人溶菌酶基因的密码子优化设计及生物信息学初步分析

对猪乳蛋白密码子使用偏好性进行了分析,并基于其使用规则,在不改变编码氨基酸序列的基础上对人溶菌酶基因hLYZ的密码子进行了优化设计和生物信息学初步分析。研究结果表明,人hLYZ基因与猪乳蛋白相关基因的密码子使用频率存在明显差异,优化前后猪乳蛋白偏好性hLYZ基因（LYZ-Cas）共改变了109个碱基,约占hLYZ基因碱基总数的24.38%,G＋C含量由47.0%下降至43.8%。改造前后hLYZ基因CDS序列所翻译的氨基酸序列比对结果显示,其氨基酸序列没有发生变化,二级结构预测及Nc值计算显示,其能够在猪乳中相对高效表达。本研究旨在分析并比较优化前后hLYZ基因密码子的生物信息学变化,使其在猪乳蛋白中高效表达,对于生产富含人溶菌酶的hLYZ转基因克隆猪具有重要的理论意义,并且对于提高仔猪成活率,防治哺乳动物乳腺炎,提高乳品质等方面具有巨大的应用潜力。

Bioinformatics analysis and optimization of Homo sapiens lysozyme gene

In order to find a practically high expression way in the production of transgenic hLYZ pig, we found an ap- propriate approach for the optimization of the Homo sapiens lysozyme （hLYZ） gene. In this study,hLYZ gene was optimized based on the codon preference of Sus scrofa milk protein gene called casein, without changing the amino acid sequence. The results showed that 109 bases were changed in milk-based hLYZ gene （LYZ-Cas）. It accounted for 24.38% of all the hLYZ gene bases and some bioinformatics index were changed significantly. To be more spe- cific,Gq-C contents changed from 47.0% to 43.8% ,and the results of the mRNA structure forecasting showed that the mRNA secondary structure was beneficial to the expression of the gene. This research could make a preparation for growing hLYZ gene high level expression in transgenic pig milk. It could also be the first step in the production of hLYZ transgenic Sus scrofa.