杧果Rab蛋白基因MiRab11的克隆及表达分析

Cloning and Expression Analysis of a GTP-binding Protein MiRab11 Gene from Mangifera indica

根据前期对杧果(Mangifera indica L.)胁迫差异分析中获得的Rab11片段,采用RT-PCR结合RACE技术,从‘四季杧’混合组织材料(叶、茎、花和果实)中克隆了一个Rab11完整编码区序列,命名为MiRab11。其cDNA全长902 bp,包含完整开放阅读框657 bp,编码218个氨基酸。同源性分析表明MiRab11与葡萄和柑橘的同源性最高(相似度均为97%)。实时荧光定量检测结果表明:MiRab11在杧果叶、茎、花和果实中均有表达,在嫩茎和花后70 d的成熟果实中的表达较高;在果实形成及发育初期表达量略有下调,但在果实成熟过程中表达量明显上调;逆境胁迫(低温、盐、干旱)处理可引起在叶或茎中上调表达;不同信号物质(脱落酸、水杨酸、双氧水)刺激均可引起叶中的表达上调。结果表明,MiRab11可能在杧果果实成熟和胁迫反应中发挥重要作用。

A MiRab11 gene,which belonged to small GTP-binding proteins Rab gene family,was cloned by RT-PCR and RACE from Mangifera indica mixed tissues(leaves,stems,flowers,and fruits). The full-length cDNA sequence was 902 bp and contained an open reading frame of 654 bp,which encoded a 218 amino acid protein. The deduced amino acid sequence exhibited high homology with Vitis vinifera and Citrus sinensis(97% similarity). Real-time quantitative PCR detection showed that the ubiquitously expressed MiRab11 in young stems and fruit of 70 d after flowering was much higher than in other tissues;The expression level of the gene was down-regulated during early fruit development from 20 d to 50 d after flowering and up-regulated during fruit ripening from 50 d to 70 d after flowering;It could be up-regulated under different stress treatments(low temperature,salt,and drought)and stimulated by different signal molecules stimulation(abscisic acid,salicylic acid,and hydrogen peroxide). In a word,a MiRab11 was identified from Mangifera indica,which might be associated with mango fruit ripening and play an important role in mango stress reaction.