巴西橡胶树小橡胶粒子蛋白（SRPP）基因启动子的克隆及其功能分析

小橡胶粒子蛋白(SRPP)是巴西橡胶树中参与橡胶生物合成的重要蛋白因子之一。SRPP的氨基酸序列与橡胶延长因子(REF)和菜豆胁迫相关蛋白(PVSRP)的同源性分别为72%和68%。为了进一步研究SRPP基因表达及其调控的机制,作者采用接头连接介导的PCR散步法(ligation-mediated PCR),克隆了SRPP基因的启动子。序列分析表明,SRPP基因启动子中与光诱导相关的顺式元件占39%,可能属于光诱导型启动子,因此,SRPP基因的表达可能受光信号的调控。此外,SRPP基因启动子还具有热激响应元件(HSE)、干旱胁迫响应元件(MBS)、防卫和胁迫响应元件(TC-richrepeats)、脱落酸响应元件(ABRE)、赤霉素响应元件(GARE)和激发子响应元件(EIRE,Wbox)等,这表明橡胶树SRPP基因不仅参与调控橡胶生物合成,而且可能是橡胶树中响应逆境信号的抗性基因,在橡胶树抵御逆境胁迫的生理过程中发挥重要作用。

Cloning and functional analysis of the promoter of small rubber particle protein (SRPP) gene in Hevea brasiliensis

The small rubber particle protein (SRPP) is an important regulator of rubber biosynthesis in Hevea brasiliensis (rubber tree). The similarity of amino acid sequence of SRPP with those of rubber elonga- tion factor (REF) and phaseolus vulgaris stress-related protein (PvSRP) is 72% and 68%, respectively. For further investigation of gene expression of SRPP, the SRPP gene promoter was cloned with the method of ligationmediated PCR. Sequence analysis demonstrated that lightresponsive elements accounted for 39% of the cis-acting elements of the SRPP gene promoter, which indicates that SRPP promoter might be lightinducible and that the gene expression of SRPP could be regulated by light. In addition, SRPP gene promoter contains a variety of stress-responsive elements, such as HSE, MBS, TC-rich repeats, ABRE, EIRE and W box etc. These data suggest that SRPP is not only involved in rubber biosynthesis, but also plays an important role in response to various stresses in rubber trees.