美味猕猴桃过氧化物酶基因 AdPOD27 的密码子偏好特征分析

为了解美味猕猴桃过氧化物酶基因 AdPOD27 的密码子偏好特征，本研究采用 CodonW1.4.2、SPSS19.0、MEGA5.2 和 EMBOSS 等软件分析 AdPOD27 的密码子偏好性参数，同时对单子叶植物和双子叶植物间 POD27 的密码子使用规律进行比较。结果表明，AdPOD27 有效密码子数（ENc）、密码子 G 和 C 含量（GC）、密码子第 3 位 G 或 C 的含量（GC3s）分别50.65、0.443 和 0.429，意示着 AdPOD27 密码子偏好性较弱但偏好使用含有较多 A 和 T 并以 A 或 T 结尾的密码子；单子叶植物和双子叶植物平均 ENc 值分别为 36.93 和 52.25，单子叶植物 POD27密码子偏好性普遍强于双子叶植物；聚类分析结果表明，物种间具有严格的密码子偏好性规律。此外，AdPOD27与猕猴桃基因组密码子使用频率存在一定差异。本研究结果为进一步开展 AdPOD27 基因功能和分子进化研究提供了科学依据。

Analysis of Codon Bias Characteristic of a Peroxidase Gene AdPOD27 in Actinidia deliciosa

To explore codon usage bias (CUB) characteristic of one peroxidase gene of Actinidia deliciosa (AdPOD27),  CUB parameters were analyzed by CodonW1.4.2, SPSS19.0, MEGA5.2 and EMBOSS in this study, and the CUB patterns between dicotyledon and monocotyledon were compared. The results showed that the effective number of codon (ENc), GC content (GC) and GC content on the 3 rd site (GC3s) was 50.65, 0.443 and 0.429, which indicated that CUB level of AdPOD27 was low, but it was bias toward the synonymous codons with A or T on the 3rd site. The average value of ENc in dicotyledon and monocotyledon was 36.93 and 52.25 respectively, meaning the CUB level of POD27 in monocotyledon was higher than that in dicotyledon. Based on phylogeny tree analysis, there were strict codon usage rules in different plants. In addition, there were some differences of codon usage frequency between AdPOD27 and kiwifruit genome. This study would provide a scientific basis for further research of gene function and molecular evolution of AdPOD27.