Palmitoylation of the Bovine Foamy Virus Envelope Glycoprotein Is Required for Viral Replication

Abstract

Membrane proteins of enveloped viruses have been reported to undergo palmitoylation, a post-translational modification often having a critical role in the function of these viral proteins and hence viral replication. In this study, we report that the foamy virus (FV) envelope (Env) glycoprotein is palmitoylated. Specifically, we found that bovine foamy virus (BFV) Env (BEnv) is palmitoylated at amino acid positions C58 and C59 by BDHHC3 and BDHHC20 in a DHHC motif-dependent manner. In addition, mutations C58S and C58/59S significantly decrease cell surface expression of BEnv, subviral particle (SVP) egress, and its membrane fusion activity, thus ultimately inhibiting BFV replication. The C59S mutation exerts a minor effect in this regard. Taken together, these data demonstrate that the function of BEnv in the context of BFV replication is under the regulation of palmitoylation.

S-acylation of SARS-CoV-2 spike protein: Mechanistic dissection, in vitro reconstitution and role in viral infectivity

“…Our screen identified zDHHCs 2,3,6,11,12,20,21 and 24 as putative candidates that potentially palmitoylate the S protein. These zDHHCs intriguingly overlap with zDHHCs identified in the S-acylation of other viral proteins like, HA of Influenza A virus ( 30 ), GP5/M protein from Porcine reproductive and respiratory syndrome virus (PRRSV) ( 31 ), and BEnv from the bovine foamy virus ( 32 ). Interestingly, the level of S protein expression varied considerably with coexpression of the identified zDHHC, implicating a connection between S-acylation and biogenesis/stability of S protein, as observed in a recent study ( 33 ).…”

Effects of Chemokine Ligand 2 on Budding of Bovine Foamy Virus

“…For this purpose, we co-transfected the pCMV-3HA-BEnv plasmid with the pCE-puro-3Flag-BGag plasmid to detect the production of SVPs. Consequently, in the case of co-transfection of pCMV-3HA-BEnv and pCE-puro-3Flag-BGag plasmids, two parts of BEnv protein in the supernatant can be detected with anti-HA: BEnv-only SVPs [ 40 , 41 ] and BGag-BEnv SVPs [ 42 ], while anti-flag can only detect BGag bound to BEnv in the supernatant. Therefore, the level of BEnv in the supernatant cannot be regarded as a release level, we used the release of BGag protein in the supernatant as a measure of the release level of BFV SVPs.…”