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作 者 ：侯惠静, 王素英, 吴子健

期 刊 ：核农学报 2016年 30卷 7期 页码：1296-1307

关键词：原核微藻；psbA；密码子偏好性；系统聚类；

Keywords:microalgae, psbA, codon usage bias, hierarchical clustering,

摘 要 ：D1蛋白是光合作用反应中心的一种蛋白,研究编码该蛋白的psbA基因密码子的偏好性及聚类分析对原核微藻的分类具有重要意义。本研究利用MEGA和Codon W软件分析psbA基因的碱基组成和密码子适应指数、有效密码子数及相对密码子使用度等参数。结果表明,不同种属原核微藻的psbA 基因具有明显的密码子偏好性,且密码子使用模式多样,可反映该类群生物种属之间的亲缘关系。依据密码子偏好性的欧式平方距离系数进行聚类,证实密码子的偏好性与其物种的亲缘关系及进化存在一定的关系,其聚类结果可作为系统发育分析的重要补充。

Abstract:psbA gene (1 057~1 092 base pairs) is one of the important light- regulated genes in the chloroplast genome, which coded D1 protein with 352 to 363 amino acids in photosynthetic reaction centre. Analyzing the codon preference and the polygency of psbA gene is improtant to the classification of microalgae. The analysis of the effective number of codons value of psbA gene, codon adaptation index and relative synonymous codon usage of psbA genes with MEGA and codon W showed that codon bias existed in the psbA gene of prokaryotes microalgae. Diversity of codon usage patterns reflected the genetic relationship between the groups of biological species. Clustering results, which were obtained by squared Euclidean distance analysis for Relative Synonymous codon usage (RSCU) of psbA genes, showed that there was certain relationship between codon usage bias and the genetic relationship/species evolution, and consequently can serve as important complement to phylogenetic analysis.

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