棉花DELLA蛋白GhGAI2b基因的克隆和功能初步分析

DELLA蛋白是赤霉素信号途径的负调节因子,在棉花纤维发育中有着重要作用。本研究采用同源克隆方法,从棉花中克隆DELLA蛋白Gh GAI2b基因,构建p BP35S:Gh GAI2b和p BP35S:Ghgai2b植物过表达载体,通过农杆菌介导的滴花法转化Col野生型拟南芥。结果表明,棉花DELLA蛋白Gh GAI2b包含了DELLA蛋白家族中所有的典型保守区域;转基因拟南芥表现出莲座叶半径变短,植株矮化,花序紧凑,花器官发育迟缓等生长发育受抑制表型。说明棉花DELLA蛋白Gh GAI2b基因可能参与GA信号途径抑制植物生长发育。

Cloning and Preliminary Functional Analysis of Cotton DELLA Protein GhGAI2b Gene

DELLA protein was a negative regulator in gibberellin（GA） signal pathway,and played an important role in cotton fiber development.In this study,the DELLA protein gene,GhGAI2b,was obtained by homology cloning method from Gossypium hirsutum L.The plant overexpression vectors,pBP35S：GhGAI2b and pBP35S：Ghgai2b,were constructed,and then transformed into Arabidopsis tba/iana （Col-0） with the method of Agrobacterium-mediated transformation.According to the results,the amino acid sequence of cotton GhGAI2b protein had all of the typical domains of DELLA proteins.The transgenic Arabidopsis lines showed the phenotype of short rosette leaf radius, dwarf plant, compact inflorescence,and retardant flower organs development.This study indicated that cotton DELLA protein GhGAI2b gene may be involved in the GA signal pathway to inhibit plant growth and development.