The following text describes a protein:
Function:
[Core protein]: Packages viral RNA to form a viral nucleocapsid, and promotes virion budding (Probable). Participates in the viral particle production as a result of its interaction with the non-structural protein 5A (By similarity). Binds RNA and may function as a RNA chaperone to induce the RNA structural rearrangements taking place during virus replication (By similarity). Modulates viral translation initiation by interacting with viral IRES and 40S ribosomal subunit (By similarity). Probably affects various cell signaling pathways, host immunity and lipid metabolism (Probable); [Envelope glycoprotein E1]: Forms a heterodimer with envelope glycoprotein E2, which mediates virus attachment to the host cell, virion internalization through clathrin-dependent endocytosis and fusion with host membrane (By similarity). Fusion with the host cell is most likely mediated by both E1 and E2, through conformational rearrangements of the heterodimer required for fusion rather than a classical class II fusion mechanism (By similarity); [Envelope glycoprotein E2]: Forms a heterodimer with envelope glycoprotein E1, which mediates virus attachment to the host cell, virion internalization through clathrin-dependent endocytosis and fusion with host membrane (By similarity). Fusion with the host cell is most likely mediated by both E1 and E2, through conformational rearrangements of the heterodimer required for fusion rather than a classical class II fusion mechanism (By similarity); [p13]: May function as a multimeric ion channel protein (viroporin); [Protease NS2]: Cysteine protease required for the proteolytic auto-cleavage between the non-structural proteins NS2 and NS3 (By similarity). The N-terminus of NS3 is required for the function of NS2 protease (active region NS2-3) (By similarity). Promotes the initiation of viral particle assembly by mediating the interaction between structural and non-structural proteins (By similarity); [Serine protease/helicase NS3]: Displays three enzymatic activities: serine protease with a chymotrypsin-like fold, NTPase and RNA helicase. NS3 serine protease, in association with NS4A, is responsible for the cleavages of NS3-NS4A, NS4A-NS4B, NS4B-NS5A and NS5A-NS5B (By similarity). The NS3/NS4A complex prevents phosphorylation of host IRF3, thus preventing the establishment of dsRNA induced antiviral state (By similarity). NS3 RNA helicase binds to RNA and unwinds both dsDNA and dsRNA in the 3' to 5' direction, and likely resolves RNA complicated stable secondary structures in the template strand (By similarity). Cleaves host MAVS/CARDIF thereby preventing the establishment of an antiviral state; [Non-structural protein 4B]: Induces a specific membrane alteration that serves as a scaffold for the virus replication complex (By similarity). This membrane alteration gives rise to the so-called ER-derived membranous web that contains the replication complex (By similarity). NS4B self-interaction contributes to its function in membranous web formation (By similarity); [Non-structural protein 5A]: Phosphorylated protein that is indispensable for viral replication and assembly; [RNA-directed RNA polymerase]: RNA-dependent RNA polymerase that performs primer-template recognition and RNA synthesis during viral replication. Initiates RNA transcription/replication at a flavin adenine dinucleotide (FAD), resulting in a 5'- FAD cap on viral RNAs. In this way, recognition of viral 5' RNA by host pattern recognition receptors can be bypassed, thereby evading activation of antiviral pathways.
Miscellaneous:
MISCELLANEOUS: Of all animal viruses, GBV-B is the most closely related to HCV.
