038, China
| | - Zhi Luo
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Changfeng Ai
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Zhiguo Liu
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Ping Liu
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Lili Wang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Jiurui Wang
- College of Forestry, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Mengzhen Liu
- City Administration of Zhongjie Industrial Park in Cangzhou Bohai New Area, Cangzhou, Hebei 061108, China
| | - Yong Li
- City Administration of Zhongjie Industrial Park in Cangzhou Bohai New Area, Cangzhou, Hebei 061108, China
| | - Mengjun Liu
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| |
Collapse
|
2
|
Xue X, Zhao A, Wang Y, Ren H, Su W, Li Y, Shi M, Liu L, Li D. Metabolomics and transcriptomics analyses for characterizing the alkaloid metabolism of Chinese jujube and sour jujube fruits. Front Plant Sci 2023; 14:1267758. [PMID: 37790781 PMCID: PMC10544937 DOI: 10.3389/fpls.2023.1267758] [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: 07/27/2023] [Accepted: 08/24/2023] [Indexed: 10/05/2023]
Abstract
Introduction Jujube is an important economic forest tree whose fruit is rich in alkaloids. Chinese jujube (Ziziphus jujuba Mill.) and sour jujube (Ziziphus spinosa Hu.) are the two most important species of the jujube genus. However, the mechanisms underlying the synthesis and metabolism of alkaloids in jujube fruits remain poorly understood. Methods In this study, the fruits of Ziziphus jujuba 'Hupingzao' and Ziziphus spinosa 'Taigusuanzao' in different harvest stages were used as test materials, we first integrated widely targeted metabolomics and transcriptomics analyses to elucidate the metabolism of alkaloids of jujube fruits. Results In the metabolomics analysis, 44 alkaloid metabolites were identified in 4 samples, 3 of which were unique to sour jujube fruit. The differential alkaloid metabolites (DAMs) were more accumulated in sour jujube than in Chinese jujube; further, they were more accumulated in the white ripening stage than in the red stage. DAMs were annotated to 12 metabolic pathways. Additionally, transcriptomics data revealed 259 differentially expressed genes (DEGs) involved in alkaloid synthesis and metabolism. By mapping the regulatory networks of DAMs and DEGs, we screened out important metabolites and 11 candidate genes. Discussion This study preliminarily elucidated the molecular mechanism of jujube alkaloid synthesis. The candidate genes regulated the synthesis of key alkaloid metabolites, but the specific regulation mechanism is unclear. Taken together, our results provide insights into the metabolic networks of alkaloid synthesis in Chinese jujube and sour jujube fruits at different harvest stages, thereby providing a theoretical reference for further research on the regulatory mechanism of jujube alkaloids and their development and utilization.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Dengke Li
- Pomology Institute, Shanxi Agricultural University, Shanxi Key Laboratory of Germplasm Improvement and Utilization in Pomology, Taiyuan, China
| |
Collapse
|
3
|
Luo Z, Gao M, Zhao X, Wang L, Liu Z, Wang L, Wang L, Zhao J, Wang J, Liu M. Anatomical observation and transcriptome analysis of branch-twisted mutations in Chinese jujube. BMC Genomics 2023; 24:500. [PMID: 37644409 PMCID: PMC10466873 DOI: 10.1186/s12864-023-09572-2] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 08/09/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND Plant organs grow in a certain direction and organ twisted growth, a rare and distinctive trait, is associated with internal structure changes and special genes. The twisted branch mutant of Chinese jujube jujube, an important fruit tree native to China and introduced to nearly 50 countries, provides new typical materials for exploration of plant twisted growth. RESULTS In this study, the cytological characteristics and related genes of twisted branches in Chinese jujube were revealed by microscopy observation and transcriptome analysis. The unique coexistence of primary and secondary structures appeared in the twisted parts of branches, and special structures such as collateral bundle, cortical bundles, and internal phloem were formed. Ninety differentially expressed genes of 'Dongzao' and its twisted mutant were observed, in which ZjTBL43, ZjFLA11, ZjFLA12 and ZjIQD1 were selected as candidate genes. ZjTBL43 was homologous to AtTBL43 in Arabidopsis, which was involved in the synthesis and deposition of cellular secondary wall cellulose. The attbl43 mutant showed significant inflorescence stem bending growth. The transgenic lines of attbl43 with overexpression of ZjTBL43 were phenotypically normal.The branch twisted growth may be caused by mutations in ZjTBL43 in Chinese jujube. AtIQD10, AtFLA11 and AtFLA12 were homologous to ZjIQD1, ZjFLA11 and ZjFLA12, respectively. However, the phenotype of their function defect mutants was normal. CONCLUSION In summary, these findings will provide new insights into the plant organ twisted growth and a reference for investigation of controlling mechanisms of plant growth direction.
Collapse
Affiliation(s)
- Zhi Luo
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Mengjiao Gao
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Xuan Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Lihu Wang
- School of Landscape and Ecological Engineering, Hebei University of Engineering, Handan, 056038, China
| | - Zhiguo Liu
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Lixin Wang
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Lili Wang
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, 071001, China.
| | - Jiurui Wang
- College of Forestry, Hebei Agricultural University, Baoding, 071001, China.
| | - Mengjun Liu
- College of Horticulture, Hebei Agricultural University, Baoding, 071001, China.
- Research Center of Chinese Jujube, College of Horticulture, Hebei Agricultural University, Baoding, 071001, China.
| |
Collapse
|
4
|
Zhang Y, Niu N, Li S, Liu Y, Xue C, Wang H, Liu M, Zhao J. Virus-Induced Gene Silencing (VIGS) in Chinese Jujube. Plants (Basel) 2023; 12:plants12112115. [PMID: 37299093 DOI: 10.3390/plants12112115] [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: 05/03/2023] [Revised: 05/23/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
Virus-induced gene silencing (VIGS) is a fast and efficient method for assaying gene function in plants. At present, the VIGS system mediated by Tobacco rattle virus (TRV) has been successfully practiced in some species such as cotton and tomato. However, little research of VIGS systems has been reported in woody plants, nor in Chinese jujube. In this study, the TRV-VIGS system of jujube was firstly investigated. The jujube seedlings were grown in a greenhouse with a 16 h light/8 h dark cycle at 23 °C. After the cotyledon was fully unfolded, Agrobacterium mixture containing pTRV1 and pTRV2-ZjCLA with OD600 = 1.5 was injected into cotyledon. After 15 days, the new leaves of jujube seedlings showed obvious photo-bleaching symptoms and significantly decreased expression of ZjCLA, indicating that the TRV-VIGS system had successfully functioned on jujube. Moreover, it found that two injections on jujube cotyledon could induce higher silencing efficiency than once injection. A similar silencing effect was then also verified in another gene, ZjPDS. These results indicate that the TRV-VIGS system in Chinese jujube has been successfully established and can be applied to evaluate gene function, providing a breakthrough in gene function verification methods.
