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对57个来自不同地区的大豆花叶病毒(SMV)分离物的基因组序列进行密码子使用偏性与进化分析。结果显示,SMV基因组GC含量较低;GC3<50%,说明SMV偏好使用以A/T结尾的密码子;SMV基因组密码子3个位置的GC含量均相互呈极显著相关(P<0.01),说明密码子3个位置的碱基组成相关;ENC值为49.42~51.78,密码子偏性存在但并不显著;对应性分析结果表明,第1轴显示67.84%的差异,ENC、GC3、GC12之间的相关性均达极显著水平(P<0.01),说明密码子的偏性与碱基突变相关;中性绘图及ENC绘图分析均表明密码子使用模式主要受碱基突变影响;密码子使用频率比较结果显示SMV存在19个最优密码子;RSCU的聚类分析证明SMV密码子偏性与病毒地理来源相关。
Genomic sequences of 57 mosaic virus (SMV) isolates from different regions were subjected to codon usage bias and evolutionary analysis. The results showed that GC content of SMV genome was low and GC3 was less than 50%, indicating that SMV prefers to use A / T-terminated codons. GC content of SMV genomic codons at three positions are significantly correlated with each other (P <0.01) The results showed that there was a 67.84% difference in the first axis between ENC, GC3 and GC12 (P <0.01), indicating that codon bias is related to base mutation. Neutral mapping and ENC mapping analysis showed that codon usage pattern was mainly affected by base mutation. Codon usage The results of frequency comparison showed that 19 optimal codons existed in SMV. Cluster analysis of RSCU proved that SMV codon bias was related to the geographical origin of virus.