香蕉枯萎病菌4号生理小种密码子使用偏好性分析

Analysis of Codon Usage Bias in Fusariumo xysporum f.sp. cubense Race 4

为了解香蕉枯萎病4号生理小种基因组的密码子使用特点,掌握其基因编码规律,以香蕉枯萎病4号生理小种基因组的13 303条高置信蛋白的编码信息为数据来源,借助CodonW等软件对蛋白质的每个氨基酸编码数据进行统计分析,研究获得了UCC和CCC等8个密码子为最优密码子,第三个碱基为C的密码子具有更高的选择性。进一步统计分析了mRNA的编码区长度,发现密码子使用偏好性随着编码区的延长而降低,较长编码区的基因对密码子的使用无显著偏好性,为建立和优化香蕉枯萎病菌的遗传转化系统具有直接的指导作用。

In order to explore the factors that influence the composition and coding characteristics of the codon, a total of 13 303 high confidence protein sequences predicted from Fusarium oxysporum f. sp. cubense race 4 genome were used as the data source. The code of each amino acid of the protein was statistically analyzed with CodonW isogenic processing software. A total 8 optimal codons including UCC and CCC were identified from the genome of Fusarium oxysporum f. sp. cubense race 4. The codons with the C in the last code demonstrated much higher usage. Further statistical analysis of the coding region of the mRNA found that the level of codon usage bias was declined along with the increasing on the length of coding region. The genes with longer coding region had no significant preference on codon bias. These results provided direct guidance for the establishment and optimization of genetic transformation system of Fusarium oxysporum possibly used for creating lost or reduced pathogenicity of Fusarium oxysporum mutants. It will be important to study the pathogenic gene function and reveal the mechanism of interaction between the banana and Fusarium oxysporum.