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Samayoa LF, Cao A, Santiago R, Malvar RA, Butrón A. Genome-wide association analysis for fumonisin content in maize kernels. BMC Plant Biol 2019; 19:166. [PMID: 31029090 PMCID: PMC6486958 DOI: 10.1186/s12870-019-1759-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/04/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Plant breeding has been proposed as one of the most effective and environmentally safe methods to control fungal infection and to reduce fumonisin accumulation. However, conventional breeding can be hampered by the complex genetic architecture of resistance to fumonisin accumulation and marker-assisted selection is proposed as an efficient alternative. In the current study, GWAS has been performed for the first time for detecting high-resolution QTL for resistance to fumonisin accumulation in maize kernels complementing published GWAS results for Fusarium ear rot. RESULTS Thirty-nine SNPs significantly associated with resistance to fumonisin accumulation in maize kernels were found and clustered into 17 QTL. Novel QTLs for fumonisin content would be at bins 3.02, 5.02, 7.05 and 8.07. Genes with annotated functions probably implicated in resistance to pathogens based on previous studies have been highlighted. CONCLUSIONS Breeding approaches to fix favorable functional variants for genes implicated in maize immune response signaling may be especially useful to reduce kernel contamination with fumonisins without significantly interfering in mycelia development and growth and, consequently, in the beneficial endophytic behavior of Fusarium verticillioides.
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Affiliation(s)
- L. F. Samayoa
- Misión Biológica de Galicia (MBG - CSIC), Box 28, 36080 Pontevedra, Spain
- Present address at department of Crop Science, North Carolina State University, Raleigh, NC 27695 USA
| | - A. Cao
- Misión Biológica de Galicia (MBG - CSIC), Box 28, 36080 Pontevedra, Spain
- Facultad de Biología, Department Biología Vegetal y Ciencias del Suelo, Universidad de Vigo, As Lagoas Marcosende, 36310 Vigo, Spain
- Agrobiología Ambiental, Calidad de Suelos y Plantas (BVE1-UVIGO), Unidad Asociada a la MBG – CSIC, 36143 Pontevedra, Spain
| | - R. Santiago
- Facultad de Biología, Department Biología Vegetal y Ciencias del Suelo, Universidad de Vigo, As Lagoas Marcosende, 36310 Vigo, Spain
- Agrobiología Ambiental, Calidad de Suelos y Plantas (BVE1-UVIGO), Unidad Asociada a la MBG – CSIC, 36143 Pontevedra, Spain
| | - R. A. Malvar
- Misión Biológica de Galicia (MBG - CSIC), Box 28, 36080 Pontevedra, Spain
- Agrobiología Ambiental, Calidad de Suelos y Plantas (BVE1-UVIGO), Unidad Asociada a la MBG – CSIC, 36143 Pontevedra, Spain
| | - A. Butrón
- Misión Biológica de Galicia (MBG - CSIC), Box 28, 36080 Pontevedra, Spain
- Agrobiología Ambiental, Calidad de Suelos y Plantas (BVE1-UVIGO), Unidad Asociada a la MBG – CSIC, 36143 Pontevedra, Spain
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Lee DK, Min YS, Yoo SS, Shim HS, Park SY, Sohn UD. Effect of Sphingosine-1-Phosphate on Intracellular Free Ca²⁺ in Cat Esophageal Smooth Muscle Cells. Biomol Ther (Seoul) 2018; 26:546-552. [PMID: 29915165 PMCID: PMC6254643 DOI: 10.4062/biomolther.2018.053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 03/22/2018] [Revised: 05/04/2018] [Accepted: 05/08/2018] [Indexed: 12/31/2022] Open
Abstract
A comprehensive collection of proteins senses local changes in intracellular Ca²⁺ concentrations ([Ca²⁺]i) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular Ca²⁺ concentrations in cat esophageal smooth muscle cells. To measure [Ca²⁺]i levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in [Ca²⁺]i in the cells. Pretreatment with EGTA, an extracellular Ca²⁺ chelator, decreased the S1P-induced increase in [Ca²⁺]i, and an L-type Ca²⁺-channel blocker, nimodipine, decreased the effect of S1P. This indicates that Ca²⁺ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an InsP3 receptor blocker, the S1P-evoked increase in [Ca²⁺]i was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of Gi-protein, suppressed the increase in [Ca²⁺]i evoked by S1P. These results suggest that the S1P-induced increase in [Ca²⁺]i in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of Ca²⁺ from the InsP3-sensitive Ca²⁺ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular Ca²⁺ via the L type Ca²⁺ channel, which was dependent on activation of the S1P4 receptor coupled to PTX-sensitive Gi protein, via phospholipase C-mediated Ca²⁺ release from the InsP3-sensitive Ca²⁺ pool in cat esophageal smooth muscle cells.