Collapse
Affiliation(s)
- Yao Zhang
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Nazi Niu
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Shijia Li
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Yin Liu
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Huibin Wang
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071000, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
| |
Collapse
|
5
|
Wu H, Su W, Shi M, Xue X, Ren H, Wang Y, Zhao A, Li D, Liu M. Genomic C-Value Variation Analysis in Jujube ( Ziziphus jujuba Mill.) in the Middle Yellow River Basin. Plants (Basel) 2023; 12:858. [PMID: 36840207 PMCID: PMC9962250 DOI: 10.3390/plants12040858] [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: 11/01/2022] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
Chinese jujube (Ziziphus jujuba Mill.) originated in the Yellow River basin (YRB) of the Shanxi-Shaanxi region. The genomic C-value is a crucial indicator for plant breeding and germplasm evaluation. In this study, we used flow cytometry to determine the genomic C-values of jujube germplasms in the YRB of the Shanxi-Shaanxi region and evaluated their differences in different sub-regions. Of the 29 sub-regions, the highest and lowest variations were in Linxian and Xiaxian, respectively. The difference between jujube germplasms was highly significant (F = 14.89, p < 0.0001) in Linxian. Cluster analysis showed that both cluster 2 and 4 belonged to Linxian, which were clearly separated from other taxa but were cross-distributed in them. Linxian County is an important gene exchange center in the YRB of the Shanxi-Shaanxi region. Principal component analysis showed that cluster 1 had low genomic C-values and single-fruit weights and cluster 2 had high genomic C-values and vitamin C contents. The genomic C-value was correlated with single-fruit weight and vitamin C content. In addition, the genomic C-value was used to predict fruit agronomic traits, providing a reference for shortening the breeding cycle and genetic diversity-related studies of jujube germplasm.
Collapse
Affiliation(s)
- Hao Wu
- Shanxi Key Laboratory of Fruit Germplasm Creation and Utilization, Institute of Fruit Trees, Agricultural University of Shanxi, Taiyuan 030031, China
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Wanlong Su
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Meijuan Shi
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Xiaofang Xue
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Haiyan Ren
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Yongkang Wang
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Ailing Zhao
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Dengke Li
- College of Horticulture, Taigu Campus, Agricultural University of Shanxi, Jinzhong 030800, China
| | - Mengjun Liu
- College of Horticulture, Baoding Campus, Agricultural University of Hebei, Baoding 071000, China
| |
Collapse
|
6
|
Liu Z, Yuan Y, Wang L, Zhao X, Wang L, Wang L, Zhao Z, Zhao X, Chu Y, Gao Y, Yang F, Wang Y, Zhang Q, Zhao J, Liu M. Three Novel Adenylate Cyclase Genes Show Significant Biological Functions in Plant. J Agric Food Chem 2023; 71:1149-1161. [PMID: 36601683 DOI: 10.1021/acs.jafc.2c07683] [Citation(s) in RCA: 1] [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: 06/17/2023]
Abstract
Adenylate cyclase is the key enzyme solely synthesizing cAMP which participates in cell metabolism regulations and functions as an intracellular second messenger. However, the biological functions of plant ACs have not been elucidated clearly for their poor conservative sequences and low detectable cAMP. We performed a systematic study of plant ACs by using Chinese jujube, whose fruit exhibits the highest cAMP content among plants. Three novel ACs were identified from Chinese jujube, and two types of methods including in vitro and in vivo were used to certificate ZjAC1-3 which can catalyze the conversion of ATP into cAMP. The biological functions of significant accelerations of seed germination, root growth, and flowering were found via overexpression of these AC genes in Arabidopsis, and these functions of ACs were further demonstrated by treating the AC-overexpressing transgenic lines and wild type Arabidopsis with bithionol and dibutyryl-cAMP. At last, transcriptome data revealed that the underlying mechanism of the biological functions of ACs might be regulation of the key genes involved in the circadian rhythm pathway and the hormone signal transduction pathway. This research established a foundation for further investigating plant AC genes and provided strong evidence for cAMP serving as a signaling molecule in plants.
Collapse
Affiliation(s)
- Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Jujube Industry Technology Research Institute of Hebei, Baoding, Hebei 071001, China
| | - Ye Yuan
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Lili Wang
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Xuan Zhao
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
- "Dongzao" Research Institute of Zhanhua District, Binzhou, Shandong 256800, China
| | - Lixin Wang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Lihu Wang
- College of Landscape and Ecological Engineering, Hebei University of Engineering, Handan 056038, China
| | - Zhihui Zhao
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Xin Zhao
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Yuetong Chu
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Yaning Gao
- Beijing Pharma and Biotech Center, Beijing 100176, China
| | - Fangyuan Yang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Yulu Wang
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Qiong Zhang
- Shandong Institute of Pomology, Tai'an, Shandong 271000, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, Hebei 071001, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, Hebei 071001, China
- College of Horticulture, Hebei Agricultural University, Baoding, Hebei 071001, China
- Jujube Industry Technology Research Institute of Hebei, Baoding, Hebei 071001, China
| |
Collapse
|
7
|
Li M, Zhang C, Hou L, Yang W, Liu S, Pang X, Li Y. Multiple responses contribute to the enhanced drought tolerance of the autotetraploid Ziziphus jujuba Mill. var. spinosa. Cell Biosci 2021; 11:119. [PMID: 34193297 PMCID: PMC8243571 DOI: 10.1186/s13578-021-00633-1] [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: 06/21/2021] [Indexed: 12/13/2022] Open
Abstract
Background Polyploid plants often exhibit enhanced stress tolerance. The underlying physiological and molecular bases of such mechanisms remain elusive. Here, we characterized the drought tolerance of autotetraploid sour jujube at phenotypic, physiological and molecular levels. Results The study findings showed that the autotetraploid sour jujube exhibited a superior drought tolerance and enhanced regrowth potential after dehydration in comparison with the diploid counterpart. Under drought stress, more differentially expressed genes (DEGs) were detected in autotetraploid sour jujube and the physiological responses gradually triggered important functions. Through GO enrichment analysis, many DEGs between the diploid and autotetraploid sour jujube after drought-stress exposure were annotated to the oxidation–reduction process, photosystem, DNA binding transcription factor activity and oxidoreductase activity. Six reactive oxygen species scavenging-related genes were specifically differentially expressed and the larger positive fold-changes of the DEGs involved in glutathione metabolism were detected in autotetraploid. Consistently, the lower O2− level and malonaldehyde (MDA) content and higher antioxidant enzymes activity were detected in the autotetraploid under drought-stress conditions. In addition, DEGs in the autotetraploid after stress exposure were significantly enriched in anthocyanin biosynthesis, DNA replication, photosynthesis and plant hormone, including auxin, abscisic acid and gibberellin signal-transduction pathways. Under osmotic stress conditions, genes associated with the synthesis and transport of osmotic regulators including anthocyanin biosynthesis genes were differentially expressed, and the soluble sugar, soluble protein and proline contents were significantly higher in the autotetraploid. The higher chlorophyll content and DEGs enriched in photosynthesis suggest that the photosynthetic system in the autotetraploid was enhanced compared with diploid during drought stress. Moreover, several genes encoding transcription factors (TFs) including GRAS, Bhlh, MYB, WRKY and NAC were induced specifically or to higher levels in the autotetraploid under drought-stress conditions, and hub genes, LOC107403632, LOC107422279, LOC107434947, LOC107412673 and LOC107432609, related to 18 up-regulated transcription factors in the autotetraploid compared with the diploid were identified. Conclusion Taken together, multiple responses contribute to the enhanced drought tolerance of autotetraploid sour jujube. This study could provide an important basis for elucidating the mechanism of tolerance variation after the polyploidization of trees. Supplementary Information The online version contains supplementary material available at 10.1186/s13578-021-00633-1.
