巴西橡胶树HbNAC24基因克隆和表达分析

Clone and Expression of HbNAC24 Gene from Hevea brasiliensis

该研究以巴西橡胶树为实验材料,从橡胶树胶乳cDNA中克隆了NAC转录因子基因（HbNAC24）完整开放阅读框（ORF）,并通过酵母实验和实时荧光定量PCR技术,进行转录激活活性分析和表达分析.结果显示：（1）HbNAC24基因ORF为1 167 bp,编码388个氨基酸,在N端第7～174氨基酸之间含有一个典型的NAC结构域.（2）酵母实验表明,HbNAC24具有转录激活活性,转录激活区在高度变异C端,具备了NAC转录因子的基本特征.（3）序列比对和系统进化分析表明,HbNAC24蛋白属于NAC转录因子家族中的TIP亚族.（4）实时荧光定量PCR分析结果发现,HbNAC24基因在叶中的表达量显著高于其他部位;割胶和茉莉酸（JA）处理均能够诱导HbNAC24表达上调.研究认为,HbNAC24基因可能参与植物的生长发育和胁迫应答过程.

The whole open reading frame（ORF） sequence of HbNAC24 was cloned from cDNA of Hevea brasiliensis latex,and the transcriptional activation activity and expression profile of HbNAC24 were carried out using Real-time PCR and yeast assay system. The results indicated that： （1）HbNAC24 has an OPR of 1 167 bp,encoding a protein with 388 amino acids. It＇s N-terminal region had a conserved NAC domain from amino acid 7 to 174. （2）Yeast assay showed that HbNAC24 protein possessed transcriptional activa- tion activity and the activation domain was located in the highly divergent C-terminal region in yeast assay system. （3）Sequence alignment and phylogenetic analysis revealed that HbNAC24 was a member of a NAC transcription factor family belonging to TIP subgroup. （1）The real-time PCR indicated that expression lev- el of HbNAC24 in leaves was significantly higher than that in other parts of the rubber tree. The expression of HbNAC24 in latex was induced by tapping and jasmonic acid（JA）. The results suggested that HbNAC24 may be involved in response to stress and developmental processes in rubber tree.