棉花盐胁迫途径中蛋白磷酸化同源基因(GhSOS2)2种剪接体的克隆及表达分析

【目的】了解棉花在盐胁迫条件下相关基因的表达,并克隆与抗(耐)盐相关的重要基因。【方法】通过筛选棉花EST数据库,并对目标EST序列进行整合,对中棉所49在非盐胁迫和盐胁迫条件下进行处理并利用RT-PCR的方法克隆了质膜Na+/H+逆向转运蛋白途径中的1个蛋白磷酸化同源基因,命名为GhSOS2,并通过实时荧光定量PCR对其表达特征进行分析。【结果】序列分析表明,该基因成熟mRNA的剪接存在2种可选择性的剪接体,分别命名为GhSOS2a(GenBank登录号:GU188960)和GhSOS2b(GenBank登录号:GU188961),分别编码445和421个氨基酸残基。由于剪接方式的差异,导致GhSOS2a比GhSOS2b多出一个外显子(长度为72bp)。实时荧光定量PCR分析表明,GhSOS2a在非盐胁迫和盐胁迫条件下的根茎组织、叶组织均表达,但GhSOS2b仅在盐胁迫条件下的根茎组织、叶组织表达,且表达量远高于GhSOS2a。【结论】在棉花盐胁迫过程中,GhSOS2存在2种可选择性剪接体,而且可能主要是GhSOS2b参与棉花的质膜Na+/H+逆向转运蛋白途径并发挥一定作用。

Molecular Cloning and Expression Analysis of Two Splice Forms of the Protein Phosphorylation Homologous Gene (GhSOS2) During the Salt Stress Pathway in Cotton

【Objective】 The objective of this study is to understand the salt stress related genes expression and clone the key salt-tolerance genes under the conditions of salt tolerance in cotton. 【Method】 Through screening of the cotton EST databases and integration of the objective EST sequences, a homologous gene named GhSOS2 of plasma membrane Na+/H+ reverse transporter protein phosphorylation was obtained by RT-PCR method, respectively, under the conditions of non-salt and salt stress treatment of Zhongmiansuo 49. Meanwhile, the expression characteristics were analyzed by real time quantitative PCR method. 【Result】 The sequence analysis showed that there were two splice forms of GhSOS2a (GenBank accession number: GU188960) and GhSOS2b (GenBank accession number: GU188961), encoding 445 and 421 amino acid residues, respectively. Compared to GhSOS2b, an extra exon of 72 bp exists in GhSOS2a due to different splicing ways. Real time quantitative PCR analysis showed that GhSOS2a was expressed in the mixture tissue of root and stem, leaf tissue under both non-salt and salt stress conditions. However, GhSOS2b was expressed in the mixture tissue of root and stem, leaf tissue only under the conditions of salt stress. Furthermore, its expression was much higher than that of the GhSOS2a. 【Conclusion】 GhSOS2 gene was alternatively spliced into two kinds of splice forms under the condition of salt stress in cotton. The splice form GhSOS2b may be mainly involved and play an important role in the pathway of cotton plasma membrane Na+/H+ reverse transporter.