Collapse
Affiliation(s)
- Meng Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Chenxing Zhang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Lu Hou
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Weicong Yang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Songshan Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Xiaoming Pang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China.,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China.,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yingyue Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, 100083, China. .,National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing, 100083, China. .,College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China.
| |
Collapse
|
8
|
Xue C, Liu Z, Wang L, Li H, Gao W, Liu M, Zhao Z, Zhao J. The antioxidant defense system in Chinese jujube is triggered to cope with phytoplasma invasion. Tree Physiol 2020; 40:1437-1449. [PMID: 32483619 DOI: 10.1093/treephys/tpaa067] [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] [Received: 09/21/2019] [Revised: 04/18/2020] [Accepted: 05/27/2020] [Indexed: 05/27/2023]
Abstract
Reactive oxygen species (ROS) in plants increase dramatically under pathogen attack, and the antioxidant defense system is then triggered to protect the plant against the ROS. Jujube witches' broom disease (JWB), caused by phytoplasma, is a destructive disease of Chinese jujube. The results of fluorescence-based measurement revealed that ROS were overproduced within jujube leaves after phytoplasma invasion. Furthermore, analysis based on mRNA and metabolite levels revealed that ascorbic acid (AsA) metabolism was strengthened under phytoplasma stress. The high expression of genes involved in the AsA/glutathione (GSH) cycle and thioredoxin (Trx) synthesis in diseased leaves indicated that GSH and Trx actively respond to phytoplasma infection. Moreover, higher activities of enzymatic antioxidants and the upregulated expression of related genes were confirmed in diseased tissues. Both nonenzymatic and enzymatic antioxidants in the host jujube were strongly stimulated to cope with ROS caused by phytoplasma stress. Compared with that in the susceptible variety, the activities of glutathione S-transferase and peroxidase in the resistant variety at the earlier infection stage were higher, indicating that enzymes might be involved in the resistance to phytoplasma. These results highlight the roles of the antioxidant defense system of the host plant in the tolerance to phytoplasma invasion.
Collapse
Affiliation(s)
- Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
- Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding 071000, China
| | - Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071000, China
| | - Lihu Wang
- College of Landscape and Ecological Engineering, Hebei University of Engineering, Handan 056038, China
| | - Hongtai Li
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
- Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding 071000, China
| | - Weilin Gao
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
- Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding 071000, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071000, China
| | - Zhihui Zhao
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071000, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding 071000, China
- Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding 071000, China
| |
Collapse
|
9
|
Wang X, Xiao C, Ji C, Liu Z, Song X, Liu Y, Li C, Yan D, Li H, Qin Y, Liu X. Isolation and characterization of endophytic bacteria for controlling root rot disease of Chinese jujube. J Appl Microbiol 2020; 130:926-936. [PMID: 32777121 DOI: 10.1111/jam.14818] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/05/2020] [Accepted: 08/05/2020] [Indexed: 11/29/2022]
Abstract
AIM Fusarium oxysporum is the primary pathogen causing root rot disease that severely affects cultivation of jujube fruit in the Xinjiang province of China. The aim of this study was to identify endophytic bacteria in healthy jujube organs that could effectively suppress F. oxysporum growth. METHODS AND RESULTS Different plant organs (leaves, twigs and roots) were collected from healthy Chinese jujube cultivated in southern Xinjiang province of China. The endophytic bacterium Brevibacterium halotolerans JZ7 was selected for its strong antagonistic activity and growth-promoting characteristics. Gas-chromatography mass-spectrometry analysis showed that acetoin, 2,3-butanediol and fenretinide were the three dominant volatile organic compounds produced by strain JZ7. Fenretinide strongly suppressed spore germination of F. oxysporum in vitro. Pot experiments showed that strain JZ7 colonized both the roots and rhizosphere soil of Chinese jujube and significantly reduced F. oxysporum level in jujube rhizosphere soil. CONCLUSION We demonstrated that B. halotolerans JZ7 can be developed into a biological control agent to combat root rot disease of Chinese jujube in the Xinjiang province of China. SIGNIFICANCE AND IMPACT OF THE STUDY The suggested strategy for biological control of jujube root rot disease is fully in accordance with the current principles of sustainability.
