竹亚科叶绿体基因组的密码子使用偏性分析  

Condon preference of chloroplast genome of Bambusoideae

作　　者：吴妙丽 陈世品[2] 陈辉[2] WU Miaoli;CHEN Shipin;CHEN Hui(Fuzhou University of International Studies and Trade, Changle, Fujian 350202, China;College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China)

机构地区：[1]福州外语外贸学院,福建长乐350202 [2]福建农林大学林学院,福建福州350002

出　　处：《森林与环境学报》2019年第1期9-14,共6页Journal of Forest and Environment

基　　金：中国科学院科技服务网络计划资助项目(KFJ-3W-No1)

摘　　要：以3种竹亚科植物的叶绿体基因组编码基因为研究对象,分析基因的密码子偏性形成的主要因素。结果显示:3种竹子具有相似的密码子使用模式,均偏爱以A或T结尾的密码子。奇偶偏好性分析进一步证实密码子第3位T的出现频率高于A。通过中性分析发现,GC12与GC3并无显著相关性。奇偶偏好分析表明,4种碱基不成比例分布在密码子第3位上(CT>AG),说明选择压力可能起到重要作用。基于同义密码子的相对使用度(RSCU)的对应分析中,第1主向量轴仅解释了约10%的变异; 3种竹子的轴2一致地与CAI呈显著负相关(P<0.05);轴4与ENC、GC3呈极显著相关(P<0.05)。综合以上结果,竹亚科叶绿体基因密码子的使用偏性是由自然选择和碱基组成共同作用形成,选择压力起主要作用。Patterns of codon usage of3representative bamboos were analyzed to find out the factors shaping their codon bias.The results indicated that3bamboo plastomes harbored similar codon usage patterns,showing preference for codons with a3rd position nucleotide of A or T.Parity Rule2analysis(PR2)confirmed T was used more frequently than A.No correlation between GC12and GC3was established in the neutrality analysis.And the disproportionately used bases at the3rd position of codons(biased towards CT)hinted a pivotal role of natural selection.Furthermore,correspondence analysis based on values of relative synonymous codon usage(RSCU)yielded axis1that only accounted for10%variations of codon usage bias.Axis2value were detected to negative correlate with CAI(P<0.05),and axis4correlated with ENC and GC3(P<0.05).These results suggested the net effect of selection and mutation as determiners of the codon usage bias in bamboo plastomes;the selection power might play a leading role.

关 键 词：竹亚科 叶绿体基因组 密码子使用偏性 

分 类 号：Q943.2[生物学—植物学]