Subcellular Localization:
[Core protein]: Virion. Host cytoplasm. Host lipid droplet. Note=Only a minor proportion of core protein is present in the nucleus (By similarity). Probably present on the surface of lipid droplets (By similarity); [Envelope glycoprotein E1]: Virion membrane; Single-pass type I membrane protein. Host endoplasmic reticulum membrane; Single-pass type I membrane protein. Note=The C-terminal transmembrane domain acts as a signal sequence and forms a hairpin structure before cleavage by host signal peptidase (By similarity). After cleavage, the membrane sequence is retained at the C-terminus of the protein, serving as ER membrane anchor (By similarity). A reorientation of the second hydrophobic stretch occurs after cleavage producing a single reoriented transmembrane domain (By similarity). These events explain the final topology of the protein (By similarity); [Envelope glycoprotein E2]: Virion membrane; Single-pass type I membrane protein. Host endoplasmic reticulum membrane; Single-pass type I membrane protein. Host lipid droplet. Note=The C-terminal transmembrane domain acts as a signal sequence and forms a hairpin structure before cleavage by host signal peptidase (By similarity). After cleavage, the membrane sequence is retained at the C-terminus of the protein, serving as ER membrane anchor (By similarity). A reorientation of the second hydrophobic stretch occurs after cleavage producing a single reoriented transmembrane domain (By similarity). These events explain the final topology of the protein (By similarity); [p13]: Host endoplasmic reticulum membrane; Multi-pass membrane protein; [Protease NS2]: Host endoplasmic reticulum membrane; Multi-pass membrane protein. Host lipid droplet. Note=Probably present on the surface of lipid droplets; [Serine protease/helicase NS3]: Host endoplasmic reticulum membrane; Peripheral membrane protein. Note=NS3 is associated to the ER membrane through its binding to NS4A; [Non-structural protein 4A]: Host endoplasmic reticulum membrane; Single-pass type I membrane protein. Note=Host membrane insertion occurs after processing by the NS3 protease; [Non-structural protein 4B]: Host endoplasmic reticulum membrane; Multi-pass membrane protein. Note=A reorientation of the N-terminus into the ER lumen occurs post-translationally; [Non-structural protein 5A]: Host endoplasmic reticulum membrane; Peripheral membrane protein. Host cytoplasm, host perinuclear region. Host mitochondrion. Host cytoplasm. Host nucleus. Host lipid droplet. Note=Host membrane insertion occurs after processing by the NS3 protease (By similarity). Localizes at the surface of lipid droplets (By similarity); [RNA-directed RNA polymerase]: Host cytoplasm. Host endoplasmic reticulum membrane; Single-pass type IV membrane protein. Note=Host membrane insertion occurs after processing by the NS3 protease.
Domain:
[Envelope glycoprotein E1]: The transmembrane regions of envelope E1 and E2 glycoproteins are involved in heterodimer formation, ER localization, and assembly of these proteins; [Envelope glycoprotein E2]: The transmembrane regions of envelope E1 and E2 glycoproteins are involved in heterodimer formation, ER localization, and assembly of these proteins; [Protease NS2]: The N-terminus of NS3 is required for the catalytic activity of protease NS2 (By similarity). The minimal catalytic region includes the C-terminus of NS2 and the N-terminus NS3 protease domain (active region NS2-3) (By similarity); [Serine protease/helicase NS3]: The N-terminal one-third contains the