Signal Peptide Requirements for Lymphocytic Choriomeningitis Virus Glycoprotein C Maturation and Virus Infectivity
Overview
Affiliations
Insertion of the lymphocytic choriomeningitis virus (LCMV) precursor glycoprotein C (GP-C) into the membrane of the endoplasmic reticulum is mediated by an unusual signal peptide (SP(GP-C)). It is comprised of 58 amino acid residues and contains an extended hydrophilic N-terminal region, two hydrophobic regions, and a short C-terminal region. After cleavage by signal peptidase, SP(GP-C) accumulates in cells and virus particles. In the present study, we identified the LCMV SP(GP-C) as being an essential component of the GP complex and show that the different regions of SP(GP-C) are required for distinct steps in GP maturation and virus infectivity. More specifically, we show that one hydrophobic region of SP(GP-C) is sufficient for the membrane insertion of GP-C, while both hydrophobic regions are required for the processing and cell surface expression of the GPs. The N-terminal region of SP(GP-C), on the other hand, is essential for pseudoviral infection of target cells. Furthermore, we show that unmyristoylated SP(GP-C) exposes its N-terminal region to the exoplasmic side. This SP(GP-C) can promote GP-C maturation but is defective in pseudoviral infection. Myristoylation and topology of SP(GP-C) in the membrane may thus hold the key to an understanding of the role of SP(GP-C) in GP-C complex maturation and LCMV infectivity.
Structure and receptor recognition by the Lassa virus spike complex.
Katz M, Weinstein J, Eilon-Ashkenazy M, Gehring K, Cohen-Dvashi H, Elad N Nature. 2022; 603(7899):174-179.
PMID: 35173332 DOI: 10.1038/s41586-022-04429-2.
Lassa virus glycoprotein complex review: insights into its unique fusion machinery.
Pennington H, Lee J Biosci Rep. 2022; 42(2).
PMID: 35088070 PMC: 8844875. DOI: 10.1042/BSR20211930.
Activation of the PDGF β Receptor by a Persistent Artificial Signal Peptide.
Petti L, Koleske B, DiMaio D J Mol Biol. 2021; 433(21):167223.
PMID: 34474086 PMC: 8530902. DOI: 10.1016/j.jmb.2021.167223.
Hulswit R, Paesen G, Bowden T, Shi X Viruses. 2021; 13(2).
PMID: 33672327 PMC: 7926653. DOI: 10.3390/v13020353.
Screening and Identification of Lassa Virus Entry Inhibitors from an FDA-Approved Drug Library.
Wang P, Liu Y, Zhang G, Wang S, Guo J, Cao J J Virol. 2018; 92(16).
PMID: 29899092 PMC: 6069169. DOI: 10.1128/JVI.00954-18.