沙棘ω-6脂肪酸去饱和酶基因的分子进化

Molecular Evolution of ω-6Fatty Acid Desaturase Gene in Hippophae RhamnoidesLinn.

运用生物信息学分析手段和在线数据库,对沙棘ω-6脂肪酸去饱和酶基因进行综合分析。结果显示:该基因全长为1 562 bp,开放读码框为1 152 bp;编码383个氨基酸,分子量为44 010.5道尔顿;等电点为8.63,带正电荷侧链的氨基酸与带负电荷侧链的氨基酸比例为29∶34;氨基酸组成中亮氨酸占10.7%,缬氨酸占7.8%,丙氨酸占6.8%;不稳定指数为36.73,脂肪指数为89.58,总平均疏水指数为-0.016,为亲水蛋白;其二级结构以无规则卷曲与折叠为主,属膜蛋白,有3个酪氨酸激酶II磷酸化位点、2个N-肉豆蔻酰化位点、4个蛋白激酶C磷酸化位点、3个N-糖基化位点、1个酪氨酸激酶磷酸化位点和1个微体C-端定位信号;该蛋白为质膜-脂肪酸去饱和酶域超家族蛋白(Membrane-FADS-like superfamily)。功能预测分析结果显示与其他物种的该去饱和酶特性相一致。

Based on the comprehensive analysis of ω-6 fatty acid desaturase gene using bioinformatics analysis software and online databases,we found out that this gene contains 1 562 bp nucleotide with an open reading frame(ORF) of 1 152 bp,comprising 383 amino acid residues with a predicted molecular mass of 44 010.5D.The isoelectric point is 8.63.The ratio of amino acids with positively charged side chains to amino acids with negatively charged side chains is 29∶ 34.Leu in this protein accounts for 10.7%,val 7.8% and ala 6.8%.The instability index of this protein is 36.73;fat index is 89.58;and the total average hydrophobic index is-0.016.It is shown that ω-6 fatty acid desaturase is water-soluble protein.In addition,the secondary structure is mainly based on random coil folding,and it is membrane proteins.There are three tyrosine kinase Ⅱ phosphorylation sites,two N-myristoylation sites,four protein kinase C phosphorylation sites,three N-sugar group sites,a tyrosine kinase phosphorylation site and a micro-body C-terminal positioning signal on the protein.Seabuckthorn ω-6 fatty acid desaturase enzyme predicts that the protein belongs to membrane-FADS-like superfamily.The function of forecast is consistent with the nature of the gene in other species.