木薯MeSR34a的表达分析和植物表达载体的构建

Expression Analysis of Cassava MeSR34a and Construction of Plant Expression Vector

富含丝氨酸和精氨酸的SR蛋白(serine/arginine-rich proteins, SR)是一类重要的剪接因子,其在植物响应非生物胁迫过程中具有重要作用。MeSR34a是木薯SR蛋白家族成员之一。为了解析MeSR34a的功能,首先对MeSR34a进行生物信息学分析,并通过实时荧光定量PCR (qRT-PCR)分析了MeSR34a在木薯不同组织部位和胁迫处理后的表达水平。最后,从木薯中克隆MeSR34a基因,构建植物表达载体。生物信息学分析结果表明MeSR34a基因全长为768 bp,编码255个氨基酸,蛋白大小大约为29 kD,等电点pI为10.45,含有11个外显子和10个内含子,是亲核的碱性蛋白。MeSR34a蛋白包含RRM结构域和RS结构域,与拟南芥MeSR34a的亲缘关系最近。荧光定量PCR结果发现,MeSR34a在木薯根中表达水平最高。在山梨醇(Sorbitol)、脱水(Dehydration)、脱落酸(ABA)和氯化钠(NaCl)处理条件下,MeSR34a的表达水平显著上调或下调,这些结果表明MeSR34a参与调控木薯响应非生物胁迫。本研究有助于后续深入研究MeSR34a在非生物胁迫中的功能。

Serine/arginine-rich proteins(SR proteins) is an important splicing factor, and plays an important role in response to abiotic stress in plant. MeSR34 a is one of the members of SR protein family in cassava. In order to study the function of MeSR34 a, we firstly performed the analysis of MeSR34 a gene through bioinformatics. Then we analyzed the expression levels of MeSR34 a in different tissues and various stress treatments of cassava plants by quantitative real-time PCR(qRT-PCR). Finally, we cloned the MeSR34 a gene from cassava, and then constructed the plant expression vector. Bioinformatics analysis showed that full length of MeSR34 a gene was 768 bp and encoded 255 amino acids. The MeSR34 a protein was about 29 kD, and the isoelectric point was 10.45. MeSR34 a was a nucleophilic basic protein and contained 11 exons and 10 introns. MeSR34 a protein contains RRM motif and RS domain, and had the closest relationship with Arabidopsis MeSR34 a. The qRT-PCR results showed that the expression levels of MeSR34 a was the highest in cassava roots, and the MeSR34 a transcript levels were varied greatly under sorbitol, dehydration, ABA and NaCl conditions, respectively, indicating that MeSR34 a gene have a pivotal role in the regulation of plant response to abiotic stress. The above results would contribute to the further study of the function of MeSR34 a in abiotic stress.