P[5]型猪C组轮状病毒Por2011 VP8*蛋白的表达及糖结合特征研究

Expression and Glycan-binding Specificity of the Por2011 VP8* Protein of P[5] Porcine Group-C Rotaviruses

轮状病毒(Rotaviruses,RVs)是引起人和动物病毒性腹泻的重要病原,本文旨在研究猪C组轮状病毒(Group C rotaviruses,RVCs)VP8*蛋白的受体结合特征。本研究合成一株P[5]型猪C组轮状病毒(Por2011)的VP8*基因,经体外原核表达,采用亲和层析纯化获得VP8*目的蛋白,利用糖点阵实验、寡糖结合实验研究其寡糖结合特征,再通过序列比对和突变分析确定其潜在受体结合位点。结果显示猪C组轮状病毒Por2011 VP8*蛋白与P1抗原特异性结合,但第108位氨基酸突变后的蛋白则不能与P1抗原结合。本研究表明猪C组轮状病毒的某些型别可能以P1抗原为潜在受体,该受体结合位点与人C组轮状病毒的受体结合位点较为接近,这为猪C组轮状病毒感染机制的研究提供了一定的依据和基础。

Rotaviruses(RVs)are one of the most common pathogens causing viral gastroenteritis.In order to explore the glycan-binding specificity of the VP8^*protein of porcine group C rotaviruses(RVCs),the VP8^*protein of a P[5]porcine group C rotavirus strain(Por2011)was expressed and purified.The glycan-binding specificity of Por2011 VP8^*was analyzed by glycans microarray and ELISA-based oligosaccharide-binding assays.The potential glycan binding sites of Por2011 VP8*were explored via the amino-acid mutation assay.The Por2011 VP8^*protein showed significant binding to P1 antigen,whereas the VP8^*protein with an Y108 L mutation did not show significant binding to P1 antigen.These data suggest that P1 antigen may be a potential attachment factor for the porcine Por2011 rotavirus.According to sequencing analyses,the glycan binding site of por2011 may be similar to that in human group C rotaviruses.This study provides a basis for understanding the infection mechanism of group C rotaviruses and is helpful for their surveillance.