CsLAC4,regulated by CsmiR397a,confers drought tolerance to the tea plant by enhancing lignin biosynthesis  

作　　者：Hongbin Yang Linxuan Xia Jingshan Li Xiaoyu Jia Xinyue Jia Yuying Qi Youben Yu Weidong Wang 

机构地区：[1]College of Horticulture,Northwest A&F University,Yangling,Shaanxi 712100,China

出　　处：《Stress Biology》2024年第1期39-51,共13页逆境生物学(英文)

基　　金：supported by the National Key Research and Development Program of China(2022YFD1602003);the Key Research and Development Program of Shaanxi(2024NC-ZDCYL-04-07);Natural Science Basic Research Program of Shaanxi(2021JQ-162);the National Natural Science Foundation of China(No.31902071);the China Agricultural Research System of Ministry of Finance and Ministry of Agriculture and Rural Affairs(CARS-19).

摘　　要：Drought is a prevalent abiotic stress that commonly affects the quality and yield of tea.Although numerous studies have shown that lignin accumulation holds significant importance in conferring drought tolerance to tea plants,the underlying molecular regulatory mechanisms governing the tea plant’s response to drought remain largely elusive.LACCASEs(LACs),which belong to the class of plant copper-containing polyphenol oxidases,have been widely reported to participate in lignin biosynthesis in plants and are implicated in numerous plant life processes,especially in the context of adverse conditions.In this study,we detected the upregulation of CsLAC4 in response to drought induction.Remarkably,the overexpression of CsLAC4 not only substantially increased the lignin content of transgenic Arabidopsis thaliana but also simulated the development of vascular tissues,consequently leading to a significant enhancement in drought tolerance.Moreover,via dual-luciferase assays and transient overexpression in tea leaves,we revealed that CsLAC4 was negatively regulated by the upstream CsmiR397a.Interestingly,the expression of CsmiR397a was downregulated during drought stress in tea plants.Arabidopsis thaliana overexpressing CsmiR397a showed increased sensitivity to drought stress.By transient overexpression of CsmiR397a and CsLAC4 in tea plant leaves,we verified that CsLAC4,which is regulated by CsmiR397a,conferred drought tolerance to tea plants by enhancing lignin biosynthesis.These findings enhance our understanding of the molecular regulatory mechanisms underlying the response of tea plants to drought stress.

关 键 词：Tea plant DROUGHT LACCASE MICRORNA Lignin biosynthesis 

分 类 号：Q94[生物学—植物学]