Yin Xiangzhen, Guo Xupeng, Hu Lizong, Li Shuangshuang, Chen Yuhong, Wang Jingqiao, Wang Richard R-C, Fan Chengming, Hu Zanmin
State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing 100101, China.
College of Advanced Agriculture Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
Plants (Basel). 2022 Apr 25;11(9):1156. doi: 10.3390/plants11091156.
Triacylglycerol (TAG) is the most important storage lipid for oil plant seeds. Diacylglycerol acyltransferases (DGATs) are a key group of rate-limiting enzymes in the pathway of TAG biosynthesis. In plants, there are three types of DGATs, namely, DGAT1, DGAT2 and DGAT3. , an allotetraploid plant, is one of the most important oil plants in the world. Previous studies of DGATs (BnaDGATs) have mainly focused on BnaDGAT1s. In this study, four DGAT1s, four DGAT2s and two DGAT3s were identified and cloned from ZS11. The analyses of sequence identity, chromosomal location and collinearity, phylogenetic tree, exon/intron gene structures, conserved domains and motifs, and transmembrane domain (TMD) revealed that BnaDGAT1, BnaDGAT2 and BnaDGAT3 were derived from three different ancestors and shared little similarity in gene and protein structures. Overexpressing showed that only four BnaDGAT1s can restore TAG synthesis in yeast H1246 and promote the accumulation of fatty acids in yeast H1246 and INVSc1, suggesting that the three subfamilies had greater differentiation in function. Transcriptional analysis showed that the expression levels of , and were different during plant development and under different stresses. In addition, analysis of fatty acid contents in roots, stems and leaves under abiotic stresses revealed that P starvation can promote the accumulation of fatty acids, but no obvious relationship was shown between the accumulation of fatty acids with the expression of under P starvation. This study provides an extensive evaluation of BnaDGATs and a useful foundation for dissecting the functions of BnaDGATs in biochemical and physiological processes.
三酰甘油（TAG）是油料植物种子中最重要的储存脂质。二酰甘油酰基转移酶（DGATs）是TAG生物合成途径中的一组关键限速酶。在植物中，有三种类型的DGATs，即DGAT1、DGAT2和DGAT3。甘蓝型油菜是一种异源四倍体植物，是世界上最重要的油料植物之一。先前对甘蓝型油菜DGATs（BnaDGATs）的研究主要集中在BnaDGAT1s上。在本研究中，从甘蓝型油菜中鉴定并克隆了4个DGAT1、4个DGAT2和2个DGAT3。对序列同一性、染色体定位和共线性、系统发育树、外显子/内含子基因结构、保守结构域和基序以及跨膜结构域（TMD）的分析表明，BnaDGAT1、BnaDGAT2和BnaDGAT3来源于三个不同的祖先，在基因和蛋白质结构上几乎没有相似性。过表达实验表明，只有4个BnaDGAT1s能够恢复酵母H1246中的TAG合成，并促进酵母H1246和INVSc1中脂肪酸的积累，这表明这三个亚家族在功能上有更大的分化。转录分析表明，BnaDGAT1、BnaDGAT2和BnaDGAT3在植物发育过程中和不同胁迫下的表达水平不同。此外，对非生物胁迫下根、茎和叶中脂肪酸含量的分析表明，磷饥饿可以促进脂肪酸的积累，但在磷饥饿条件下，脂肪酸的积累与BnaDGATs的表达之间没有明显的关系。本研究对BnaDGATs进行了广泛的评估，为剖析BnaDGATs在生化和生理过程中的功能提供了有用的基础。
