甜橙TIFY基因家族的鉴定及其在成花诱导中的表达分析

Identification of TIFY Gene Family in Citrus sinensis and Its Expression Analysis in Flowering Induction

为了挖掘甜橙(Citrus sinensis)TIFY基因的功能,本研究从全基因组水平对甜橙TIFY基因家族进行生物信息学分析,并利用qRT-PCR检测其在不同甜橙品种花芽和叶片中的表达特异性。结果显示,甜橙全基因组共含有13个CsTIFY基因,其蛋白质大小为120~373 aa;这些基因分布于甜橙8条染色体上,均具有保守的TIFY结构域;系统发育分析将所有的CsTIFY蛋白聚类成8个亚族,位于同一亚族的CsTIFYs含有相似的基因结构和保守基序;转录组数据分析结果表明,不同组织中CsTIFYs的表达量存在差异,其中CsTIFY1、CsTIFY5、CsTIFY6、CsTIFY8、CsTIFY10和CsTIFY11在甜橙花和叶片中的表达量均较高。qRT-PCR检测结果表明,CsTIFYs在成花时间不同的两甜橙品种花芽和叶片中的相对表达水平均出现上调趋势,且采样各时期下早花品种‘赣南早’两组织中CsTIFYs的表达量均高于对照品种‘纽荷尔’,暗示CsTIFYs与甜橙花器发[JP3]育和成花转变密切相关。研究结果为深入了解CsTIFYs在甜橙成花诱导中的功能提供理论参考。

In order to explore the function of TIFY genes in Citrus sinensis,the CsTIFY gene family and its expression patterns in flowering induction at the genome database were analyzed by using bioinformatics method.The results showed that the whole genome contained 13 CsTIFY genes with a protein size from 120 aa to 373 aa,which were distributed on 8 chromosomes,and these genes had conserved TIFY domains.Phylogenetic analysis showed that all CsTIFY proteins were clustered into 8 groups,and the genes had similar gene structure and conserved motifs in the same group Transcriptome data analysis showed that the expression levels of the CsTIFY1,CsTIFY5,CsTIFY6,CsTIFY8,CsTIFY10 and CsTIFY11 were high in flowers and leaves of Citrus sinensis.The qRT-PCR results showed that the relative expression levels of the 6 CsTIFY genes were up-regulated in flower buds and leaves of two Citrus sinensis with different flowering time.The relative expression levels of these genes in the two tissues of the early-flowering varietiy(‘Gannan Zao’)were higher than the late-flowering variety(Newhall),indicating that CsTIFY genes were closely related to development floral organs and floral transformation of sweet orange.This study will provide a theoretical reference for further understanding the function of CsTIFY genes in flower induction.