protease activity (By similarity). This region contains a zinc atom that does not belong to the active site, but may play a structural rather than a catalytic role (By similarity). This region is essential for the activity of protease NS2, maybe by contributing to the folding of the latter (By similarity). The NTPase/helicase activity is located in the twothirds C-terminus of NS3, this domain contains the NTPase and RNA-binding regions (By similarity); [Non-structural protein 4B]: Contains a glycine zipper region that critically contributes to the biogenesis of functional ER-derived replication organelles; [Non-structural protein 5A]: The N-terminus of NS5A acts as membrane anchor.
Sequence:
MPVISTQTSPVPAPRTRKNKQTQASYPVSIKTSVERGQRAKRKVQRDARPRNYKIAGIHDGLQTLAQAALPAHGWGRQDPRHKSRNLGILLDYPLGWIGDVTTHTPLVGPLVAGAVVRPVCQIVRLLEDGVNWATGWFGVHLFVVCLLSLACPCSGARVTDPDTNTTILTNCCQRNQVIYCSPSTCLHEPGCVICADECWVPANPYISHPSNWTGTDSFLADHIDFVMGALVTCDALDIGELCGACVLVGDWLVRHWLIHIDLNETGTCYLEVPTGIDPGFLGFIGWMAGKVEAVIFLTKLASQVPYAIATMFSSVHYLAVGALIYYASRGKWYQLLLALMLYIEATSGNPIRVPTGCSIAEFCSPLMIPCPCHSYLSENVSEVICYSPKWTRPVTLEYNNSISWYPYTIPGARGCMVKFKNNTWGCCRIRNVPSYCTMGTDAVWNDTRNTYEACGVTPWLTTAWHNGSALKLAILQYPGSKEMFKPHNWMSGHLYFEGSDTPIVYFYDPVNSTLLPPERWARLPGTPPVVRGSWLQVPQGFYSDVKDLATGLITKDKAWKNYQVLYSATGALSLTGVTTKAVVLILLGLCGSKYLILAYLCYLSLCFGRASGYPLRPVLPSQSYLQAGWDVLSKAQVAPFALIFFICCYLRCRLRYAALLGFVPMAAGLPLTFFVAAAAAQPDYDWWVRLLVAGLVLWAGRDRGPRIALLVGPWPLVALLTLLHLATPASAFDTEIIGGLTIPPVVALVVMSRFGFFAHLLPRCALVNSYLWQRWENWFWNVTLRPERFLLVLVCFPGATYDTLVTFCVCHVALLCLTSSAASFFGTDSRVRAHRMLVRLGKCHAWYSHYVLKFFLLVFGENGVFFYKHLHGDVLPNDFASKLPLQEPFFPFEGKARVYRNEGRRLACGDTVDGLPVVARLGDLVFAGLAMPPDGWAITAPFTLQCLSERGTLSAMAVVMTGIDPRTWTGTIFRLGSLATSYMGFVCDNVLYTAHHGSKGRRLAHPTGSIHPITVDAANDQDIYQPPCGAGSLTRCSCGETKGYLVTRLGSLVEVNKSDDPYWCVCGALPMAVAKGSSGAPILCSSGHVIGMFTAARNSGGSVSQIRVRPLVCAGYHPQYTAHATLDTKPTVPNEYSVQILIAPTGSGKSTKLPLSYMQEKYEVLVLNPSVATTASMPKYMHATYGVNPNCYFNGKCTNTGASLTYSTYGMYLTGACSRNYDVIICDECHATDATTVLGIGKVLTEAPSKNVRLVVLATATPPGVIPTPHANITEIQLTDEGTIPFHGKKIKEENLKKGRHLIFEATKKHCDELANELARKGITAVSYYRGCDISKIPEGDCVVVATDALCTGYTGDFDSVYDCSLMVEGTCHVDLDPTFTMGVRVCGVSAIVKGQRRGRTGRGRAGIYYYVDGSCTPSGMVPECNIVEAFDAAKAWYGLSSTEAQTILDTYRTQPGLPAIGANLDEWADLFSMVNPEPSFVNTAKRTADNYVLLTAAQLQLCHQYGYAAPNDAPRWQGARLGKKPCGVLWRLDGADACPGPEPSEVTRYQMCFTEVNTSGTAALAVGVGVAMAYLAIDTFGATCVRRCWSITSVPTGATVAPVVDEEEIVEECASFIPLEAMVAAIDKLKSTITTTSPFTLETALEKLNTFLGPHAATILAIIEYCCGLVTLPDNPFASCVFAFIAGITTPLPHKIKMFLSLFGGAIASKLTDARGALAFMMAGAAGTALGTWTSVGFVFDMLGGYAAASSTACLTFKCLMGEWPTMDQLAGLVYSAFNPAAGVVGVLSACAMFALTTAGPDHWPNRLLTMLARSNTVCNEYFIATRDIRRKILGILEASTPWSVISACIRWLHTPTEDDCGLIAWGLEIWQYVCNFFVICFNVLKAGVQSMVNIPGCPFYSCQKGYKGPWIGSGMLQARCPCGAELIFSVENGFAKLYKGPRTCSNYWRGAVPVNARLCGSARPDPTDWTSLVVNYGVRDYCKYEKLGDHIFVTAVSSPNVCFTQVPPTLRAAVAVDGVQVQCYLGEPKTPWTTSACCYGPDGKGKTVKLPFRVDGHTPGVRMQLNLRDALETNDCNSINNTPSDEAAVSALVFKQELRRTNQLLEAISAGVDTTKLPAPSIEEVVVRKRQFRARTGSLTLPPPPRSVPGVSCPESLQRSDPLEGPSNLPSSPPVLQLAMPMPLLGAGECNPFTAIGCAMTETGGGPDDLPSYPPKKEVSEWSDGSWSTTTTASSYVTGPPYPKIRGKDSTQSAPAKRPTKKKLGKSEFSCSMSYTWTDVISFKTASKVLSATRAITSGFLKQRSLVYVTEPRDAELRKQKVTINRQPLFPPSYHKQVRLAKEKASKVVGVMWDYDEVAAHTPSKSAKSHITGLRGTDVRSGAARKAVLDLQKCVEAGEIPSHYRQTVIVPKEEVFVKTPQKPTKKPPRLISYPHLEMRCVEKMYYGQVAPDVVKAVMGDAYGFVDPRTRVKRLLSMWSPDAVGATCDTVCFDSTITPEDIMVETDIYSAAKLSDQHRAGIHTIARQLYAGGPMIAYDGREIGYRRCRSSGVYTTSSSNSLTCWLKVNAAAEQAGMKNPRFLICGDDCTVIWKSAGADADKQAMRVFASWMKVMGAPQDCVPQPKYSLEELTSCSSNVTSGITKSGKPYYFLTRDPRIPLGRCSAEGLGYNPSAAWIGYLIHHYPCLWVSRVLAVHFMEQMLFEDKLPETVTFDWYGKNYTVPVEDLPSIIAGVHGIEAFSVVRYTNAEILRVSQSLTDMTMPPLRAWRKKARAVLASAKRRGGAHAKLARFLLWHATSRPLPDLDKTSVARYTTFNYCDVYSPEGDVFVTPQRRLQKFLVKYLAVIVFALGLIAVGLAIS