| IED ID | IndEnz0002005406 |
| Enzyme Type ID | protease005406 |
| Protein Name |
Envelope glycoprotein Env polyprotein Cleaved into: Surface protein SU ; Transmembrane protein TM ; R-peptide |
| Gene Name | env |
| Organism | Xenotropic MuLV-related virus (isolate VP62) (XMRV) |
| Taxonomic Lineage | Viruses Riboviria Pararnavirae Artverviricota Revtraviricetes Ortervirales Retroviridae Orthoretrovirinae Gammaretrovirus unclassified Gammaretrovirus Murine leukemia-related retroviruses XMRV-related viruses Xenotropic MuLV-related virus Xenotropic MuLV-related virus (isolate VP62) (XMRV) |
| Enzyme Sequence | MESPAFSKPLKDKINPWGPLIIMGILVRAGASVQRDSPHQVFNVTWKITNLMTGQTANATSLLGTMTDTFPKLYFDLCDLVGDNWDDPEPDIGDGCRSPGGRKRTRLYDFYVCPGHTVLTGCGGPREGYCGKWGCETTGQAYWKPSSSWDLISLKRGNTPKGQGPCFDSSVGSGSIQGATPGGRCNPLVLEFTDAGKRASWDAPKTWGLRLYRSTGADPVTLFSLTRQVLNVGPRVPIGPNPVITEQLPPSQPVQIMLPRTPRPPPSGAASMVPGAPPPSQQPGTGDRLLNLVEGAYLALNLTSPDKTQECWLCLVSGPPYYEGVAVLGTYSNHTSAPANCSVTSQHKLTLSEVTGQGLCIGAVPKTHQALCNTTQKTSDGSYYLASPAGTIWACSTGLTPCLSTTVLNLTTDYCVLVELWPKVTYHSPNYVYGQFEKKTKYKREPVSLTLALLLGGLTMGGIAAGVGTGTTALVATKQFEQLQAAIHTDLGALEKSVSALEKSLTSLSEVVLQNRRGLDLLFLKEGGLCAALKEECCFYADHTGVVRDSMAKLRERLNQRQKLFESGQGWFEGLFNRSPWFTTLISTIMGPLIVLLLILLFGPCILNRLVQFVKDRISVVQALVLTQQYHQLKSIDPEEVESRE |
| Enzyme Length | 645 |
| Uniprot Accession Number | Q27ID8 |
| Absorption | |
| Active Site | |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | |
| DNA Binding | |
| EC Number | |
| Enzyme Function | FUNCTION: The surface protein (SU) attaches the virus to the host cell by binding to its receptor. This interaction activates a thiol in a CXXC motif of the C-terminal domain, where the other Cys residue participates in the formation of the intersubunit disulfide. The activated thiol will attack the disulfide and cause its isomerization into a disulfide isomer within the motif. This leads to SU displacement and TM refolding, and is thought to activate its fusogenic potential by unmasking its fusion peptide. Fusion occurs at the host cell plasma membrane (By similarity). {ECO:0000250}.; FUNCTION: The transmembrane protein (TM) acts as a class I viral fusion protein. Under the current model, the protein has at least 3 conformational states: pre-fusion native state, pre-hairpin intermediate state, and post-fusion hairpin state. During viral and target cell membrane fusion, the coiled coil regions (heptad repeats) assume a trimer-of-hairpins structure, positioning the fusion peptide in close proximity to the C-terminal region of the ectodomain. The formation of this structure appears to drive apposition and subsequent fusion of viral and target cell membranes. Membranes fusion leads to delivery of the nucleocapsid into the cytoplasm (By similarity). {ECO:0000250}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Chain (3); Coiled coil (1); Compositional bias (1); Disulfide bond (8); Glycosylation (7); Lipidation (1); Motif (3); Peptide (1); Region (4); Sequence conflict (3); Signal peptide (1); Site (2); Topological domain (2); Transmembrane (1) |
| Keywords | Cleavage on pair of basic residues;Coiled coil;Disulfide bond;Fusion of virus membrane with host cell membrane;Fusion of virus membrane with host membrane;Glycoprotein;Host cell membrane;Host membrane;Host-virus interaction;Lipoprotein;Membrane;Palmitate;Reference proteome;Signal;Transmembrane;Transmembrane helix;Viral attachment to host cell;Viral envelope protein;Viral penetration into host cytoplasm;Virion;Virus entry into host cell |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: [Transmembrane protein]: Virion membrane {ECO:0000250}; Single-pass type I membrane protein {ECO:0000250}. Host cell membrane {ECO:0000250}; Single-pass type I membrane protein {ECO:0000250}.; SUBCELLULAR LOCATION: [Surface protein]: Virion membrane; Peripheral membrane protein. Host cell membrane {ECO:0000250}; Peripheral membrane protein {ECO:0000250}. Note=The surface protein is not anchored to the viral envelope, but associates with the virion surface through its binding to TM. Both proteins are thought to be concentrated at the site of budding and incorporated into the virions possibly by contacts between the cytoplasmic tail of Env and the N-terminus of Gag (By similarity). {ECO:0000250}.; SUBCELLULAR LOCATION: [R-peptide]: Host cell membrane; Peripheral membrane protein. Note=The R-peptide is membrane-associated through its palmitate. {ECO:0000250}. |
| Modified Residue | |
| Post Translational Modification | PTM: Specific enzymatic cleavages in vivo yield mature proteins. Envelope glycoproteins are synthesized as an inactive precursor that is N-glycosylated and processed likely by host cell furin or by a furin-like protease in the Golgi to yield the mature SU and TM proteins. The cleavage site between SU and TM requires the minimal sequence [KR]-X-[KR]-R. The R-peptide is released from the C-terminus of the cytoplasmic tail of the TM protein upon particle formation as a result of proteolytic cleavage by the viral protease. Cleavage of this peptide is required for TM to become fusogenic (By similarity). {ECO:0000250}.; PTM: The CXXC motif is highly conserved across a broad range of retroviral envelope proteins. It is thought to participate in the formation of a labile disulfide bond possibly with the CX6CC motif present in the transmembrane protein. Isomerization of the intersubunit disulfide bond to an SU intrachain disulfide bond is thought to occur upon receptor recognition in order to allow membrane fusion (By similarity). {ECO:0000250}.; PTM: The transmembrane protein is palmitoylated. {ECO:0000250}.; PTM: The R-peptide is palmitoylated. |
| Signal Peptide | SIGNAL 1..33; /evidence=ECO:0000255 |
| Structure 3D | |
| Cross Reference PDB | - |
| Mapped Pubmed ID | - |
| Motif | MOTIF 311..314; /note=CXXC; /evidence=ECO:0000250; MOTIF 530..538; /note=CX6CC; /evidence=ECO:0000250; MOTIF 630..633; /note=YXXL motif; contains endocytosis signal; /evidence=ECO:0000250 |
| Gene Encoded By | |
| Mass | 69,876 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda |