title: Pepper CabZIP63 acts as a positive regulator during Ralstonia solanacearum or high temperature-high humidity challenge in a positive feedback loop with CaWRKY40.
abstract: CaWRKY40 is known to act as a positive regulator in the response of pepper (Capsicum annuum) to Ralstonia solanacearum inoculation (RSI) or high temperature-high humidity (HTHH), but the underlying mechanism remains elusive. Herein, we report that CabZIP63, a pepper bZIP family member, participates in this process by regulating the expression of CaWRKY40. CabZIP63 was found to localize in the nuclei, be up-regulated by RSI or HTHH, bind to promoters of both CabZIP63(pCabZIP63) and CaWRKY40(pCaWRKY40), and activate pCabZIP63- and pCaWRKY40-driven β-glucuronidase expression in a C- or G-box-dependent manner. Silencing of CabZIP63 by virus-induced gene silencing (VIGS) in pepper plants significantly attenuated their resistance to RSI and tolerance to HTHH, accompanied by down-regulation of immunity- or thermotolerance-associated CaPR1, CaNPR1, CaDEF1, and CaHSP24. Hypersensitive response-mediated cell death and expression of the tested immunity- and thermotolerance-associated marker genes were induced by transient overexpression (TOE) of CabZIP63, but decreased by that of CabZIP63-SRDX. Additionally, binding of CabZIP63 to pCaWRKY40 was up-regulated by RSI or HTHH, and the transcript level of CaWRKY40 and binding of CaWRKY40 to the promoters of CaPR1, CaNPR1, CaDEF1 and CaHSP24 were up-regulated by TOE of CabZIP63. On the other hand, CabZIP63 was also up-regulated transcriptionally by TOE of CaWRKY40. The data suggest collectively that CabZIP63 directly or indirectly regulates the expression of CaWRKY40 at both the transcriptional and post-transcriptional level, forming a positive feedback loop with CaWRKY40 during pepper's response to RSI or HTHH. Altogether, our data will help to elucidate the underlying mechanism of crosstalk between pepper's response to RSI and HTHH.
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Shen
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Zhiqin
authors.initials: Z
authors.lastname: Liu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Yang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Tong
authors.initials: T
authors.lastname: Yang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Liang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Jiayu
authors.initials: J
authors.lastname: Wen
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Jiazhi
authors.initials: J
authors.lastname: Li
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Lanping
authors.initials: L
authors.lastname: Shi
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Tang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Jiong
authors.initials: J
authors.lastname: Hu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Cailing
authors.initials: C
authors.lastname: Liu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Yangwen
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Lin
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Rongzhang
authors.initials: R
authors.lastname: Wang
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Huanxin
authors.initials: H
authors.lastname: Yu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Shaoliang
authors.initials: S
authors.lastname: Mou
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Ansar
authors.initials: A
authors.lastname: Hussain
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Hanyang
authors.initials: H
authors.lastname: Cai
authors.affiliation: College of Life Science, Jinggang Shan University, Ji'an, Jiangxi 343000, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: He
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China.
authors.forename: Deyi
authors.initials: D
authors.lastname: Guan
authors.affiliation: College of Life Science, Jinggang Shan University, Ji'an, Jiangxi 343000, PR China shlhe201304@aliyun.com.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wu
authors.affiliation: National Education Minister, Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, PR China shlhe201304@aliyun.com.
authors.forename: Shuilin
authors.initials: S
authors.lastname: He
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000085:Acetates / Q000494:pharmacology; D000222:Adaptation, Physiological / Q000187:drug effects; D001483:Base Sequence; D015415:Biomarkers / Q000378:metabolism; D002212:Capsicum / Q000187:drug effects / Q000235:genetics / Q000276:immunology / Q000382:microbiology*; D016923:Cell Death / Q000187:drug effects; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology; D005030:Ethylenes / Q000494:pharmacology; D025461:Feedback, Physiological / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020868:Gene Silencing / Q000187:drug effects; D017343:Genes, Plant; D006358:Hot Temperature; D006813:Humidity; D054883:Oxylipins / Q000494:pharmacology; D057865:Plant Immunity / Q000187:drug effects; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D043368:Ralstonia solanacearum / Q000502:physiology*; D020539:Sequence Analysis, Protein; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D000085:Acetates; D015415:Biomarkers; D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D010940:Plant Proteins; D000040:Abscisic Acid; C072239:methyl jasmonate
keywords: CaWRKY40; CabZIP63; Ralstonia solanacearum; high temperature–high humidity; pepper; transcription factors.