花生预苯胺酸脱氢酶基因AhADH的克隆及分子特性分析

Cloning and Characterization of the Arogenate Dehydrogenase Gene from Arachis hypogaca L.

通过改良的RACE技术从花生中分离并克隆出ADH全长cDNA序列,并命名为AhADH,其全长为1 155 bp,含一个编码269个氨基酸,长度为810 bp的开放阅读框。生物信息学分析显示AhADH蛋白的分子质量是30.65 kD,理论等电点是6.07,二级结构主要由α-螺旋和无规卷曲组成。序列比对表明花生ADH氨基酸序列含预苯酸/预苯胺酸脱氢酶结构域,且与多种其他植物的ADH具有高度同源性。qRT-PCR分析表明该基因具有组织表达差异性,且在茎中表达量最高。

The full-length eDNA encoding ADH was isolated by modified rapid amplification of eDNA ends （RACE） in peanut （A rachis hypogaca）. The eDNA, designated as A hA DH, was 1 155 base pairs （bp） long containing an open reading frame （ORF） of 810 bp encoding a protein of 269 amino acids. The bioinformaties approach prediction showed that AhADH with a predicted molecular weight of 30.65 kD and the theoretical isoelectric point （P/） of 6.07. The secondary structure was mainly composed of helix and random crimps. Alignments ofA. hypogaca ADH amino acid sequences revealed high homologies with other plant ADH, and contained prephenate/arogenate dehydrogenase domain. Real-time fluorescent quantitative PCR （qRT-PCR） analysis revealed that A hADH was preferentially expressed in stem compared with other tissues.