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Affiliation(s)
- Dong Kyu Lee
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06911, Republic of Korea
| | - Young Sil Min
- Department of Pharmaceutical Engineering, College of Convergence Science and Technology, Jung Won University, Goesan 28054, Republic of Korea
| | - Seong Su Yoo
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06911, Republic of Korea
| | - Hyun Sub Shim
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06911, Republic of Korea
| | - Sun Young Park
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06911, Republic of Korea
| | - Uy Dong Sohn
- Department of Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06911, Republic of Korea
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Zhong L, Liu E, Yang C, Diao Y, Harijati N, Liu J, Hu Z, Jin S. Gene cloning of a neutral ceramidase from the sphingolipid metabolic pathway based on transcriptome analysis of Amorphophallus muelleri. PLoS One 2018; 13:e0194863. [PMID: 29590184 PMCID: PMC5874051 DOI: 10.1371/journal.pone.0194863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/12/2018] [Indexed: 01/10/2023] Open
Abstract
Amorphophallus is a perennial herbaceous plant species mainly distributed in the tropics or subtropics of Asia and Africa. It has been used as a traditional medicine for a long time and now is utilized for the pharmaceutical, chemical and agriculture industries as a valued economic crop. Recently, Amorphophallus has attracted tremendous interest because of its high ceramide content. However, the breeding and genome studies are severely limited by the arduous whole genome sequencing of Amorphophallus. In this study, the transcriptome data of A. muelleri was obtained by utilizing the high-throughput Illumina sequencing platform. Based on this information, the majority of the significant genes involved in the proposed sphingolipid metabolic pathway were identified. Then, the full-length neutral ceramidase cDNA was obtained with the help of its candidate transcripts, which were acquired from the transcriptome data. Furthermore, we demonstrated that this neutral ceramidase was a real ceramidase by eukaryotic expression in the yeast double knockout mutant Δypc1 Δydc1, which lacks the ceramidases—dihydroCDase (YDC1p), phytoCDase (YPC1p). In addition, the biochemical characterization of purified A. muelleri ceramidase (AmCDase) exhibited classical Michaelis-Menten kinetics with an optimal activity ranging from pH 6.5 to 8.0. Based on our knowledge, this study is the first to report the related information of the neutral ceramidase in Amorphophallus. All datasets can provide significant information for related studies, such as gene expression, genetic improvement and application on breeding in Amorphophallus.
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Affiliation(s)
- Lin Zhong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Erxi Liu
- Institute of Konjac, Enshi Academy of Agricultural Sciences, Enshi, Hubei, PR China
| | - Chaozhu Yang
- Institute of Konjac, Enshi Academy of Agricultural Sciences, Enshi, Hubei, PR China
| | - Ying Diao
- Lotus Engineering Research Center of Hubei Province, College of Life Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Nunung Harijati
- Department of Biology, Faculty of Mathematics and Natural Sciences, Brawijaya University, Jl.Veteran Malang, Indonesia
| | - Jiangdong Liu
- College of Life Science, Department of Biology, College of Life Sciences, Wuhan University, Wuhan, Hubei, PR China
| | - Zhongli Hu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, Hubei, PR China
- * E-mail: (ZH); (SJ)
| | - Surong Jin
- Institute of Chemical and Life Science, Wuhan University of Technology, Wuhan, Hubei, PR China
- * E-mail: (ZH); (SJ)
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Shi XX, Huang YJ, Begum MA, Zhu MF, Li FQ, Zhang MJ, Zhou WW, Mao C, Zhu ZR. A neutral ceramidase, NlnCDase, is involved in the stress responses of brown planthopper, Nilaparvata lugens (Stål). Sci Rep 2018; 8:1130. [PMID: 29348442 DOI: 10.1038/s41598-018-19219-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 11/27/2017] [Indexed: 12/27/2022] Open
Abstract
Ceramidases (CDases) are vital enzymes involved in the biosynthesis of sphingolipids, which are essential components of eukaryotic membranes. The function of these enzymes in insects, however, is poorly understood. We identified a neutral ceramidase (NlnCDase) from the brown planthopper, Nilaparvata lugens, one of the most destructive hemipteran pests of rice. The C12-ceramide was the most preferred substrate for the NlnCDase enzyme. The activity of the NlnCDase enzyme was highest in the neutral-pH range (pH 6.0). It was inhibited by EGTA, Cs+ and Fe2+, while stimulated by EDTA and Ca2+. Moreover, the NlnCDase has higher transcript level and activity in adults than in eggs and nymphs, and in the reproductive organs (ovaries and spermaries) than in other tissues (i.e. heads, thorax, legs, midguts), which suggested that the NlnCDase might be elevated to mediate developmental process. In addition, transcripts and activity of the NlnCDase were up-regulated under abiotic stresses including starvation, abnormal temperature, and insecticides, and biotic stress of resistant rice varieties. Knocking down NlnCDase by RNA interference increased female survival under starvation and temperature stresses, suggesting that NlnCDase might be involved in the stress response in N. lugens.
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Jiao WJ, Li FQ, Bai YL, Shi XX, Zhu MF, Zhang MJ, Mao CG, Zhu ZR. Rice Stripe Virus Infection Alters mRNA Levels of Sphingolipid-Metabolizing Enzymes and Sphingolipids Content in Laodelphax striatellus. J Insect Sci 2017; 17:iew111. [PMID: 28130458 PMCID: PMC5270407 DOI: 10.1093/jisesa/iew111] [Citation(s) in RCA: 2] [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: 10/03/2016] [Indexed: 05/05/2023]
Abstract
Sphingolipids and their metabolites have been implicated in viral infection and replication in mammal cells but how their metabolizing enzymes in the host are regulated by viruses remains largely unknown. Here we report the identification of 12 sphingolipid genes and their regulation by Rice stripe virus in the small brown planthopper (Laodelphax striatellus Fallén), a serious pest of rice throughout eastern Asia. According to protein sequence similarity, we identified 12 sphingolipid enzyme genes in L. striatellus. By comparing their mRNA levels in viruliferous versus nonviruliferous L. striatellus at different life stages by qPCR, we found that RSV infection upregulated six genes (LsCGT1, LsNAGA1, LsSGPP, LsSMPD4, LsSMS, and LsSPT) in most stages of L. striatellus Especially, four genes (LsCGT1, LsSMPD2, LsNAGA1, and LsSMS) and another three genes (LsNAGA1, LsSGPP, and LsSMS) were significantly upregulated in viruliferous third-instar and fourth-instar nymphs, respectively. HPLC-MS/MS results showed that RSV infection increased the levels of various ceramides, such as Cer18:0, Cer20:0, and Cer22:0 species, in third and fourth instar L. striatellus nymphs. Together, these results demonstrate that RSV infection alters the transcript levels of various sphingolipid enzymes and the contents of sphingolipids in L. striatellus, indicating that sphingolipids may be important for RSV infection or replication in L. striatellus.
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Affiliation(s)
- Wen-Juan Jiao
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Fei-Qiang Li
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yue-Liang Bai
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiao-Xiao Shi
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Mu-Fei Zhu
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Min-Jing Zhang
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Cun-Gui Mao
- Department of Medicine, State University of New York at Stony Brook, Stony Brook, NY, USA
| | - Zeng-Rong Zhu
- State Key Laboratory of Rice Biology/Key Laboratory of Agricultural Entomology Ministry of Agriculture/Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
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Wu JX, Li J, Liu Z, Yin J, Chang ZY, Rong C, Wu JL, Bi FC, Yao N. The Arabidopsis ceramidase AtACER functions in disease resistance and salt tolerance. Plant J 2015; 81:767-80. [PMID: 25619405 DOI: 10.1111/tpj.12769] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [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: 10/09/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 05/20/2023]
Abstract
Ceramidases hydrolyze ceramide into sphingosine and fatty acids. In mammals, ceramidases function as key regulators of sphingolipid homeostasis, but little is known about their roles in plants. Here we characterize the Arabidopsis ceramidase AtACER, a homolog of human alkaline ceramidases. The acer-1 T-DNA insertion mutant has pleiotropic phenotypes, including reduction of leaf size, dwarfing and an irregular wax layer, compared with wild-type plants. Quantitative sphingolipid profiling showed that acer-1 mutants and the artificial microRNA-mediated silenced line amiR-ACER-1 have high ceramide levels and decreased long chain bases. AtACER localizes predominantly to the endoplasmic reticulum, and partially to the Golgi complex. Furthermore, we found that acer-1 mutants and AtACER RNAi lines showed increased sensitivity to salt stress, and lines overexpressing AtACER showed increased tolerance to salt stress. Reduction of AtACER also increased plant susceptibility to Pseudomonas syringae. Our data highlight the key biological functions of ceramidases in biotic and abiotic stresses in plants.
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Affiliation(s)
- Jian-Xin Wu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
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Li J, Bi FC, Yin J, Wu JX, Rong C, Wu JL, Yao N. An Arabidopsis neutral ceramidase mutant ncer1 accumulates hydroxyceramides and is sensitive to oxidative stress. Front Plant Sci 2015; 6:460. [PMID: 26150824 PMCID: PMC4473688 DOI: 10.3389/fpls.2015.00460] [Citation(s) in RCA: 18] [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] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 06/08/2015] [Indexed: 05/18/2023]
Abstract
Ceramidases hydrolyze ceramide into sphingosine and fatty acids and, although ceramidases function as key regulators of sphingolipid homeostasis in mammals, their roles in plants remain largely unknown. Here, we characterized the Arabidopsis thaliana ceramidase AtNCER1, a homolog of human neutral ceramidase. AtNCER1 localizes predominantly on the endoplasmic reticulum. The ncer1 T-DNA insertion mutants had no visible phenotype, but accumulated hydroxyceramides, and showed increased sensitivity to oxidative stress induced by methyl viologen. Plants over-expressing AtNCER1 showed increased tolerance to oxidative stress. These data indicate that the Arabidopsis neutral ceramidase affects sphingolipid homeostasis and oxidative stress responses.
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Affiliation(s)
- Jian Li
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
| | - Fang-Cheng Bi
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
- Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, GuangzhouChina
| | - Jian Yin
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
| | - Jian-Xin Wu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
| | - Chan Rong
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
| | - Jia-Li Wu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
| | - Nan Yao
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, GuangzhouChina
- *Correspondence: Nan Yao, State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China,
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Ito M, Okino N, Tani M. New insight into the structure, reaction mechanism, and biological functions of neutral ceramidase. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:682-91. [PMID: 24064302 DOI: 10.1016/j.bbalip.2013.09.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [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: 06/21/2013] [Revised: 09/08/2013] [Accepted: 09/16/2013] [Indexed: 12/27/2022]
Abstract
Ceramidase (CDase) is an enzyme that hydrolyzes the N-acyl linkage between the sphingoid base and fatty acid of ceramide. These enzymes are classified into three distinct groups, acid (Asah1), neutral (Asah2), and alkaline (Asah3) CDases, based on their primary structure and optimum pH. Acid CDase catabolizes ceramide in lysosomes and is found only in vertebrates. In contrast, the distribution of neutral and alkaline CDases is broad, with both being found in species ranging from lower eukaryotes to mammals; however, only neutral CDase is found in prokaryotes, including some pathogenic bacteria. Neutral CDase is thought to have gained a specific domain (mucin box) in the N-terminal region after the vertebrate split, allowing the enzyme to be stably expressed at the plasma membrane as a type II membrane protein. The X-ray crystal structure of neutral CDase was recently solved, uncovering a unique structure and reaction mechanism for the enzyme. Neutral CDase contains a zinc ion in the active site that functions as a catalytic center, and the hydrolysis of the N-acyl linkage in ceramide proceeds through a mechanism that is similar to that described for zinc-dependent carboxypeptidase. This review describes the structure, reaction mechanism, and biological functions of neutral CDase in association with the molecular evolution, topology, and mechanical conformation. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology.
