苹果MdSWEET1基因生物信息学和表达分析

Bioinformatics and Expression Analysis of Gene MdSWEET1 in Malus ×domestica

糖转运蛋白SWEET作为一种新发现的蛋白在动植物中广泛存在,其对植物花蜜的生产和种子、花粉的发育有重要作用。本研究通过对本课题组获得的新基因MdSWEET1利用生物信息学软件进行分析,并利用实时荧光定量PCR对经低温预处理不同时间段后的苹果花药中该基因的表达量进行分析。生物信息学分析结果表明:MdSWEET1的cDNA中包含342 bp的开放阅读框(ORF),编码113个氨基酸,相对分子质量12.985 kD,等电点8.93,该基因编码蛋白的二级结构主要由无规则卷曲和α-螺旋构成,中间夹杂分布β-折叠;具有三个跨膜结构域,N端位于膜外;序列分析表明MdSWEET1与其他物种中发现的该蛋白氨基酸序列同源性很低。实时荧光定量分析表明,经低温预处理的苹果花药中MdSWEET1基因表达量随着冷处理时间的增加呈下调趋势,由此预测低温预处理阻碍了MdSWEET1基因的表达而影响其功能。该研究为进一步了解MdSWEET1对苹果花粉育性的影响提供理论依据。

SWEET, as the newfound sugar transporter which exist widely in plants and animals, it plays an important role in nectar production, pollen and seeds development. A obtained new gene MdSWEET1 is analyzed using the bioinformatics tools, and RT-qPCR was performed to detect the expression patterns during cold pretreatment of apple anther culture. The results indicated that: the open reading frame(ORF) of MdSWEET1 is 342 bp, and the predict protein is 12.985 kD and the theoretical PI is 8.93. Secondary structure of the protein is random coil and α-helix,while β-sheets spread in the whole protein. The protein contains three transmembrane domain, and its N-terminal is outside membrane. Sequence alignment showed a low amino acid sequence homology between MdSWEET1 and SWEET gene in other species. RT-q PCR results showed that MdSWEET1 gene expression in apple's anther is decrease as the prolonging of cold pre-treatment period and its function is affected. Furthermore, the results will lay the foundation for the understanding of MdSWEET1 function.