Immunogenetics. 2014 Jan;66(1):25-32. doi: 10.1007/s00251-013-0745-2.
The objective was to determine if single nucleotide polymorphisms (SNPs) in porcine MX2 gene affect its antiviral potential. MX proteins are known to suppress the multiplication of several viruses, including influenza virus and vesicular stomatitis virus (VSV). In domestic animals possessing highly polymorphic genome, our previous research indicated that a specific SNP in chicken Mx gene was responsible for its antiviral function. However, there still has been no information about SNPs in porcine MX2 gene. In this study, we first conducted polymorphism analysis in 17 pigs of MX2 gene derived from seven breeds. Consequently, a total of 30 SNPs, of which 11 were deduced to cause amino acid variations, were detected, suggesting that the porcine MX2 is very polymorphic. Next, we classified MX2 into eight alleles (A1-A8) and subsequently carried out infectious experiments with recombinant VSVΔG*-G to each allele. In A1-A5 and A8, position 514 amino acid (514 aa) of MX2 was glycine (Gly), which did not inhibit VSV multiplication, whereas in A6 and A7, 514 aa was arginine (Arg), which exhibited the antiviral ability against VSV. These results demonstrate that a SNP at 514 aa (Gly-Arg) of porcine MX2 plays a pivotal role in the antiviral activity as well as that at 631 aa of chicken Mx.
本研究旨在确定猪 MX2 基因中的单核苷酸多态性（SNPs）是否影响其抗病毒潜力。已知 MX 蛋白可抑制多种病毒（包括流感病毒和水疱性口炎病毒（VSV））的增殖。在基因组高度多态的家畜中，我们之前的研究表明，鸡 Mx 基因中的特定 SNP 与其抗病毒功能有关。然而，目前尚无关于猪 MX2 基因 SNPs 的信息。在这项研究中，我们首先对来自七个品种的 17 头猪的 MX2 基因进行了多态性分析。结果共检测到 30 个 SNP，其中 11 个推断会导致氨基酸变异，表明猪 MX2 非常多态。接下来，我们将 MX2 分为 8 个等位基因（A1-A8），并随后用重组 VSVΔG*-G 对每个等位基因进行了感染实验。在 A1-A5 和 A8 中，MX2 的第 514 位氨基酸（514aa）为甘氨酸（Gly），它不会抑制 VSV 的增殖，而在 A6 和 A7 中，514aa 为精氨酸（Arg），它对 VSV 具有抗病毒能力。这些结果表明，猪 MX2 第 514 位氨基酸（Gly-Arg）的 SNP 以及鸡 Mx 的第 631 位氨基酸的 SNP 在抗病毒活性中起着关键作用。