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Affiliation(s)
- Makoto Ito
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
| | - Nozomu Okino
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
| | - Motohiro Tani
- Department of Chemistry, Faculty of Science, Kyushu University, 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
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Zhou Y, Lin XW, Zhang YR, Huang YJ, Zhang CH, Yang Q, Li HY, Yuan JQ, Cheng JA, Xu R, Mao C, Zhu ZR. Identification and biochemical characterization of Laodelphax striatellus neutral ceramidase. Insect Mol Biol 2013; 22:366-75. [PMID: 23601004 PMCID: PMC3879266 DOI: 10.1111/imb.12028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Ceramidases are a group of enzymes that catalyse hydrolysis of ceramides to generate fatty acid and sphingosine. In this study, we report the cloning and characterization of the rice small brown planthopper Laodelphax striatellus neutral ceramidase (nCDase), LsnCer. LsnCer was identified by sequencing the transcriptome of L. striatellus and is a protein of 717 amino acids with a predicted molecular weight of 79.3 kDa. Similarly to other known nCDases, the optimum pH for LsnCer is 8.0 and the optimum temperature is 37 °C for its in vitro activity. LsnCer activity is inhibited by Zn(2+) significantly and Fe(2+) slightly. LsnCer has broad substrate specificity with a preference for ceramides with a medium acyl-chain or a monounsaturated long acyl-chain. Infection with rice strip virus (RSV) or treatment with insecticides significantly increased LsnCer mRNA expression and its enzymatic activity in L. striatellus. These results suggest that LsnCer is a bona fide nCDase that may have a role in adaption of L. striatellus to environmental stresses.
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Affiliation(s)
- Y Zhou
- State Key Laboratory of Rice Biology, Key laboratory of Agricultural Entomology, the Ministry of Agriculture of China, Hangzhou, Zhejiang, China
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Zhang H, Li L, Yu Y, Mo J, Sun L, Liu B, Li D, Song F. Cloning and characterization of two rice long-chain base kinase genes and their function in disease resistance and cell death. Mol Biol Rep 2012; 40:117-27. [PMID: 23054004 DOI: 10.1007/s11033-012-2040-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 10/02/2012] [Indexed: 10/27/2022]
Abstract
Sphingolipid metabolites such as long-chain base 1-phosphates (LCBPs) have been shown to play an important role in plants; however, little is known about their function in plant disease resistance and programmed cell death (PCD). In the present study, we cloned and identified two rice long-chain base kinase (LCBK) genes (OsLCBK1 and OsLCBK2), which are involved in biosynthesis of LCBPs, and performed functional analysis in transgenic tobacco. Expression of OsLCBK1 and OsLCBK2 was induced in rice seedlings after treatments with defense signaling molecules and after infection by Magnaporthe grisea, the causal agent of blast disease. Transgenic tobacco plants overexpressing OsLCBK1 were generated and disease resistance assays indicate that the OsLCBK1-overexpressing plants showed enhanced disease resistance against Pseudmonas syringae pv. tabacci, the causal agent of wildfire disease, and tobacco mosaic virus. Expression levels of some defense-related genes were constitutively up-regulated and further induced after pathogen infection in the OsLCBK1-overexpressing plants. Treatment with fungal toxin fumonisin B1, an effective inducer of PCD in plants, resulted in reduced level of cell death in the OsLCBK1-overexpressing plants, as indicated by cell death staining, leakage of electrolyte and expression of hypersensitive response indicator genes. These data suggest that rice LCBKs, probably through regulation of endogenous LCBP level, play important roles in disease resistance response and PCD in plants.
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Affiliation(s)
- Huijuan Zhang
- State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, Zhejiang, People's Republic of China
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