4种橡胶树叶绿体基因组密码子偏好性分析OA

To investigate the codon usage bias and its influencing factors in the chloroplast genomes of Hevea brasiliensis,the chloroplast genome codon usage bias of 4 Hevea brasiliensis varieties[Hevea brasiliensis,Hevea nitida,Hevea benthamiana and Hevea camargoana]was analyzed.The results showed that neutrality plot and ENC-plot analyses indicated that the chloroplast codon usage bias of the 4 Hevea brasiliensis varieties was influenced by both mutation pressure and natural selection,with natural selection exerting a greater effect on codon usage bias than mutation pressure.PR2-plot analysis revealed that the frequency of base T was higher than that of A,and the frequency of G was higher than that of C at the third codon position in the 4 Hevea brasiliensis varieties,suggesting a certain selective preference at the third codon position in the chloroplast genomes of these 4 Hevea brasiliensis varieties.This indicates that the codon usage bias of the 4 Hevea brasiliensis varieties is not solely determined by mutation but is also jointly regulated by multiple factors,including natural selection.The study demonstrated that natural selection is the primary factor driving codon usage bias in the chloroplast genomes of the 4 Hevea brasiliensis varieties,while mutation pressure is a seconda-ry factor.A total of 14 optimal codons were identified in each of the 4 Hevea brasiliensis varieties,with the majority of their third-position bases being A/U.