Fox G, Parry N R, Barnett P V, McGinn B, Rowlands D J, Brown F
Wellcome Biotechnology Ltd, Pirbright, Surrey, U.K.
J Gen Virol. 1989 Mar;70 ( Pt 3):625-37. doi: 10.1099/0022-1317-70-3-625.
The amino acid sequence RGD (arginine-glycine-aspartic acid) is highly conserved in the VP1 protein of foot-and-mouth disease virus (FMDV), despite being situated in the immunodominant hypervariable region between amino acids 135 and 160. RGD-containing proteins are known to be important in promoting cell attachment in several different systems, and we report here that synthetic peptides containing this sequence are able to inhibit attachment of the virus to baby hamster kidney (BHK) cells. Inhibition was dose-dependent and could be reversed on removal of the peptide. A synthetic peptide corresponding to a portion of the same hypervariable region but not containing the RGD sequence did not inhibit virus attachment under the same conditions. Antibody against the RGD region of VP1 blocked attachment of the virus to BHK cells, and neutralizing monoclonal antibodies, which neutralize virus by preventing cell attachment, were blocked by RGD-containing peptides from binding virus in an ELISA test. Cleavage of the C-terminal region of virus VP1 in situ with proteolytic enzymes reduced cell attachment, and antiserum against a peptide corresponding to this region was also able to inhibit attachment of virus to BHK cells. These results indicate that the amino acid sequence RGD at positions 145 to 147 and amino acids from the C-terminal region of VP1 (positions 203 to 213) contribute to the cell attachment site on FMDV for BHK cells.
氨基酸序列RGD（精氨酸-甘氨酸-天冬氨酸）在口蹄疫病毒（FMDV）的VP1蛋白中高度保守，尽管它位于氨基酸135至160之间的免疫显性高变区。已知含RGD的蛋白质在多种不同系统中对促进细胞黏附很重要，我们在此报告，含有该序列的合成肽能够抑制病毒与幼仓鼠肾（BHK）细胞的黏附。抑制作用呈剂量依赖性，去除肽后可逆转。对应于同一高变区一部分但不含RGD序列的合成肽在相同条件下不抑制病毒黏附。针对VP1的RGD区的抗体阻断病毒与BHK细胞的黏附，在ELISA试验中，通过阻止细胞黏附来中和病毒的中和性单克隆抗体被含RGD的肽阻断与病毒结合。用蛋白水解酶原位切割病毒VP1的C末端区域可减少细胞黏附，针对对应于该区域的肽的抗血清也能够抑制病毒与BHK细胞的黏附。这些结果表明，位于145至147位的氨基酸序列RGD以及VP1的C末端区域的氨基酸（203至213位）对FMDV上BHK细胞的细胞黏附位点有贡献。
