花生中两个硬脂酰-ACP去饱和酶基因的克隆与序列分析

Cloning and Sequence Analysis of Glycerol-3-phosphate Acyltransferase Genes in Peanut

脂肪酸去饱和酶是不饱和脂肪酸合成途径的关键酶,催化脂肪酸链特定位置上脱氢形成双键。本研究通过构建花生种子全长cDNA文库,结合大规模EST测序和RACE克隆等方法,从花生中克隆得到了两个FAB2基因,分别命名为AhFAB2-2和AhFAB2-3。其中AhFAB2-2全长为1387bp,ORF为1158bp,理论分子量为43.7kD,理论等电点为5.69;AhFAB2-3全长为1452bp,ORF为1188bp,理论分子量为44.9kD,理论等电点为6.37。它们推导的氨基酸序列与拟南芥的相似性依次为60.8%和57.2%;与大豆的相似性分别是62.3%和59.3%。这两个基因在GenBank上的登录号分别为KF358459和KF358460。

Fatty acid desaturases are responsible for the insertion of double bonds into pre-formed fatty acid chains in reactions that require oxygen and reducing equivalents. Through construction of a full-length eDNA library of peanut （Arachis hypogaea ） seed, expressed sequence tag sequencing and rapid amplification of eDNA ends, two fatty acid desaturase genes, designated AhFAB2--2 and Ah- FAB2--3 were isolated from peanut. The sequence of AhFAB2--2 and AhFAB2--3 eDNA were 1387 bp and 1452 bp, and ORF were 1158 bp and 1188 bp, respectively. The molecular weight of AhFAB2 --2 and AhFAB2--3 were predicted to be 43.7 kD and 44.9 kD, and isoelectric points 5.69 and 6.37, respectively. The deduced amino acid had a high identity with the FAB2 proteins reported from other species. Amino acid similarities of AhFAB2--2 and AhFAB2--3 between peanut and Arabidopsisthaliana FAB2 - 3 were 60.8% and 57.2%, respectively; and amino a protein between peanut and Glycine max were 62 Cl 3 quences ofthe two genes were submitted to GenBank and their KF358460 respectively d similarities of AhFAB2--2 and Ah- and 59.3%, respectively. The se- accession number were KF358459 and