ID ENV_FRSF5 Reviewed; 409 AA. AC P03393; DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot. DT 21-JUL-1986, sequence version 1. DT 27-MAR-2024, entry version 124. DE RecName: Full=Glycoprotein 55; DE Short=gp55; DE Flags: Precursor; GN Name=env; OS Friend spleen focus-forming virus (isolate 502) (FSFFV). OC Viruses; Riboviria; Pararnavirae; Artverviricota; Revtraviricetes; OC Ortervirales; Retroviridae; Orthoretrovirinae; Gammaretrovirus; OC Spleen focus-forming virus. OX NCBI_TaxID=355329; OH NCBI_TaxID=10090; Mus musculus (Mouse). RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC RNA]. RX PubMed=6576374; DOI=10.1073/pnas.80.16.5037; RA Clark S.P., Mak T.W.; RT "Complete nucleotide sequence of an infectious clone of Friend spleen RT focus-forming provirus: gp55 is an envelope fusion glycoprotein."; RL Proc. Natl. Acad. Sci. U.S.A. 80:5037-5041(1983). RN [2] RP CHARACTERIZATION. RX PubMed=2159537; DOI=10.1128/jvi.64.6.2678-2686.1990; RA Watanabe N., Nishi M., Ikawa Y., Amanuma H.; RT "A deletion in the Friend spleen focus-forming virus env gene is necessary RT for its product (gp55) to be leukemogenic."; RL J. Virol. 64:2678-2686(1990). RN [3] RP ERRATUM OF PUBMED:2159537. RA Watanabe N., Nishi M., Ikawa Y., Amanuma H.; RL J. Virol. 64:5694-5694(1990). RN [4] RP REVIEW. RX PubMed=11090047; RA Ney P.A., D'Andrea A.D.; RT "Friend erythroleukemia revisited."; RL Blood 96:3675-3680(2000). RN [5] RP FUNCTION, AND INTERACTION WITH MOUSE MST1R ISOFORM SF-STK. RX PubMed=11483734; DOI=10.1128/jvi.75.17.7893-7903.2001; RA Nishigaki K., Thompson D., Hanson C., Yugawa T., Ruscetti S.; RT "The envelope glycoprotein of friend spleen focus-forming virus covalently RT interacts with and constitutively activates a truncated form of the RT receptor tyrosine kinase Stk."; RL J. Virol. 75:7893-7903(2001). RN [6] RP FUNCTION, SUBUNIT, AND INTERACTION WITH MOUSE EPOR. RX PubMed=12930840; DOI=10.1074/jbc.m302974200; RA Constantinescu S.N., Keren T., Russ W.P., Ubarretxena-Belandia I., RA Malka Y., Kubatzky K.F., Engelman D.M., Lodish H.F., Henis Y.I.; RT "The erythropoietin receptor transmembrane domain mediates complex RT formation with viral anemic and polycythemic gp55 proteins."; RL J. Biol. Chem. 278:43755-43763(2003). CC -!- FUNCTION: This envelope-like membrane glycoprotein is responsible for CC ligand-independent activation of the erythropoietin receptor EPOR CC leading to the abnormally rapid proliferation of erythroid precursor CC cells. In the first stage of Friend disease, constitutive activation of CC EPOR by gp55 causes uncontrolled, polyclonal proliferation of infected CC erythroblasts, leading to polycythemia (massive increase in the number CC of mature red cells). Host susceptibility to SSFV-induced CC erythroblastosis depends on the expression of the truncated isoform of CC MST1R receptor tyrosine kinase (MST1R isoform sf-Stk). Interaction with CC SSFV gp 55 results in constitutive tyrosine phosphorylation and CC activation of MST1R isoform sf-Stk. {ECO:0000269|PubMed:11483734, CC ECO:0000269|PubMed:12930840}. CC -!- SUBUNIT: Homooligomer (Probable). Forms heterooligomers with mouse CC EPOR, probably via their respective transmembrane domains. Forms CC covalent heterodimers with mouse MST1R isoform sf-Stk, probably via CC disulfide bonds. {ECO:0000269|PubMed:12930840, ECO:0000305}. CC -!- SUBCELLULAR LOCATION: Host endoplasmic reticulum membrane; Single-pass CC type I membrane protein. Host cell membrane; Single-pass type I CC membrane protein. Virion membrane {ECO:0000305}; Single-pass type I CC membrane protein {ECO:0000305}. Note=The envelope-like membrane CC glycoprotein gp55 is defective in its transport to the cell surface and CC remains associated predominantly with the rough endoplasmic reticulum CC (RER) membrane. It is almost not incorporated into virions. Host cell CC surface expression appears to be a prerequisite for its CC leukemogenicity. CC -!