G
Domain
Isoform Membrane-bound glycoprotein G
Contains a linear heparin binding domain essential for virus attachment to the host.
Function
Isoform Membrane-bound glycoprotein G
Attaches the virion to the host cell membrane by interacting with heparan sulfate, initiating the infection (PubMed:10400758, PubMed:10864656, PubMed:3655746). Interacts with host CX3CR1, the receptor for the CX3C chemokine fractalkine, to modulate the immune response and facilitate infection (PubMed:11477410, PubMed:26107373, PubMed:26658574). Unlike the other paramyxovirus attachment proteins, lacks both neuraminidase and hemagglutinating activities (Probable).
Isoform Secreted glycoprotein G
Helps the virus escape antibody-dependent restriction of replication by acting as an antigen decoy and by modulating the activity of leukocytes bearing Fc-gamma receptors.
Post-translational modifications
Isoform Secreted glycoprotein G
Cleaved to give rise to the mature sG protein which lacks the transmembrane domain.
Isoform Membrane-bound glycoprotein G
N- and O-glycosylated (PubMed:4069997). May carry 30-40 separate O-linked carbohydrate chains distributed among the 91 serine and threonine residues (PubMed:1634876, PubMed:2164608, PubMed:3858865).
Isoform Membrane-bound glycoprotein G
Palmitoylated.
Sequence Similarities
Belongs to the pneumoviruses glycoprotein G family.
Cellular localization
- Isoform Membrane-bound glycoprotein G
- Virion membrane
- Single-pass type II membrane protein
- Host cell membrane
- Single-pass type II membrane protein
- Isoform Secreted glycoprotein G
- Secreted
- The protein is shed from infected cells before the appearance of progeny virus (By similarity). The initiation at the downstream methionine removes a portion of the transmembrane domain. The remaining hydrophobic portion of the sG protein is essential for translocating it into the lumen of the ER during translation and would likely maintain its membrane association until a proteolytic event releases the mature sG protein into the medium (By similarity).
Alternative names
Major surface glycoprotein G, Attachment glycoprotein G, Membrane-bound glycoprotein, mG, G