Single Amino Acid Substitutions Surrounding the Icosahedral Fivefold Symmetry Axis Are Critical for Alternative Receptor Usage of Foot-and-Mouth Disease Virus

Gong, XH; Bai, XW; Li, PH; Bao, HF; Zhang, M; Chen, YL; Sun, P; Yuan, H; Huang, L; Ma, XQ; Fu, YF; Cao, YM; Li, K; Zhang, J; Li, ZY; Li, D; Lu, ZJ; Liu, ZX

Bai, XW; Liu, ZX (corresponding author), Chinese Acad Agr Sci, State Key Lab Vet Etiol Biol, Lanzhou Vet Res Inst, OIE China Natl Foot & Mouth Dis Reference Lab, Lanzhou 730046, Peoples R China.

VIRUSES-BASEL, 2020; 12 (10):

Abstract

The integrins function as the primary receptor molecules for the pathogenic infection of foot-and-mouth disease virus (FMDV) in vivo, while the acquisition of a high affinity for heparan sulfate (HS) of some FMDV variants could be privileged to facilitate viral infection and expanded cell tropism in vitro. Here, we noted that a BHK-adapted Cathay topotype derivative (O/HN/CHA/93tc) but not its genetically engineered virus (rHN), was able to infect HS-positive CHO-K1 cells and mutant pgsD-677 cells. There were one or three residue changes in the capsid proteins of O/HN/CHA/93tc and rHN, as compared with that of their tissue-originated isolate (O/HN/CHA/93wt). The phenotypic properties of a set of site-directed mutants of rHN revealed that E83K of VP1 surrounding the fivefold symmetry axis was necessary for the integrin-independent infection of O/HN/CHA/93tc. L80 in VP2 was essential for the occurrence of E83K in VP1 during the adaptation of O/HN/CHA/93wt to BHK-21 cells. L80M in VP2 and D138G in VP1 of rHN was deleterious, which could be compensated by K83R of VP1 for restoring an efficient infection of integrin-negative CHO cell lines. These might have important implications for understanding the molecular and evolutionary mechanisms of the recognition and binding of FMDV with alternative cellular receptors.

Download PDF


Full Text Link


打开APP