蛋白质水平解析高山嵩草对青藏高原昼夜环境的响应（英文）

Protein Level Analysis of Kobresia pygmaea( Cyperaceae) Response to Diurnal Environment on the Tibetan Plateau

高山嵩草(Kobresia pygmaea)是高寒草甸的重要建群种,其生长发育同时受到年际、季节和昼夜环境变化的影响,但目前对高山嵩草响应昼夜环境变化的研究很少。本研究通过差异蛋白质组学的方法,结合抗氧化酶活性测定和蛋白质免疫印迹技术,分析了高山嵩草在一天中每4个小时的蛋白质表达变化。结果表明:在白天的高温、强光和紫外辐射,以及夜里的低温等不利条件下,高山嵩草体内的抗氧化酶、热休克蛋白和脱落酸代谢相关的蛋白质等能够被大量诱导表达,从而对细胞和机体起到保护作用。同时,受蛋白质调控的一些生命活动如光合作用会集中在较为适宜的时间段进行。通过体内蛋白质表达的可塑性和灵活性,高山嵩草能够有效地应对短时间里环境的变化。

Kobresia pygmaea is an important constructive species of alpine meadow on the Tibetan Plateau; its growth and development is influenced by both drastic environments of seasonal or inter-annual replacement and diurnal cycle. For a long time,studies about K. pygmaea adaption to alpine environment were mainly focused on the long-term adaptation while the diurnal responses were rarely reported. In the present study,we performed comparative proteomics approach,together with antioxidant enzyme assays and western blot,to analyze the variation of proteins expression in K. pygmaea every four hours from 2 a. m. to 22 p. m. in a day,which were collected from elevation of 4 800 m on the Nyainqentanglha Mountains. The results implicated that K. pygmaea was subjected to time-period abiotic environmental stresses,including high temperature,intense light and ultraviolet radiation in the day and low temperature in the night. To maintain normal life activities,K. pygmaea formed a complex set of strategies to deal with the potential damage. These strategies at least contained the plasticity and flexibility of antioxidant system,heat shock proteins accumulation,and abscisic acid metabolism. Meanwhile,a potential way named time-special activities regulated by proteins was also used to improve efficiency of survival,which meant some important biological processes,such as energy metabolism and photosynthesis,mostly occurred at more suitable time to avoid disadvantageous periods. These results supplied more knowledge about alpine plants adaptation to extreme day and night on the Tibetan Plateau.