受光强调控参与茶树叶绿素代谢的NF-Y家族基因的鉴定与分析

Identification and Analysis of NF-Y Family Genes Involved in Chlorophyll Metabolism of Tea Plant Regulated by Light Intensity

核因子Y(nuclear factor Y,NF-Y)是一类光敏的、通过结合启动子CCAAT-box顺式作用元件,从而调控植物生长发育、叶绿素代谢、逆境胁迫响应等生物学过程的重要转录因子.叶绿素作为茶叶色泽的主要成分之一,在茶树中的形成受环境中光强条件的影响.目前,尚不清楚茶树中叶绿素代谢是否与NF-Y调控有关.研究检测了茶树在不同光强处理中NF-Y家族和叶绿素代谢途径结构基因的表达以及叶绿素质量分数,并对叶绿素代谢途径结构基因启动子区域CCAAT-box元件、基因表达与叶绿素代谢相关性进行了分析.结果显示,茶树中至少存在9个CsNF-Y基因和8个叶绿素代谢途径结构基因的表达响应光强.启动子区域100 bp内含CCAAT-box元件的基因在强光中表达具有上调趋势,茶树CsNF-Y可能参与了对这些基因的转录调控.相关性分析显示,CsUROS,CsMgCh2,CsCBR2表达水平与CsNF-YA5,CsNF-YA10表达水平,叶绿素质量分数显著相关.在光信号中,CsNF-YA5,CsNF-YA10可能通过CsUROS,CsMgCh2,CsCBR2调控了叶绿素代谢.

NF-Y(nuclear factor Y)is a class of important light-sensitive transcription factors that regulate biological processes such as plant growth and development,chlorophyll metabolism,and stress response by binding to the cis-acting element CCAAT-box of promoter.Chlorophyll,one of the main components of tea color,its formation in tea plants is affected by the condition of ambient light intensity.At present,it is not clear whether chlorophyll metabolism in tea plants is related to NF-Y regulation.This study examined the expression of NF-Y family and chlorophyll metabolism pathway structural genes,and chlorophyll content in tea plants under different light intensity treatments,and analyzed the correlation between the promoter region CCAAT-box element of chlorophyll metabolism pathway structural genes,genes expression,and chlorophyll metabolism.The results showed that at least 9 CsNF-Y genes and 8 chlorophyll metabolism pathway structural genes in tea plants were expressed in response to light intensity.Genes containing CCAAT-box elements within 100 bp of the promoter region had a tendency of up-regulated by strong light,and CsNF-Y may be involved in the transcriptional regulation of these genes.Correlation analysis showed that the expression levels of CsUROS,CsMgCh2,and CsCBR2 were significantly correlated with the expression levels of CsNF-YA5,CsNF-YA10,and chlorophyll content.In light signaling,CsNF-YA5 and CsNF-YA10 may regulate the chlorophyll metabolism through regulation of CsUROS,CsMgCh2,and CsCBR2.