非生物胁迫下植物衰老和热激蛋白响应

Senescence and heat shock protein in plants in response to abiotic stress

非生物胁迫下植物细胞会提前启动衰老(senescence)程序以逃避胁迫,表现为叶绿素加速降解、光合作用减缓、蛋白质降解和活性氧增多等,进而导致植物早熟减产、品质下降。本文回顾了非生物胁迫下植物衰老过程中生理生化变化及热激蛋白(heat shock proteins,HSPs)响应,指出衰老表现为生理和分子方面的典型应激反应,同时受到激素及衰老响应基因的调节。HSPs作为分子伴侣协助蛋白质正确的折叠或组装,防止蛋白质不可逆聚集,参与蛋白跨膜运输及靶蛋白降解等多种生物功能,以维持细胞在不良发育条件下的稳态。本文为进一步研究植物非生物胁迫耐受性提供重要参考。

During abiotic stress,senescence may occur in plant cells in order to avoid stress,which is manifested in accelerated chlorophyll degradation,decelerated photosynthesis,protein degradation,and increased concentrations of reactive oxygen species,which leads to premature plant growth and reduces yield and quality.Abiotic stress-induced senescence manifests in typical physiological and molecular stress responses which are regulated by hormones and senescence response genes.Almost all stresses induce production of heat shock proteins(HSPs),whose transcription is regulated by heat shock factors.HSPs are molecular chaperones that assist in the correct folding or assembly of proteins,prevent irreversible protein aggregation,and participate in protein transmembrane transport and target protein degradation and other biological functions to maintain cell stability under poor developmental conditions.This article reviews the physiological and biochemical changes in plant senescence and HSP responses under abiotic stress so as to provide a reference for further research on plant abiotic stress tolerance.