A histidine residue of the influenza virus hemagglutinin controls the pH dependence of the conformational change mediating membrane fusion.

ABSTRACT:

Unlabelled

The conformational change of the influenza virus hemagglutinin (HA) protein mediating the fusion between the virus envelope and the endosomal membrane was hypothesized to be induced by protonation of specific histidine residues since their pKas match the pHs of late endosomes (pK(a) of ∼ 6.0). However, such critical key histidine residues remain to be identified. We investigated the highly conserved His184 at the HA1-HA1 interface and His110 at the HA1-HA2 interface of highly pathogenic H5N1 HA as potential pH sensors. By replacing both histidines with different amino acids and analyzing the effect of these mutations on conformational change and fusion, we found that His184, but not His110, plays an essential role in the pH dependence of the conformational change of HA.

SUBMITTER: Mair CM 

PROVIDER: S-EPMC4249083 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature