Ludert J E, Mason B B, Angel J, Tang B, Hoshino Y, Feng N, Vo P T, Mackow E M, Ruggeri F M, Greenberg H B
Department of Medicine, Stanford University School of Medicine, CA 94305, USA.
J Gen Virol. 1998 Apr;79 ( Pt 4):725-9. doi: 10.1099/0022-1317-79-4-725.
To explore further the role of VP4 as the rotavirus cell attachment protein, VP7 monoreassortants derived from the sialic-acid-dependent simian strain RRV and from the sialic-acid-independent human strains D, DS-1 and ST-3 were tested for susceptibility of infectivity of neuraminidase-treated MA-104 cells. Infectivity of RRV x D VP7 and RRV x ST-3 VP7 monoreassortants decreased when sialic acid was removed from the cell surface. However, of three separate RRV x DS-1 VP7 monoreassortants tested, only one was sialic-acid-dependent. Sequence analysis showed that both sialic-acid-independent strains contained a single amino acid change, Lys to Arg, at position 187. In addition, sialic-acid-independent infectivity was seen in one of 14 RRV VP4 neutralization escape mutants tested, and this strain was found to have a Gly to Glu change at amino acid position 150. These results indicate that positions 150 and 187 of VP4 play an important role in early rotavirus-cell interactions.
为了进一步探究VP4作为轮状病毒细胞附着蛋白的作用，对源自依赖唾液酸的猿猴毒株RRV以及不依赖唾液酸的人类毒株D、DS - 1和ST - 3的VP7单重配体进行了检测，以确定其对经神经氨酸酶处理的MA - 104细胞的感染敏感性。当从细胞表面去除唾液酸时，RRV×D VP7和RRV×ST - 3 VP7单重配体的感染性降低。然而，在测试的三个不同的RRV×DS - 1 VP7单重配体中，只有一个依赖唾液酸。序列分析表明，两种不依赖唾液酸的毒株在第187位都有一个氨基酸变化，即赖氨酸变为精氨酸。此外，在测试的14个RRV VP4中和逃逸突变体中，有一个表现出不依赖唾液酸的感染性，并且该毒株在氨基酸位置150处有一个甘氨酸到谷氨酸的变化。这些结果表明，VP4的第150位和第187位在轮状病毒与细胞早期相互作用中起重要作用。