Collapse
Affiliation(s)
- X Wang
- College of Horticulture, Shandong Agricultural Universities, Taian, Shandong, China.,Ministry of Agriculture Key Laboratory of Seaweed Fertilizers, Qingdao, China
| | - C Xiao
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - C Ji
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - Z Liu
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - X Song
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - Y Liu
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - C Li
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - D Yan
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - H Li
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| | - Y Qin
- State Key Laboratory of Bioactive Seaweed Substances, Qingdao Brightmoon Seaweed Group Co Ltd, Qingdao, China
| | - X Liu
- College of Forestry, Shandong Agricultural Universities, Taian, Shandong, China
| |
Collapse
|
10
|
Zhang Y, Gao W, Li H, Wang Y, Li D, Xue C, Liu Z, Liu M, Zhao J. Genome-wide analysis of the bZIP gene family in Chinese jujube (Ziziphus jujuba Mill.). BMC Genomics 2020; 21:483. [PMID: 32664853 PMCID: PMC7362662 DOI: 10.1186/s12864-020-06890-7] [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: 02/07/2020] [Accepted: 07/07/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Among several TF families unique to eukaryotes, the basic leucine zipper (bZIP) family is one of the most important. Chinese jujube (Ziziphus jujuba Mill.) is a popular fruit tree species in Asia, and its fruits are rich in sugar, vitamin C and so on. Analysis of the bZIP gene family of jujube has not yet been reported. In this study, ZjbZIPs were identified firstly, their expression patterns were further studied in different tissues and in response to various abiotic and phytoplasma stresses, and their protein-protein interactions were also analyzed. RESULTS At the whole genome level, 45 ZjbZIPs were identified and classified into 14 classes. The members of each class of bZIP subfamily contain a specific conserved domain in addition to the core bZIP conserved domain, which may be related to its biological function. Relative Synonymous Codon Usage (RSCU) analysis displayed low values of NTA and NCG codons in ZjbZIPs, which would be beneficial to increase the protein production and also indicated that ZjbZIPs were at a relative high methylation level. The paralogous and orthologous events occurred during the evolutionary process of ZjbZIPs. Thirty-four ZjbZIPs were mapped to but not evenly distributed among 10 pseudo- chromosomes. 30 of ZjbZIP genes showed diverse tissue-specific expression in jujube and wild jujube trees, indicating that these genes may have multiple functions. Some ZjbZIP genes were specifically analyzed and found to play important roles in the early stage of fruit development. Moreover, some ZjbZIPs that respond to phytoplasma invasion and abiotic stress environmental conditions, such as salt and low temperature, were found. Based on homology comparisons, prediction analysis and yeast two-hybrid, a protein interaction network including 42 ZjbZIPs was constructed. CONCLUSIONS The bioinformatics analyses of 45 ZjbZIPs were implemented systematically, and their expression profiles in jujube and wild jujube showed that many genes might play crucial roles during fruit ripening and in the response to phytoplasma and abiotic stresses. The protein interaction networks among ZjbZIPs could provide useful information for further functional studies.
Collapse
Affiliation(s)
- Yao Zhang
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Weilin Gao
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Hongtai Li
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Yongkang Wang
- Pomology Institute, Shanxi Academy of Agricultural Sciences, Taigu, China
| | - Dengke Li
- Pomology Institute, Shanxi Academy of Agricultural Sciences, Taigu, China
| | - Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China. .,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China.
| |
Collapse
|
11
|
Wang L, Li M, Liu Z, Dai L, Zhang M, Wang L, Zhao J, Liu M. Genome-wide identification of CNGC genes in Chinese jujube (Ziziphus jujuba Mill.) and ZjCNGC2 mediated signalling cascades in response to cold stress. BMC Genomics 2020; 21:191. [PMID: 32122304 DOI: 10.1186/s12864-020-6601-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [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: 06/06/2019] [Accepted: 02/20/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUNDS Cyclic nucleotide gated channels (CNGCs) play multifaceted roles in plant physiological processes, especially with respect to signalling processes, plant development, and responses to environmental stresses. However, little information is known about the CNGC family in the large cosmopolitan family Rhamnaceae, which has strong tolerance to biotic and abiotic stresses. RESULTS In the current study, a total of 15 ZjCNGCs which located on 7 chromosomes were firstly identified in Chinese jujube (Ziziphus jujuba Mill.), the most important species of Rhamnaceae in terms of economic and ecological values. Phylogenetic analysis showed that these ZjCNGCs could be classified into four groups, ZjCNGC12 belonged to group IVA, and ZjCNGC13, 14, 15 belonged to group IVB. In addition, the paralogous and orthologous homology duplication of ZjCNGC15 occurred during the evolutionary process. The characteristics of ZjCNGCs regarding to exon-intron numbers and post-translational modifications showed diversified structures and functions. Motif composition and protein sequence analysis revealed that the phosphate-binding cassette and hinge regions were conserved among ZjCNGCs. Prediction of the cis-acting regulatory elements and expression profiles by real-time quantitative PCR analysis showed that some of the ZjCNGCs responded to environmental changes, especially ZjCNGC2, which was significantly downregulated in response to cold stress, and ZjCNGC4 was highly induced in response to cold, salt and alkaline stresses. ZjCNGC13 and 14 were highly induced in the phytoplasma-resistant cultivar and downregulated in the susceptible cultivar. Furthermore, ZjCNGC2 could be regulated by cAMP treatment, microtubule changes and interact with ZjMAPKK4, which suggested that cAMP and microtubule might play important roles in ZjCNGC2 mediated ZjMAPKK4 signalling transduction involved in cold stress. CONCLUSIONS The identification and classification analysis of ZjCNGCs were firstly reported, and some key individual ZjCNGCs might play essential roles in the response to biotic and abiotic stresses, especially ZjCNGC2 mediated ZjMAPKK4 signalling transduction involved in cold stress. This systematic analysis could provide important information for further functional characterization of ZjCNGCs with the aim of breeding stress-resistant cultivars.
