油棕油脂合成调控因子WRI1s的挖掘鉴定及表达分析

Identification and Expression Analysis of Oil Biosynthesis Related WRI1s Genes in Oil Palm

WRI1基因在油棕油脂合成过程中起着重要的调控作用,本研究旨在挖掘油棕WRI1 (EgWRI1)基因,并对其理化性质及组织表达特性进行分析。本研究利用生物信息学方法鉴定获得3个EgWRI1基因,均含有6个内含子,通过染色体定位分析发现EgWRI1-1和EgWRI1-2位于油棕的第5条染色体上,EgWRI1-3位于油棕第10条染色体上。3个基因均含有AP2保守结构域,编码氨基酸数目分别为337、338、367 aa,EgWRI1-1及EgWRI1-3蛋白的等电点均小于7,分别为6.51及6.29,EgWRI1-2蛋白的等电点大于7 (8.31),3个EgWRI1蛋白均为不稳定亲水蛋白,无信号肽,含有多个磷酸化位点,均定位在细胞核中,EgWRI1-1和EgWRI1-3以α-螺旋为主,EgWRI1-2以无规卷曲为主。聚类分析表明在遗传系数为0.625处,3个EgWRI1和ATWRI1同处一个分支,在0.680处,EgWRI1-1和EgWRI1-2的进化关系最近,且与EgWRI1-3聚为一类。定量PCR分析得知EgWRI1-1在中果皮80 d时的表达量最大,EgWRI1-2在果仁95 d中的表达量最大,在其他组织中表达很低或不表达;EgWRI1-3在各组织中的表达量均较低,该结果为深入研究EgWRI1-1和EgWRI1-2在油棕中果皮和果仁脂肪酸合成过程中的调控机理提供参考。

WRI1 genes play an important regulatory role in palm oil synthesis, this study aims to explore WRI1 genes and analyze its physical and chemical properties and tissue expression characteristics. Using bioinformatics method, a total of 3 EgWRI1 genes were found, all of which contained 6 introns. Through chromosome mapping analysis, it was found that EgWRI1-1 and EgWRI1-2 were located on chromosome 5 of oil palm, and EgWRI1-3 was located on chromosome 10 of oil palm. EgWRI1-1, EgWRI1-2 and EgWRI1-3 genes all contain AP2 domains,encoding 337, 338 and 367 aa, respectively. The isoelectric points of EgWRI1-1 and EgWRI1-3 were less than 7,which were 6.51 and 6.29, respectively, and that of Eg WRI1-2 were more than 7(8.31). They were hydrophilic proteins, no signal peptide, contain multiple phosphorylation sites. They exited in nucleus by subcellular localization analysis. The main structure of EgWRI1-1 and EgWRI1-3 was α-helix, EgWRI1-2 was random coil.Cluster analysis showed that at the genetic coefficient of 0.625, three EgWRI1 and AtWRI1 were in the same branch. At the genetic coefficient of 0.680, EgWRI1-1 and EgWRI1-2 had the closest evolutionary relationship and clustered with EgWRI1-3. Quantitative PCR analysis showed that the expression level of EgWRI1-1 was the highest at 80 day in mesocarp, the expression level of EgWRI1-2 was the highest at 95 day in endosperm, and EgWRI1-3 was not expressed in all tissues. The results laid a foundation for further study on the regulation mechanism of EgWRI1-1 and EgWRI1-2 in the process of fatty acid synthesis in mesocarp and endocarp of oil palm.