摘要： 为了对MYB54基因的功能进行初步探究，对MYB54的进化保守性，蛋白质的二、三级结构，空间组织的特异性表达，高温胁迫响应，体外蛋白纯化和Western Blot检测以及转录激活活性进行了研究。结果表明，拟南芥中的MYB54与十字花科中的芥蓝、白菜、亚麻荠等同源性比较接近，分别达到了87%，87%，81%；与禾本科植物高粱、谷子和水稻的同源性较低，分别为54%，57%，47%；与小麦和番茄的同源性为42%。小麦中MYB54与拟南芥中MYB54在保守结构域，亲水性，二、三级结构都十分相似。RT-PCR结果表明，拟南芥中MYB54基因在果荚中表达量最高，暗示MYB54可能在生殖发育过程中发挥了一定的作用，并且拟南芥MYB54和小麦中的MYB54在高温胁迫下的表达量都显著降低，表明该基因在响应热胁迫中也发挥了重要功能。拟南芥中MYB54在18，30，37℃条件下，均可被成功诱导，在37℃条件下诱导纯化的蛋白量最高，Western Blot结果检测MYB54蛋白可以被正确翻译表达。利用酵母GAL4系统对MYB54的转录激活活性进行探究，发现MYB54在不与转录激活结构域结合的情况下，依然可以激活下游报告基因的表达，表明MYB54确实具有转录激活活性。初步对MYB54蛋白进行了结构、组织表达、蛋白诱导纯化、转录活性以及逆境表达分析，为MYB54在拟南芥及小麦生长发育过程中的功能研究提供一定的理论基础。

关键词: 拟南芥, MYB54, 组织表达, 诱导纯化, 转录激活, 逆境胁迫

Abstract: In order to make a preliminary exploration of the function of MYB54 gene, we have analyzed the evolutionary conservation of MYB54, the secondary and tertiary structure of the protein, and tissue specific expression, high temperature stress response, in vitro protein purification and Western Blot, detection and transcription activation activity. The results showed that the MYB54 protein in Arabidopsis was similar to Brassica oleracea, Brassica rapa and Camelina sativa in the cruciferous family, reaching 87%, 87%, 81%, respectively.It had low homology with grasses such as Brassica rapa, Setaria italica and Oryza sativa, which were 54%, 57%, 47% respectively, the homology with Triticum aestivum and Solanum lycopersicum was 42%.The MYB54 protein in wheat and Arabidopsis were very similar in conserved domains, hydrophilicity, secondary structure and tertiary structure. RT-PCR results showed that the MYB54 gene in Arabidopsis was expressed the most in pods, suggesting that MYB54 might play a certain role in the process of reproductive development, and the expression of MYB54 in Arabidopsis and wheat under high temperature stress was significantly reduced, indicating that this gene also played an important function in response to heat stress. MYB54 protein could be successfully induced under the conditions of 18, 30, 37℃. The amount of purified protein induced at 37℃ was the highest. Western Blot results showed that MYB54 protein could be correctly translated and expressed.The yeast GAL4 system was used to investigate the transcription activation activity of MYB54 gene, and it was found that MYB54 protein could still activate the expression of downstream reporter genes without binding to the transcription activation domain, indicating that MYB54 gene did have transcription activation activity. MYB54 protein structure, tissue expression, protein induction and purification, transcription activity and stress expression were preliminarily analyzed, which provided certain theoretical basis for the study of MYB54 function in the growth and development process of Arabidopsis thaliana and wheat.

Key words: Arabidopsis thaliana, MYB54, Tissue expression, Induction purification, Transcription activation, Abiotic stress

中图分类号: 

• Q943.2