Collapse
|
12
|
Liu Z, Wang L, Xue C, Chu Y, Gao W, Zhao Y, Zhao J, Liu M. Genome-wide identification of MAPKKK genes and their responses to phytoplasma infection in Chinese jujube (Ziziphus jujuba Mill.). BMC Genomics 2020; 21:142. [PMID: 32041543 PMCID: PMC7011567 DOI: 10.1186/s12864-020-6548-6] [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: 05/15/2019] [Accepted: 01/31/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mitogen-activated protein kinase (MAPK) cascades play vital roles in signal transduction in response to a wide range of biotic and abiotic stresses. In a previous study, we identified ten ZjMAPKs and five ZjMAPKKs in the Chinese jujube genome. We found that some members of ZjMAPKs and ZjMAPKKs may play key roles in the plant's response to phytoplasma infection. However, how these ZjMAPKKs are modulated by ZjMAPKKKs during the response process has not been elucidated. Little information is available regarding MAPKKKs in Chinese jujube. RESULTS A total of 56 ZjMAPKKKs were identified in the jujube genome. All of these kinases contain the key S-TKc (serine/threonine protein kinase) domain, which is distributed among all 12 chromosomes. Phylogenetic analyses show that these ZjMAPKKKs can be classified into two subfamilies. Specifically, 41 ZjMAPKKKs belong to the Raf subfamily, and 15 belong to the MEKK subfamily. In addition, the ZjMAPKKKs in each subfamily share the same conserved motifs and gene structures. Only one pair of ZjMAPKKKs (15/16, on chromosome 5) was found to be tandemly duplicated. Using qPCR, the expression profiles of these MAPKKKs were investigated in response to infection with phytoplasma. In the three main infected tissues (witches' broom leaves, phyllody leaves, and apparently normal leaves), ZjMAPKKK26 and - 45 were significantly upregulated, and ZjMAPKKK3, - 43 and - 50 were significantly downregulated. ZjMAPKKK4, - 10, - 25 and - 44 were significantly and highly induced in sterile cultivated tissues infected by phytoplasma, while ZjMAPKKK6, - 7, - 17, - 18, - 30, - 34, - 35, - 37, - 40, - 41, - 43, - 46, - 52 and - 53 were significantly downregulated. CONCLUSIONS For the first time, we present an identification and classification analysis of ZjMAPKKKs. Some ZjMAPKKK genes may play key roles in the response to phytoplasma infection. This study provides an initial understanding of the mechanisms through which ZjMAPKKKs are involved in the response of Chinese jujube to phytoplasma infection.
Collapse
Affiliation(s)
- Zhiguo Liu
- College of Horticulture, Hebei Agricultural University, Baoding, China.,Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Lixin Wang
- College of Horticulture, Hebei Agricultural University, Baoding, China.,Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding, China.,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China
| | - Yuetong Chu
- College of Horticulture, Hebei Agricultural University, Baoding, China.,Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Weilin Gao
- College of Life Science, Hebei Agricultural University, Baoding, China.,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China
| | - Yitong Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China.,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China. .,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China.
| | - Mengjun Liu
- College of Horticulture, Hebei Agricultural University, Baoding, China. .,Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China.
| |
Collapse
|
13
|
Song L, Zheng J, Zhang L, Yan S, Huang W, He J, Liu P. Phytochemical Profiling and Fingerprint Analysis of Chinese Jujube ( Ziziphus jujuba Mill.) Leaves of 66 Cultivars from Xinjiang Province. Molecules 2019; 24:E4528. [PMID: 31835666 PMCID: PMC6943635 DOI: 10.3390/molecules24244528] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 11/22/2019] [Revised: 12/08/2019] [Accepted: 12/09/2019] [Indexed: 11/18/2022] Open
Abstract
Foliage of jujube (Ziziphus jujuba Mill.) as a byproduct of agriculture, is a traditional nutraceutical material in China. Previous studies have shown that it is a rich resource of polyphenols. However, information on its complete phenolic profile and the difference between cultivars is still limited. This study investigated and compared phytochemical profiles of leaves of 66 Chinese jujube cultivars. Forty-two compounds, including 22 flavonols, two flavanols, one flavanone, 13 derivatives of phenolic acids, three simple acids, and one unknown hexoside were identified/tentatively identified using high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry. Eight major flavonols were quantified by HPLC coupled with an ultraviolet (UV) detector. The contents of total flavonoids ranged from 2.6-25.1 mg/g dry weight (DW). Differences between cultivars were analyzed by hierarchical cluster analysis (HCA) and principal component analysis (PCA). This study presents a systematic study on the phenolic compounds in Chinese jujube leaves of different cultivars.
Collapse
Affiliation(s)
- Lijun Song
- School of Food Science and Engineering & Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou, Guangdong 510641, China;
- College of Life Science, Tarim University, Alar, Xinjiang 843300, China;
| | - Jie Zheng
- Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China;
| | - Li Zhang
- College of Life Science, Tarim University, Alar, Xinjiang 843300, China;
| | - Shijuan Yan
- Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong 510640, China; (S.Y.); (W.H.)
| | - Wenjie Huang
- Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong 510640, China; (S.Y.); (W.H.)
| | - Jun He
- Institute of Laboratory Animal Science, Jinan University, Guangzhou 510632, China;
| | - Pengzhan Liu
- School of Food Science and Engineering & Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou, Guangdong 510641, China;
| |
Collapse
|
14
|
Zhang Q, Wang L, Liu Z, Zhao Z, Zhao J, Wang Z, Zhou G, Liu P, Liu M. Transcriptome and metabolome profiling unveil the mechanisms of Ziziphus jujuba Mill. peel coloration. Food Chem 2019; 312:125903. [PMID: 31901700 DOI: 10.1016/j.foodchem.2019.125903] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [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: 09/19/2019] [Revised: 11/07/2019] [Accepted: 11/12/2019] [Indexed: 01/01/2023]
Abstract
Coloring is an important external quality of jujube fruit (Ziziphus jujuba Mill.), however during long-term storage, its commercial value degrades as the peel color and lustre significantly fade. Here, the gene expression and metabolite concentration were profiled in the fruit peel of jujube harvested at three ripening periods to elucidate the color formation mechanism. A strong accumulation of malvidin 3-O-glucoside and delphinidin 3-O-glucoside correlated with the reddening of jujube peel. At the onset of the fruit ripening, strong activities of the genes in the early steps of the flavonoid biosynthetic pathway were observed. During the last ripening periods, three UDP-glucose flavonoid 3-O-glucosyltransferase (UFGT) involved in the accumulation of anthocyanins were significantly increased and their proper manipulation could delay the peel reddening. This study sheds light on the metabolic pathways and candidate genes underlying the peel coloration in jujube and lays a foundation for the improvement of jujube fruit appeal during long-term storage.
Collapse
Affiliation(s)
- Qiong Zhang
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China; Shandong Institute of Pomology, Tai'an, Shandong 271000, China
| | - Lili Wang
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China
| | - Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China
| | - Zhihui Zhao
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China
| | - Jin Zhao
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China
| | - Zhongtang Wang
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China
| | - Guangfang Zhou
- Shandong Institute of Pomology, Tai'an, Shandong 271000, China
| | - Ping Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China.
