海岛棉GbMYB25基因的克隆及表达分析

Cloning and expression analysis of GbMYB25 gene from Gossypium barbadense

关键词:  海岛棉  GbMYB25基因  克隆  表达分析

Key words:  Gossypium barbadense L.  GbMYB25 gene  cloning  expression analysis

摘要:

根据陆地棉GhMYB25的序列,设计1对引物,通过RT-PCR技术从海岛棉品种新海21号中克隆了1个同源基因,命名为GbMYB25。GbMYB25基因具有1个930 bp的开放阅读框,编码309个氨基酸,预测分子量约为34.762 ku,等电点为8.08,推测的氨基酸序列中含有2个高度保守的SANT结构域。GbMYB25基因序列包含2个内含子。氨基酸序列比对表明,该蛋白和其他高等植物的MYB蛋白有较高的同源性。进化树分析表明,GbMYB25基因和陆地棉GhMYB25基因处在同一进化树分支。亚细胞定位表明GbMYB25基因在细胞核中表达,实时荧光定量PCR结果表明GbMYB25基因在胚珠(0 doa)、纤维(5 dpa)和叶片中的表达量较高。以上结果表明,GbMYB25转录因子可能参与棉花纤维发育。

Abstract:

MYB transcription factors,as one of the largest gene families in plants,play an important role in multiple biological processes.According to the coding sequence of GhMYB25 gene,a pair of primers were designed.The homologous sequence of GhMYB25 gene,designated GbMYB25,was cloned from cotton (Gossypium barbadense L.) cultivar Xinhai21 using reverse transcription PCR (RT-PCR) methods.GbMYB25 gene contained an open reading frame (ORF) of 930 bp in length encoding 309 amino acids residues with a predicted molecular mass of 34.762 ku and a basic isoelectric point of 8.08,with two highly conserved SANT domains in the encoded putative protein.Genomic DNA sequence analysis showed that GbMYB25 contained 2 introns.Amino acid sequence alignment revealed that N-terminal of GbMYB25 shared high degree of identity with other higher plant MYB proteins.The phylogenetic tree showed that GbMYB25 was located at the same branch with GhMYB25.Subcellular localization showed that GbMYB25 expressed possibly in cell nucleus.The experiment results of real time PCR exhibited that GbMYB25 had a higher expression level in ovule (0 doa),fiber (5 dpa) and leaf.Above results suggested that GbMYB25 transcription factor might be involved in cotton fiber development.