豆科全基因组DGAT 基因家族的鉴定与进化分析

本文运用生物信息学方法在12个豆科植物基因组中对DGAT（甘油二酯酰基转移酶）基因进行了全基因组鉴定，发现在四倍体花生和大豆基因组中含有的基因拷贝数相对较多，分别为17、10，这可能是导致其油脂合成能力高于其他作物的重要因素。通过对家族基因进行系统发育分析，发现DGAT 基因在真双子叶植物分化之前已存在，在豆科植物中经历反复的全基因组加倍，使得家族得到扩张；并且串联重复对于家族扩增起到了不可忽视的作用，如葡萄中的两个旁系同源基因，由于串联重复使得基因拷贝数量提高了150%。大豆中DGAT 基因在不同的组织中表达模式与其系统发育关系也表现出了关联性。该基因家族相对保守，与豆科基因组进化基本保持了一致的进化速率。本研究对于认识豆科植物DGAT 基因进化过程具有重要的理论意义，同时在基因组学水平为大豆、花生等油脂合成品质改良提供了理论支撑。

Identification and evolutionary analysis of DGAT gene family in Legumes

Bioinformatics was used to identify DGAT (Diacylglycerol acyltransferase) gene in 12 legume ge?nomes. It was found that the gene copies in the tetraploid peanut and soybean genomes were relatively large, 17 and 10 respectively. It may be an important factor leading to higher oil synthesis capacity than other crops. Through phy?logenetic analysis of family genes, it was found that DGAT gene existed before the differentiation of eudicots, and re?peated whole genome double in legumes allowed the family to expand; and tandem repeats played an important role for family expansion. The role of the two paralogous genes in the grape, due to tandem repeats, increased the number of gene copies by 150%. The relationship between DGAT gene expression patterns in different tissues and its phylog?eny was also correlated. The gene family was relatively conservative and maintains a consistent evolution rate with the evolution of the leguminous genome. The study provided important genomic support for understanding the evolu? tion of DGAT genes on the legume scale and improving the quality of synthetic oils such as soybeans and peanut.