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding 071001, China.
| |
Collapse
|
15
|
Li H, Gao W, Xue C, Zhang Y, Liu Z, Zhang Y, Meng X, Liu M, Zhao J. Genome-wide analysis of the bHLH gene family in Chinese jujube (Ziziphus jujuba Mill.) and wild jujube. BMC Genomics 2019; 20:568. [PMID: 31291886 PMCID: PMC6617894 DOI: 10.1186/s12864-019-5936-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [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: 03/06/2019] [Accepted: 06/26/2019] [Indexed: 12/24/2022] Open
Abstract
Background The bHLH (basic helix-loop-helix) transcription factor is one of the largest families of transcription factors in plants, containing a large number of members with diverse functions. Chinese jujube (Ziziphus jujuba Mill.) is the species with the highest economic value in the family Rhamnaceae. However, the characteristics of the bHLH family in the jujube genome are still unclear. Hence, ZjbHLHs were first searched at a genome-wide level, their expression levels under various conditions were investigated systematically, and their protein-protein interaction networks were predicted. Results We identified 92 ZjbHLHs in the jujube genome, and these genes were classified into 16 classes according to bHLH domains. Ten ZjbHLHs with atypical bHLH domains were found. Seventy ZjbHLHs were mapped to but not evenly distributed on 12 pseudo- chromosomes. The domain sequences among ZjbHLHs were highly conserved, and their conserved residues were also identified. The tissue-specific expression of 37 ZjbHLH genes in jujube and wild jujube showed diverse patterns, revealing that these genes likely perform multiple functions. Many ZjbHLH genes were screened and found to be involved in flower and fruit development, especially in earlier developmental stages. A few genes responsive to phytoplasma invasion were also verified. Based on protein-protein interaction prediction and homology comparison, protein-protein interaction networks composed of 92 ZjbHLHs were also established. Conclusions This study provides a comprehensive bioinformatics analysis of 92 identified ZjbHLH genes. We explored their expression patterns in various tissues, the flowering process, and fruit ripening and under phytoplasma stress. The protein-protein interaction networks of ZjbHLHs provide valuable clues toward further studies of their biological functions. Electronic supplementary material The online version of this article (10.1186/s12864-019-5936-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Hongtai Li
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Weilin Gao
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Yao Zhang
- College of Life Science, Hebei Agricultural University, Baoding, China.,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China
| | - Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Yu Zhang
- College of Forestry, Hebei Agricultural University, Baoding, China
| | - Xianwei Meng
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China. .,Hebei Key Laboratory of Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, China.
| |
Collapse
|
16
|
Xue C, Li H, Liu Z, Wang L, Zhao Y, Wei X, Fang H, Liu M, Zhao J. Genome-wide analysis of the WRKY gene family and their positive responses to phytoplasma invasion in Chinese jujube. BMC Genomics 2019; 20:464. [PMID: 31174470 PMCID: PMC6555936 DOI: 10.1186/s12864-019-5789-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [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: 01/28/2019] [Accepted: 05/09/2019] [Indexed: 11/20/2022] Open
Abstract
Background The WRKY gene family is one of the most important families in higher plants. As transcription factors, they actively respond to biotic and abiotic stress and are also involved in plant development. Chinese jujube (Ziziphus jujuba Mill.) is the largest type of dried fruit tree in China in terms of production, but its production is largely limited by phytoplasma infection, and the information about the role of WRKY genes under phytoplasma stress was still limited. Results We identified 54 ZjWRKYs in the jujube genome and classified them into three subgroups according to conserved WRKY domains and zinc-finger structure. 41 ZjWRKYs were distributed on 11 of 12 pseudo chromosomes in Chinese jujube. The majority of ZjWRKYs were highly expressed in the seven examined tissues, indicating that they play multiple roles in these vegetative and reproductive organs. Transcriptome data showed that most of the characterised ZjWRKYs were highly expressed at later stages of fruit development. RT-qPCR demonstrated that the expression of 23 ZjWRKYs changed following phytoplasma infection, suggesting that they are involved in signalling pathways that respond to phytoplasma stress. Then, STRING analysis and yeast two-hybrid screening proved that some ZjWRKY proteins were interacting with ZjMAPKK proteins, which were also involved in phytoplasma invasion. Moreover, their differential expressions were further confirmed in resistant and susceptible jujube varieties under phytoplasma stress. These results suggest that ZjWRKYs play significant roles in phytoplasma tolerance and should be crucial candidate genes for jujube-phytoplasma interaction. Conclusions 54 ZjWRKYs in Chinese jujube were identified and classified into three subgroups. 41 ZjWRKYs were unevenly distributed along the chromosomes. The majority of ZjWRKYs were highly expressed in various tissues. Most of the ZjWRKYs were positive responses to phytoplasma invasion, and that provided candidate genes for the future studies of jujube-phytoplasma interaction. Electronic supplementary material The online version of this article (10.1186/s12864-019-5789-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Chaoling Xue
- College of Life Science, Hebei Agricultural University, Baoding, China.,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China
| | - Hongtai Li
- College of Life Science, Hebei Agricultural University, Baoding, China.,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China
| | - Zhiguo Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Lili Wang
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China
| | - Yitong Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China
| | - Ximeng Wei
- College of Life Science, Hebei Agricultural University, Baoding, China
| | - Hu Fang
- BGI-Shenzhen, Shenzhen, China
| | - Mengjun Liu
- Research Center of Chinese Jujube, Hebei Agricultural University, Baoding, China.
| | - Jin Zhao
- College of Life Science, Hebei Agricultural University, Baoding, China. .,Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology, Hebei Agricultural University, Baoding, Hebei, China.
| |
Collapse
|
17
|
Hou L, Zhang Z, Dou S, Zhang Y, Pang X, Li Y. Genome-wide identification, characterization, and expression analysis of the expansin gene family in Chinese jujube (Ziziphus jujuba Mill.). Planta 2019; 249:815-829. [PMID: 30411169 DOI: 10.1007/s00425-018-3020-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [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: 08/29/2018] [Accepted: 09/23/2018] [Indexed: 05/10/2023]
Abstract
Main conclusion 30 expansin genes were identified in the jujube genome. Phylogenetic analysis classified expansins into 17 subgroups. Closely related expansins share a conserved gene structure. ZjEXPs had different expression patterns in different tissues. Plant-specific expansins were first discovered as pH-dependent cell-wall-loosening proteins involved in diverse physiological processes. No comprehensive analysis of the expansin gene family has yet been carried out at the whole genome level in Chinese jujube (Ziziphus jujuba Mill.). In this study, 30 expansin genes were identified in the jujube genome. These genes, which were distributed with varying densities across 10 of the 12 jujube chromosomes, could be divided into four subfamilies: 19 ZjEXPAs, 3 ZjEXPBs, 1 ZjEXLA, and 7 ZjEXLBs. Phylogenetic analysis of expansin genes in Arabidopsis, rice, apple, grape, and jujube classified these genes into 17 subgroups. Members of the same subfamily and subgroup shared conserved gene structure and motif compositions. Homology analysis identified 20 homologous gene pairs between jujube and Arabidopsis. Further analysis of ZjEXP gene promoter regions uncovered various growth, development and stress-responsive cis-acting elements. Expression analysis and transcript profiling revealed that ZjEXPs had different expression patterns in different tissues at various developmental stages. ZjEXPA4 and ZjEXPA6 were highly expressed in young fruits, ZjEXPA3 and ZjEXPA5 were significantly expressed in flowers, and ZjEXPA7 was specifically expressed in young leaves. The results of this study, the first systematic analysis of the jujube expansin gene family, can serve as a strong foundation for further elucidation of the physiological functions and biological roles of jujube expansin genes.
