Protein Domain : Rubella membrane glycoprotein E1, domain 3 IPR042499

Type	Homologous_superfamily
Description	Rubella virus (RV), the sole member of the genus Rubivirus within the family Togaviridae, is a small enveloped, positive strand RNA virus. The nucleocapsid consists of 40S genomic RNA and a single species of capsid protein which is enveloped within a host-derived lipid bilayer containing two viral glycoproteins, E1 (58kDa) and E2 (42-46kDa). In virus infected cells, RV matures by budding either at the plasma membrane, or at the internal membranes depending on the cell type and enters adjacent uninfected cells by a membrane fusion process in the endosome, directed by E1-E2 heterodimers. The heterodimer formation is crucial for E1 transport out of the endoplasmic reticulum to the Golgi and plasma membrane. In RV E1, a cysteine at position 82 is crucial for the E1-E2 heterodimer formation and cell surface expression of the two proteins. E1 has been shown to be a type 1 membrane protein, rich in cysteine residues with extensive intramolecular disulphide bonds [ ].This superfamily makes up the membrane-distal domain 3 found in rubella membrane glycoprotein E1. Structurally, it consists of 9 beta strands and 1 alpha helix.
Short Name	Rubella_E1_3