Ko J H, Takada A, Mitsuhashi T, Agui T, Watanabe T
Laboratory of Experimental Animal Science, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Anim Genet. 2004 Apr;35(2):119-22. doi: 10.1111/j.1365-2052.2004.01096.x.
An attempt was made to determine whether amino acid variation at position 631 in the chicken Mx protein definitely influences antiviral specificity, using an artificial mutation technique by which a single amino acid was reciprocally substituted between Ser (AGT) and Asn (AAT) at position 631 of the negative and positive chicken Mx, respectively. Using permanently transfected 3T3 cell lines, the antiviral potential of chicken Mx against vesicular stomatitis virus infection was analysed. The results indicated that the phenotype of antiviral activity depends on the amino acid difference at position 631; that is, the genotype coding Asn at position 631 corresponds to the positive antiviral phenotype, and the genotype coding Ser corresponds to the negative phenotype. The present study has confirmed that the antiviral specificity of chicken Mx protein is determined by an amino acid substitution at the carboxy terminus.
通过人工突变技术，分别在鸡Mx蛋白阴性和阳性型的第631位将丝氨酸（AGT）和天冬酰胺（AAT）进行相互替换，试图确定鸡Mx蛋白第631位氨基酸变异是否确实影响抗病毒特异性。利用永久转染的3T3细胞系，分析了鸡Mx对水疱性口炎病毒感染的抗病毒潜力。结果表明，抗病毒活性表型取决于第631位的氨基酸差异；也就是说，在第631位编码天冬酰胺的基因型对应于阳性抗病毒表型，而编码丝氨酸的基因型对应于阴性表型。本研究证实，鸡Mx蛋白的抗病毒特异性是由羧基末端的氨基酸替换决定的。