- MISCELLANEOUS: Compared to other gammaretroviruses which possess 2 CC envelope proteins (gp70 and p15E), gp55 corresponds to a gp70-p15E CC fusion protein with a deletion of a portion of p15E. It is encoded by CC the defective env gene of the virus. CC -!- MISCELLANEOUS: The Friend murine leukemia virus complex induces a rapid CC and fatal erythroleukemia in adult mice. It is the replication- CC defective spleen focus-forming virus (SFFV) contained in this complex CC that causes foci of proliferating erythroid cells in spleens of CC infected mice. The second component is a replication competent Friend CC murine leukemia virus (F-MuLV) that serves as a helper virus for SFFV. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; K00021; AAA46487.1; -; Genomic_RNA. DR PIR; A03993; VCVW5S. DR RefSeq; NP_041218.1; NC_001500.1. DR SMR; P03393; -. DR GlyConnect; 128; 2 N-Linked glycans. DR GlyConnect; 129; 7 N-Linked glycans, 1 O-Linked glycan. DR GlyConnect; 130; 4 N-Linked glycans, 1 O-Linked glycan. DR GlyConnect; 131; 4 N-Linked glycans, 1 O-Linked glycan. DR GlyConnect; 132; 4 N-Linked glycans. DR GlyConnect; 133; 4 N-Linked glycans. DR GlyConnect; 134; 2 N-Linked glycans, 3 O-Linked glycans. DR GlyConnect; 135; 1 N-Linked glycan, 2 O-Linked glycans. DR GlyConnect; 136; 1 N-Linked glycan, 2 O-Linked glycans. DR GlyCosmos; P03393; 4 sites, 22 glycans. DR GeneID; 1491889; -. DR KEGG; vg:1491889; -. DR GO; GO:0044167; C:host cell endoplasmic reticulum membrane; IEA:UniProtKB-SubCell. DR GO; GO:0020002; C:host cell plasma membrane; IEA:UniProtKB-SubCell. DR GO; GO:0016020; C:membrane; IEA:UniProtKB-KW. DR GO; GO:0019031; C:viral envelope; IEA:UniProtKB-KW. DR GO; GO:0055036; C:virion membrane; IEA:UniProtKB-SubCell. DR GO; GO:0019064; P:fusion of virus membrane with host plasma membrane; IEA:UniProtKB-KW. DR GO; GO:0046718; P:viral entry into host cell; IEA:UniProtKB-KW. DR GO; GO:0019062; P:virion attachment to host cell; IEA:UniProtKB-KW. DR Gene3D; 1.10.287.210; -; 1. DR Gene3D; 3.90.310.10; ENV polyprotein, receptor-binding domain; 1. DR InterPro; IPR008981; FMuLV_rcpt-bd. DR InterPro; IPR018154; TLV/ENV_coat_polyprotein. DR PANTHER; PTHR10424:SF77; BC035947 PROTEIN-RELATED; 1. DR PANTHER; PTHR10424; VIRAL ENVELOPE PROTEIN; 1. DR Pfam; PF00429; TLV_coat; 2. DR SUPFAM; SSF49830; ENV polyprotein, receptor-binding domain; 1. PE 1: Evidence at protein level; KW Disulfide bond; Fusion of virus membrane with host cell membrane; KW Fusion of virus membrane with host membrane; Glycoprotein; KW Host cell membrane; Host endoplasmic reticulum; Host membrane; KW Host-virus interaction; Membrane; Oncogene; Signal; Transmembrane; KW Transmembrane helix; Viral attachment to host cell; Viral envelope protein; KW Viral penetration into host cytoplasm; Virion; Virus entry into host cell. FT SIGNAL 1..32 FT /evidence="ECO:0000255" FT CHAIN 33..409 FT /note="Glycoprotein 55" FT /id="PRO_0000040718" FT TOPO_DOM 33..384 FT /note="Virion surface" FT /evidence="ECO:0000255" FT TRANSMEM 385..405 FT /note="Helical" FT /evidence="ECO:0000255" FT TOPO_DOM 406..409 FT /note="Intravirion" FT /evidence="ECO:0000255" FT REGION 254..280 FT /note="Disordered" FT /evidence="ECO:0000256|SAM:MobiDB-lite" FT CARBOHYD 43 FT /note="N-linked (GlcNAc...) asparagine; by host" FT /evidence="ECO:0000255" FT CARBOHYD 58 FT /note="N-linked (GlcNAc...) asparagine; by host" FT /evidence="ECO:0000255" FT CARBOHYD 296 FT /note="N-linked (GlcNAc...) asparagine; by host" FT /evidence="ECO:0000255" FT CARBOHYD 328 FT /note="N-linked (GlcNAc...) asparagine; by host" FT /evidence="ECO:0000255" SQ SEQUENCE 409 AA; 44777 MW; 407F56F769863D74 CRC64; MKGPAFSKPL KDKINPWGPL IVLGILIRAG VSVQHDSPHQ VFNVTWRVTN LMTGQTANAT SLLGTMTDAF PMLHFDLCDL IGDDWDETGL ECRTPGGRKR ARTFDFYVCP GHTVPTGCGG PREGYCGKWG CETTGQAYWK PSSSWDLISL KRGNTPKDRG PCYDSSVSSG VQGATPGGRC NPLVLKFTDA GKKASWDSPK VWGLRLYRPT GIDPVTRFSL TRQVLNIGPR IPIGPNPVII GQLPPSRPVQ VRLPRPPQPP PTGAASMVPG TAPPSQQPGT GDRLLNLVQG AYQALNLTNP DKTQECWLCL VSGPPYYEGV AVLGTNSNHT SALKEKCCFY ADHTGLVRDS MAKLRKRLTQ RQKLFESSQG WFEGSFNRSP WFTTLISTIM GLLIILLLLL ILLLWTLHS //