中国农业科学2025，Vol.58Issue(8)：1604-1616,13.DOI:10.3864/j.issn.0578-1752.2025.08.011
辣椒MADS-box 转录因子基因CaAGL61的耐热功能分析
Functional Analysis of MADS-box Transcription Factor Gene CaAGL61 in Heat Tolerance of Pepper
摘要
Abstract
[Objective]MADS-box transcription factors are one of the largest transcription factor families in plants,and play important roles in plant growth,development,and stress responses.Previously,based on transcriptome data of pepper,a heat-responsive gene,Agamous-like MADS-box protein61(AGL61),was identified as a MADS-box transcription factor.However,the function of CaAGL61 in pepper heat stress remains unknown.In this study,we explored the molecular function of CaAGL61 in heat tolerance of pepper plants,providing the regulatory insights of CaAGL61 as a potential locus for genetic improvement.[Method]The SMART online tool was used to predict the conserved domain of CaAGL61,and a phylogenetic tree of AGL61 in pepper and other plant species was constructed using MEGA7.The expression pattern of CaAGL61 was analyzed by quantitative real-time PCR.The subcellular localization of CaAGL61 was examined in tobacco,and its transcriptional regulatory role was investigated using a yeast two-hybrid system(Y2H).The effects of CaAGL61 on heat tolerance of pepper were accessed using transgenic plants generated by virus-induced gene silencing(VIGS)and transient overexpression techniques.[Result]CaAGL61 encodes a protein of 179 amino acids,containing a MADS domain and exhibiting high evolutionary conservation.CaAGL61's expressional level was relatively high in the flower of pepper,followed by the stem and fruit,and lowest in the root.Further analysis reveals that the expression of CaAGL61 increased along with flower maturation process,peaking in the anther during pollination and fruit setting.High temperature treatment at 45℃significantly upregulates the expression of CaAGL61.Subcellular localization showed that CaAGL61 is located in the nucleus,and yeast transcriptional activation assays indicates that CaAGL61 has transcriptional activation activity.Silencing of CaAGL61 significantly enhances heat tolerance of pepper.Comparing with control,CaAGL61-silenced plants exhibit reduced wilting in plant growth points,lower relative electrolyte leakage,reduced content of malondialdehyde,and accumulation of dead cells and reactive oxygen species(ROS),and increased content of chlorophyll under heat stress.However,transient overexpression of CaAGL61 reduces the heat tolerance of pepper,indicated by more severe heat-stress damage,higher relative electrolyte leakage,increased content of malondialdehyde,and accumulation of dead cells and ROS,and decreased content of chlorophyll compared to control.[Conclusion]A heat-responsive MADS-box transcription factor gene,CaAGL61,was identified in pepper.This gene negatively regulates pepper heat tolerance by exacerbating oxidative stress.关键词
辣椒/耐热/MADS-box转录因子/CaAGL61/负调控Key words
pepper/heat tolerance/MADS-box transcription factor/CaAGL61/negative regulation引用本文复制引用
王梦园,魏倩睿,李海艳,杨巧敏,宇军,黄炜,逯明辉..辣椒MADS-box 转录因子基因CaAGL61的耐热功能分析[J].中国农业科学,2025,58(8):1604-1616,13.基金项目
国家自然科学基金(32172552)、国家大宗蔬菜产业技术体系专项(CARS-23-G22)、陕西省农业核心技术攻关项目(2024NYGG008-2)、西安市科技计划(22NYYF007) （32172552）
