刺五加叶绿体基因组密码子的用法分析

目的:分析刺五加叶绿体基因组密码子的使用方式及其影响因素.方法:以刺五加叶绿体基因组的52条编码基因为材料,利用CodonW和SPSS软件进行多元统计分析和对应性分析.结果:刺五加叶绿体基因组密码子3个位置GC的量依次为46.46％,38.26％,29.88％,其中GC1与GC2呈极显著相关关系(P＜0.01),GC12与GC,的相关系数为0.205,未达到显著水平.同义密码子的相对使用频率(relative synonymous codon usage,RSCU)＞1的密码子共30个,其中29个以A或T碱基结尾.对应性分析的结果表明:第1轴显示了10.35％的差异,与有效密码子数(effective number of codons,ENC)和GC3显著相关,相关系数分别为-0.288,0.353;确定了刺五加叶绿体基因组的16个最优密码子.结论:刺五加叶绿体密码子第3位偏好以A或T碱基结尾,密码子使用模式受选择和突变及其他因素共同影响,其中选择的作用略大.

Analysis on codon usage of chloroplast genome of Eleutherococcus senticosus

Objective: To analyze the codon usage of chloroplast genome and the influencing factor in Eleutherococcus senticosus. Method: Codon of 52 genes, which were selected from the chloroplast genome sequence of E. senticosus, was multivariate statistical and correspondence analyzed using CodonW and SPSS software. Result: GC content at the three position of codons by turns was 46.46%,38.26%,29.88%, whereas GC₁ and GC₂ had a significant correlation coefficient (P<0.01). The correlation coefficient with GC₁₂ and GC₃ was 0.205 and was not significant coorelated. There were 30 codons which relative synonymous codon usage was greater than 1 and 29 codons end with A and T. In the corresponding analysis, the first axis shows 10.35% variation. And there was significant correlation coefficient between ENC and GC₃. The correlation coefficients with GC₃ and ENC were -0.288 and 0.353, respectively. We defined 16 codons from 16 amino acids as the major preference codons in chloroplast genome of E. senticosus. Conclusion: The third positions for all codon are preferred to ending with A and T. The codon usage bias is formed under effect of mutation and selection, as well as other factors. But the selection will have a far greater impact than others.