Collapse
Affiliation(s)
- Lu Hou
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Zhiyong Zhang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation and Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, School of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Suhan Dou
- Henan Longyuan Flowers &Trees Co., Ltd., Xuchang, 461000, China
| | - Yadong Zhang
- Henan Longyuan Flowers &Trees Co., Ltd., Xuchang, 461000, China
| | - Xiaoming Pang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yingyue Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China.
| |
Collapse
|
18
|
Qing J, Dawei W, Jun Z, Yulan X, Bingqi S, Fan Z. Genome-wide characterization and expression analyses of the MYB superfamily genes during developmental stages in Chinese jujube. PeerJ 2019; 7:e6353. [PMID: 30697496 PMCID: PMC6348095 DOI: 10.7717/peerj.6353] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 10/16/2018] [Accepted: 12/27/2018] [Indexed: 01/21/2023] Open
Abstract
The MYB transcription factor (TF) superfamily, one of the largest gene superfamilies, regulates a variety of physiological processes in plants. Although many MYB superfamily genes have been identified in plants, the MYB TFs in Chinese jujube (Ziziphus jujuba Mill.) have not been fully identified and characterized. Additionally, the functions of these genes remain unclear. In total, we identified 171 MYB superfamily genes in jujube and divided them into five subfamilies containing 99 genes of the R2R3-MYB subfamily, 58 genes of the MYB-related subfamily, four genes of the R1R2R3-MYB subfamily, one gene of the 4R-MYB subfamily, and nine genes of the atypical MYB subfamily. The 99 R2R3-MYB genes of jujube were divided into 35 groups, C1–C35, and the 58 MYB-related genes were divided into the following groups: the R-R-type, CCA1-like, I-box-binding-like, TBP-like, CPC-like, and Chinese jujube-specific groups. ZjMYB genes in jujube were well supported by additional highly conserved motifs and exon/intron structures. Most R1 repeats of MYB-related proteins comprised the R2 repeat and had highly conserved EED and EEE residue groups in jujube. Three tandem duplicated gene pairs were found on 12 chromosomes in jujube. According to an expression analysis of 126 ZjMYB genes, MYB-related genes played important roles in jujube development and fruit-related biological processes. The total flavonoid content of jujube fruit decreased as ripening progressed. A total of 93 expressed genes were identified in the RNA-sequencing data from jujube fruit, and 56 ZjMYB members presented significant correlations with total flavonoid contents by correlation analysis. Five pairs of paralogous MYB genes within jujube were composed of nine jujube MYB genes. A total of 14 ZjMYB genes had the same homology to the MYB genes of Arabidopsis and peach, indicating that these 14 MYB genes and their orthologs probably existed before the ancestral divergence of the MYB superfamily. We used a synteny analysis of MYB genes between jujube and Arabidopsis to predict that the functions of the ZjMYBs involve flavonoid/phenylpropanoid metabolism, the light signaling pathway, auxin signal transduction, and responses to various abiotic stresses (cold, drought, and salt stresses). Additionally, we speculate that ZjMYB108 is an important TF involved in the flavonoid metabolic pathway. This comprehensive analysis of MYB superfamily genes in jujube lay a solid foundation for future comprehensive analyses of ZjMYB gene functions.
Collapse
Affiliation(s)
- Ji Qing
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China
| | - Wang Dawei
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China
| | - Zhou Jun
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China.,North Minzu University, College of Life Science and Engineering, Yinchuan, China
| | - Xu Yulan
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China
| | - Shen Bingqi
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China
| | - Zhou Fan
- Southwest Forestry University, Key Laboratory for Forest Resource Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Kunming, Yunnan, China
| |
Collapse
|
19
|
Rahman E, Momin A, Zhao L, Guo X, Xu D, Zhou F, Ji B. Bioactive, nutritional composition, heavy metal and pesticide residue of four Chinese jujube cultivars. Food Sci Biotechnol 2018; 27:323-31. [PMID: 30263755 DOI: 10.1007/s10068-017-0256-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 10/01/2017] [Accepted: 11/09/2017] [Indexed: 12/12/2022] Open
Abstract
This study aims to conduct a detailed investigation on four cultivars grown in northwest China, concentrating on the analysis of the bioactive contents, nutrients, heavy metal concentrations, and pesticide residue contents. Those Chinese jujubes consist of 51.99-71.75% edible part, 82.35-89.63% carbohydrates, 4.43-6.01% protein, 0.48-0.63% lipid, 2.80-4.80% polysaccharide, 45.64-88.97 mg/100 g ascorbic acid, 132.16-196.58 mg/100 g phenolics and 101.17-132.04 mg/100 g flavonoids in dry matter. In those four Chinese jujube cultivars, sulfur amino acids are the first limiting amino acids for adults, and aromatic amino acids are for children. The amount of heavy metal and pesticide residue concentrations in those jujubes was way below the limit. All four cultivars were found to have different nutritional values except for the carbohydrates; they had higher rates of carbohydrates and polysaccharide than those previously reported ones from Eastern China; and they are a better source for carbohydrates, vitamin C and functional amino acids.
