中国农业科学2025，Vol.58Issue(8)：1617-1629,13.DOI:10.3864/j.issn.0578-1752.2025.08.012
菊花CmASMT的克隆及其在高温抗性中的作用
Cloning of CmASMT and Its Role in Thermotolerance of Chrysanthemum
摘要
Abstract
[Background]Chrysanthemum is one of the ten Chinese traditional flowers and four most important cut flowers in the world,originating from China and widely cultivated throughout the world.As chrysanthemum thrives in mild and cool climates,the summer high-temperature weather leads to continuous high temperature in protected cultivation environments,which seriously affects the yield and quality of chrysanthemum.[Objective]Exogenous application of melatonin helps to regulate plant response to various abiotic stresses,including high-temperature stress.N-acetyl-5-hydroxytryptamine methyltransferase(ASMT)is the rate-limiting enzyme for melatonin biosynthesis.This study investigated the function of CmASMT,examined its effect on chrysanthemum growth under high-temperature stress,and explored how endogenous melatonin synthesis influences thermotolerance.This paper provides a theoretical basis for the molecular mechanism of melatonin-regulated thermotolerance in plants and the molecular breeding of chrysanthemum.[Method]The CmASMT involved in melatonin biosynthesis was cloned from Chrysanthemum morifolium Jinba and analyzed for bioinformatics,subcellular localization,and spatiotemporal expression properties.CmASMT gene-silenced plants were generated by using virus-induced gene silencing(VIGS)technology to investigate the effects of CmASMT on heat tolerance of chrysanthemum through photosynthesis,the stability of the membrane system,and antioxidant system.[Result]The ORF of CmASMT is 1 059 bp in length,encodes 352 amino acids,and belongs to the O-methyltransferases family.During the vegetative growth stage,CmASMT is expressed in roots,stems,leaves and buds of chrysanthemum,with the highest levels observe in the roots.Expression of CmASMT was induced by high temperature,low temperature,waterlogging,salt and drought stress,and CmASMT was most responsive to high-temperature stress.The CmASMT protein localized to the cell membranes,cytoplasm and nucleus.The content of endogenous melatonin in CmASMT-silenced plants of chrysanthemum was significantly reduced.Under high-temperature stress,CmASMT-silenced plants exhibited inhibition of photosynthesis,reduction of membrane system stability,aggravation of oxidative stress,weakening of antioxidant enzyme activity,and an increase of denatured proteins.CmASMT may enhance the photosynthetic efficiency of chrysanthemum by regulating the synthesis of endogenous melatonin,while improving the activity of antioxidant enzymes,scavenging excess reactive oxygen species,alleviating membrane structure damage and degradation of photosynthetic pigments,thereby improving chrysanthemum thermotolerance.[Conclusion]CmASMT plays an important role in responding to high-temperature stress in chrysanthemum by regulating endogenous melatonin synthesis.关键词
菊花/高温胁迫/褪黑素/CmASMT/病毒诱导的基因沉默Key words
chrysanthemum/high temperature stress/melatonin/CmASMT/virus induced gene silencing引用本文复制引用
孟慧,罗丙玉,卢正宇,王鹏,康冬茹,郑成淑,王文莉..菊花CmASMT的克隆及其在高温抗性中的作用[J].中国农业科学,2025,58(8):1617-1629,13.基金项目
国家重点研发计划(2019YFD1001505)、山东省林业科技创新项目(LYCX06-2018-33) （2019YFD1001505）
