香蕉果实冷胁迫相关MaWRKY11转录因子的特性、互作蛋白筛选与鉴定

Characterization and Interacting-Protein Identification of Cold-Responsive MaWRKY11 from Banana Fruit

摘要:

从香蕉（Musa acuminata）果实冷害的数字基因表达谱中筛选并分离了一个WRKY转录因子，命名为MaWRKY11。MaWRKY11具有2个WRKY保守结构域，属于I类WRKY成员。亚细胞定位证实MaWRKY11定位在细胞核，是核蛋白。转录活性分析揭示MaWRKY11具有转录激活活性，并且激活区在N端。实时荧光定量PCR分析表明MaWRKY11受冷胁迫诱导，外源茉莉酸甲酯（MeJA）处理减轻香蕉果实冷害的同时也上调了其表达。另外，利用MaWRKY11的C端作为诱饵进行酵母双杂筛库发现，MaWRKY11可与脱水诱导早期应答蛋白MaERD相互作用。以上结果表明MaWRKY11可能通过与逆境相关蛋白如MaERD互作来响应香蕉果实的冷胁迫。

Abstract:

In the present study, one WRKY transcription factor, designated as MaWRKY11, was isolated and identified from Digital Gene Expression Data (DGE) of banana fruit. MaWRKY11 contains double WRKY conserved domains and belongs to Group I of WRKY family. Subcellular localization indicated that MaWRKY11 was exclusively localized in the nucleus, implying that it was a nuclear protein. Transactivation assay showed that MaWRKY11 possessed transcriptional activity in yeast cells and the transcriptional domain located at its N-terminus. Moreover, real-time quantitative PCR displayed that MaWRKY11 was induced by chilling stress, and MeJA treatment which could alleviate chilling injury of banana fruit, up-regulated the expression of MaWRKY11. In addition, C-terminus of MaWRKY11 was used as a bait to screen its potential interacting proteins by using yeast two-hybrid system, and it was found that MaWRKY11 could interact with Early Responsive to Dehydration Protein, MaERD, which was also induced by cold. Taken together, these results suggest that MaWRKY11 might respond to chilling stress through interacting with stress-related proteins, such as MaERD.