Collapse
|
20
|
Liu Z, Zhang L, Xue C, Fang H, Zhao J, Liu M. Genome-wide identification and analysis of MAPK and MAPKK gene family in Chinese jujube (Ziziphus jujuba Mill.). BMC Genomics 2017; 18:855. [PMID: 29121856 DOI: 10.1186/s12864-017-4259-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [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: 03/16/2017] [Accepted: 11/01/2017] [Indexed: 12/20/2022] Open
Abstract
Background Chinese jujube (Ziziphus jujuba Mill.) is one of the most important members in the Rhamnaceae family. The whole genome sequence and more than 30,000 proteins of Chinese jujube have been obtained in 2014. Mitogen-activated protein kinase cascades are universal signal transduction modules in plants, which is rapidly activated under various biotic and abiotic stresses. To date, there has been no comprehensive analysis of the MAPK and MAPKK gene family in Chinese jujube at the whole genome level. Results By performing a series of bioinformatics analysis, ten MAPK and five MAPKK genes were identified from the genome database of Chinese jujube, and then compared with the homologous genes from Arabidopsis. Phylogenetic analysis showed that ZjMAPKs was classified into four known groups, including A, B, C and D. ZjMAPKs contains five members of the TEY phosphorylation site and five members with the TDY motif. The ZjMAPKK family was subsequently divided into three groups, A, B and D. The gene structure, conserved motifs, functional annotation and chromosome distribution of ZjMAPKs and ZjMAPKKs were also predicted. ZjMAPKs and ZjMAPKKs were distributed on nine pseudo-chromosomes of Chinese jujube. Subsequently, expression analysis of ZjMAPK and ZjMAPKK genes using reverse transcription PCR and quantitative real-time PCR was carried out. The majority of ZjMAPK and ZjMAPKK genes were expressed in all tested organs/tissues with considerable differences in transcript levels indicating that they might be constitutively expressed. Moreover, ZjMKK5 was specific expressed in early development stage of jujube flower bud, indicating it plays some roles in reproductive organs development. The transcript expression of most ZjMAPK and ZjMAPKK genes was down-regulated in response to plant growth regulators, darkness treatment and phytoplasma infection. Conclusions We identified ten ZjMAPK and five ZjMAPKK genes from the genome database of Chinese jujube, the research results shown that ZjMPKs and ZjMKKs have the different expression patterns, indicating that they might play different roles in response to various treatments. The results provide valuable information for the further elucidation of physiological functions and biological roles of jujube MAPKs and MAPKKs. Electronic supplementary material The online version of this article (10.1186/s12864-017-4259-4) contains supplementary material, which is available to authorized users.
Collapse
|
21
|
Yu ZP, Xu DD, Lu LF, Zheng XD, Chen W. Immunomodulatory effect of a formula developed from American ginseng and Chinese jujube extracts in mice. J Zhejiang Univ Sci B 2016; 17:147-57. [PMID: 26834015 DOI: 10.1631/jzus.b1500170] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [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: 01/24/2023]
Abstract
BACKGROUND American ginseng (Panax quinquefolius L.) and Chinese jujube (Zizyphus jujuba Mill.) are commonly used in traditional Chinese medicine to enhance immune function. OBJECTIVE The present study aimed to develop one Chinese prescription, Shenzao Cha (SZC), consisting of American ginseng and Chinese jujube, and systematically investigate its immunomodulation in healthy ICR mice. METHODS Normal ICR mice received intragastric administration of SZC (1.3, 2.6, and 5.2 g raw material/kg body weight) once daily for four weeks, while a control group received the same amount of sterile water. RESULTS SZC significantly increased the spleen and thymus indices and T-lymphocyte proliferation, while the T-lymphocyte proliferation in the 5.2 g/kg group was 1.4-fold higher than that in the control. Further, 1.3 g/kg SZC could markedly improve hemolytic activity by 25.2%, and 2.6 g/kg SZC increased the NK cell activity by 78.6% relative to the control. In addition, the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), that participated in modulating oxidative stress, were significantly increased in the liver, spleen, thymus, and serum, while the contents of malondialdehyde were dramatically decreased. CONCLUSIONS SZC exhibited potent immunomodulatory effects on innate and adaptive immunity in healthy ICR mice, as well as potential antioxidant activity for prevention of oxidative stress, which was suggested to partly contribute to the immune enhancement.
Collapse
Affiliation(s)
- Zhuo-ping Yu
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Dong-dong Xu
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Lai-feng Lu
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Xiao-dong Zheng
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| | - Wei Chen
- College of Biosystems Engineering and Food Science, Fuli Institute of Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang R&D Center for Food Technology and Equipment, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
22
|
Liu Z, Zhao J, Liu M. Photosynthetic responses to phytoplasma infection in Chinese jujube. Plant Physiol Biochem 2016; 105:12-20. [PMID: 27064193 DOI: 10.1016/j.plaphy.2016.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [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: 01/25/2016] [Revised: 03/24/2016] [Accepted: 04/02/2016] [Indexed: 06/05/2023]
Abstract
Phytoplasma is one of the most devastating plant pathogens. Jujube witches' broom (JWB) is a typical and highly fatal phytoplasma disease of Chinese jujube (Ziziphus jujuba Mill.), which is widely cultivated in Asia. To further elucidate the mechanism of plant-phytoplasma interaction, we first compared the effects of phytoplasma infection on photosynthetic pigments and activities between a JWB-resistant cultivar (Xingguang) and a susceptible cultivar (Pozao). Total chlorophyll and carotenoid levels were significantly decreased in the susceptible cultivar at later stages of infection, but were remarkably increased in the resistant cultivar at the earlier stages. Compared to uninfected plant, a significant decrease in the main photochemical parameters (Fv/Fm, ΦPSII and qP) was recorded at the initial stages of infection in the resistant cultivar, but occurred at later stages in the susceptible cultivar. Meanwhile, the qRT-PCR results of four key photosynthesis-related genes (ZjGluTR, ZjCBP, ZjRubisco and ZjRCA2) demonstrated that the expression patterns were similar in uninfected cultivars, but up-regulated in resistant cultivar and down-regulated in the susceptible one at 12 wks after grafting inoculation. Collectively, our data indicated that the resistant cultivar 'Xingguang' undergoes a decrease in initial stage (inhibiting phytoplasma multiplication) and then a rapid enhancement of photosynthetic activity (helping jujube recovery) in response to phytoplasma infection, while the susceptible cultivar 'Pozao' displays a later decrease in photosynthetic activity. The novel photosynthetic response pattern of the resistant cultivar may contribute to its stronger immunity to phytoplasma infection, which provides new insights into plant-phytoplasma interactions.
Collapse
Affiliation(s)
- Zhiguo Liu
- Research Center of Chinese Jujube, Agricultural University of Hebei, Baoding, 071001, China
| | - Jin Zhao
- College of Life Science, Agricultural University of Hebei, Baoding, 071000, China.
| | - Mengjun Liu
- Research Center of Chinese Jujube, Agricultural University of Hebei, Baoding, 071001, China.
| |
Collapse
|