OsI2基因的克隆及其植物表达载体的构建

Cloning of OsI2 Gene and its Plant Expression Construct

在旱稻IRAT109干旱胁迫下cDNA芯片分析结果的基础上,通过RT-PCR,5'-RACE及3'-RACE方法,从IRAT109总RNA中扩增得到了干旱胁迫下芯片表达谱中上升表达强度第二的基因全长序列,命名为OsI2,全长有523bp,并对基因序列结构进行了分析。该基因与全长cDNA文库中的CT836140.1有99%同源。OsI2基因编码产物对应1个包含57个氨基酸的开放阅读框(ORF),为一功能未知蛋白。其编码产物也可能对应两个中间相隔19bp的较小ORFs(43个氨基酸和42个氨基酸),都是功能未知的蛋白。在pBI121载体的基础上,将OsI2基因与CaMV35S连接成功构建了pBI121-OsI2植物表达载体,为进一步研究其功能创造了条件。

Full length cDNA, named OsI2, was cloned by using RT-PCR, 5＇-RACE and 3＇-RACE methods from total RNA of drought-stressed rice IRAT109, which would be the second most up-regulated gene based on the resuits of cDNA microarray analysis of drought-stressed upland rice （cv. IRAT109）. The structure of OsI2 gene was analyzed that the 523 bp length sequence of OsI2 gene showed 99% homology with a cDNA CT836140.1 registered in the full-length cDNA library. It might be predicted a putative transcription product with an open reading frame （ORF） encoding 57 amino acids, or possible two ORFs encoding 43 and 42 amino acids with an 19 bp interval, which both ORFs would be assigned to unknown functional proteins. Plant expression vector was constructed by fusing OsI2 gene with promoter CaMV35 in plant expression vector pBI121, which would provide a construct for further functional study for drought stress resistance.