两种不同生境植物棉花与雪莲CDPK1基因的克隆及生物信息学分析

Cloning and bioinformatics analysis of CDPK1 gene in Gossypium hirsutum and Sasussured involucrata from two different habitats

为了研究两种不同生境植物钙依赖性蛋白激酶基因1(CDPK1)的差异,分别从冷敏感作物陆地棉和高耐寒植物天山雪莲中克隆得到GhCDPK1和SikCDPK1基因。通过生物信息学分析发现,GhCDPK1和SikCDPK1的开放阅读框长度分别为1 764 bp和1 716 bp,各编码587和571个氨基酸。蛋白质表现为弱酸性,且不稳定,亲水;二级结构中以无规则卷曲和α-螺旋为主,三级结构同源建模成功;无跨膜结构域和信号肽,有多个磷酸化位点,但数量存在差异;均具有典型的CDPK保守结构域。GhCDPK1和SikCDPK1氨基酸序列同源性为79.9%,二者明显的区别在于GhCDPK1含有4个EF-hand基序,但SikCDPK1只存在2个EF-hand基序。进化分析结果表明,GhCDPK1与可可CDPK1亲缘关系最近,SikCDPK1与菊花CDPK2亲缘关系最近。

To study the functional differences of calcium-dependent protein kinase gene 1 （ CDPK1 ） in different habitats, 2 calcium-dependent protein kinase genes GhCDPK1 and SikCDPK1 were obtained from coldness-sensitive crop Gossypium hirsutum and hardy plant Sasussured involucrata Kar. et Kir, respectively. GhCDPK1 gene contains a 1 764-bp open reading frame encoding 587 amino acids, and SikCDPK1 contains a 1 716-bp open reading frame encoding 571 amino acids. The corresponding proteins are unstable, hydrophilic and mildly acidic, with random coil andα-helix dominating the secondary structure. Two deduced proteins have no transmembrane region and signal peptide. The protein sequences of Gh-CDPK1 and SikCDPK1 include multiple phosphorylation sites with different numbers, and contain a typical CDPK con-served domain. The GhCDPK1 and SikCDPK1 shared amino acid sequence homology of 79-9%. There are four conservative EF-hands in GhCDPK1 but only two EF-hands in SikCDPK1. Phylogenic analysis revealed that the GhCDPK1 protein was the closest to Theobroma cacao CDPK1, and the SikCDPK1 protein was the closest to Chrysanthemum boreale CDPK2.