棉花溶血磷酸酯酰转移酶(LPAT)家族基因的发掘和表达分析

Genome-wide Identification of Lysophosphatidic Acid Acyltransferase Gene Family and Their Expression Analysis in Cotton

棉花油脂合成相关代谢在控制油分形成、纤维发育等进程中起着重要作用。溶血磷脂酰基转移酶(LPAT)是植物油脂代谢过程中的一个关键酶。本研究利用雷蒙德氏棉全基因组数据库,通过生物信息学技术,鉴定并获得8个棉花LPAT家族基因的全序列和染色体定位等信息。通过序列比对进行系统进化和分类分析,明确这8个家族基因分布在6条染色体上,分为4亚类,其中第I类和第III类中各含2个基因、第II类1个、第IV类3个。组织表达分析表明这8个基因在棉花营养和生殖阶段均表现表达多样性。LPAT6和LPAT8在17 d胚珠中表达水平很高,推测在油脂合成代谢调控中起重要作用。8个LPAT基因均在纤维中优势表达,其中LPAT2、LPAT3和LPAT4表达水平更高,推测LPAT家族基因的表达参与棉纤维发育进程。

Metabolism related to lipids synthesis plays an important role in regulating both oil biosynthesis and fiber development in cotton. Lysophosphatidic acid acyltransferase （LPAT） is a key enzyme in oil biosynthesis pathway in plant. In this study, eight cotton LPAT family genes were identified and their gene sequences, chromosome location were obtained, based onG. raimondii genome database （http：//www.phytozome.net/） and bioinformatic method. These LPAT members were anchored on six chromo-somes inG. raimondii. Phylogenetic analysis showed that LPAT candidate genes were classified into four groups, with two mem-bers each in group I and group III, one in group II, and three in group IV. The expression patterns of LPAT genes revealed their important roles in diverse functions in the developmental stages of vegetative and reproductive growth in cotton.LPAT6and LPAT8 showed the highest expression level in ovules at 17 days post-anthesis, which might play an important role in regulating oil biosynthesis. Eight genes showed the preferential expression level in fiber development stages. Among them,LPAT2,LPAT3, and LPAT4showed the higher expression level in fiber than in other tissues and organs, implying their association with cotton fiber development.