野生蕉ω-3脂肪酸去饱和酶基因FAD7密码子偏性分析

为了解FAD7的密码子使用特性,试验采用CodonW、SPSS19.0、MEGA5.0等软件和EMBOSS在线程序对野生蕉FAD7密码子偏性进行分析,同时与其他单/双子叶植物FAD7和模式生物基因组进行比较。结果显示,野生蕉FAD7密码子偏性水平较弱,密码子组成和结尾偏好使用G或C,而CUC、CAG和AGG等在该基因中具有较高的使用频率;物种间FAD7比较结果发现,单子叶植物FAD7密码子组成明显偏好G或C,而双子叶植物则完全相反;基于密码子使用频率FAD7聚类结果与CDS分类结果一致,均能将单/双子叶植物区分开来;此外,大肠杆菌原核表达受体系统可作为野生蕉FAD7基因异源表达理想试验体系。研究结果为野生蕉FAD7后续结构和功能研究提供了科学依据。

Codon Bias of ω-3 Fatty Acid Desaturase Gene (FAD7) in Musa itinerans

The codon bias of ω-3 fatty acid desaturase gene, FAD7, of Musa itinerans was analyzed using CodonW, SPSS19.0, MEGA5.0, and the EMBOSS online program.It was also compared with the FAD7s from different plants and genomes of model organisms.The results showed the codon bias of FAD7 in M.itinerans to be low and leaning toward the synonymous codons with G or C.And, it appeared that the codons CUC, CAG and AGG received a high usage frequency in the gene.In comparison with the FAD7s of different plants, the components of its monocotyledons were bias toward the use G or C, while dicotyledons the opposite.A cluster analysis on the FAD7s based on codon usage bias and CDS showed a same result.Hence, the dicotyledons and monocotyledons in the gene could be satisfactorily differentiated.Based on the frequency of codon usage, the prokaryotic expression system seemed to be suitable for heterologous expression of the FAD7 in M.itinerans.