true2008-02-262023-11-0880HBSAG_HBVD6Sequence analysis of HBV genomes isolated from patients with HBsAg negative chronic liver disease.Lai M.E.Mazzoleni A.P.Balestrieri A.Melis A.Porru A.1992-03EMBL/GenBank/DDBJNUCLEOTIDE SEQUENCE [GENOMIC DNA]Functions of the large hepatitis B virus surface protein in viral particle morphogenesis.Bruss V.Gerhardt E.Vieluf K.Wunderlich G.doi:10.1159/0001504711996Intervirology3923-31REVIEWRole of glycan processing in hepatitis B virus envelope protein trafficking.Block T.M.Lu X.Mehta A.Park J.Blumberg B.S.Dwek R.doi:10.1007/978-1-4615-5383-0_201998Adv. Exp. Med. Biol.435207-216REVIEWEnvelopment of the hepatitis B virus nucleocapsid.Bruss V.doi:10.1016/j.virusres.2004.08.0162004Virus Res.106199-209REVIEWHepatitis B virus pre-S mutants, endoplasmic reticulum stress and hepatocarcinogenesis.Wang H.C.Huang W.Lai M.D.Su I.J.doi:10.1111/j.1349-7006.2006.00235.x2006Cancer Sci.97683-688REVIEW1 site, No reported glycansHBV_HBSAGHBV_HBSAGvMSALarge envelope proteinL glycoproteinL-HBsAgLHBLarge S proteinLarge surface proteinMajor surface antigenSThe large envelope protein exists in two topological conformations, one which is termed 'external' or Le-HBsAg and the other 'internal' or Li-HBsAg. In its external conformation the protein attaches the virus to cell receptors and thereby initiating infection. This interaction determines the species specificity and liver tropism. This attachment induces virion internalization predominantly through caveolin-mediated endocytosis. The large envelope protein also assures fusion between virion membrane and endosomal membrane. In its internal conformation the protein plays a role in virion morphogenesis and mediates the contact with the nucleocapsid like a matrix protein.The middle envelope protein plays an important role in the budding of the virion. It is involved in the induction of budding in a nucleocapsid independent way. In this process the majority of envelope proteins bud to form subviral lipoprotein particles of 22 nm of diameter that do not contain a nucleocapsid.Li-HBsAg interacts with capsid protein and with HDV Large delta antigen. Isoform M associates with host chaperone CANX through its pre-S2 N glycan. This association may be essential for M proper secretion.The large envelope protein is synthesized with the pre-S region at the cytosolic side of the endoplasmic reticulum and, hence will be within the virion after budding. Therefore the pre-S region is not N-glycosylated. Later a post-translational translocation of N-terminal pre-S and TM1 domains occur in about 50% of proteins at the virion surface. These molecules change their topology by an unknown mechanism, resulting in exposure of pre-S region at virion surface.The large envelope protein is synthesized with the pre-S region at the cytosolic side of the endoplasmic reticulum and, hence will be within the virion after budding. Therefore the pre-S region is not N-glycosylated. Later a post-translational translocation of N-terminal pre-S and TM1 domains occur in about 50% of proteins at the virion surface. These molecules change their topology by an unknown mechanism, resulting in exposure of pre-S region at virion surface. For isoform M in contrast, the pre-S2 region is translocated cotranslationally to the endoplasmic reticulum lumen and is N-glycosylated.Isoform M is N-terminally acetylated by host at a ratio of 90%, and N-glycosylated by host at the pre-S2 region.Myristoylated.Systematic vaccination of individuals at risk of exposure to the virus has been the main method of controlling the morbidity and mortality associated with hepatitis B. The first hepatitis B vaccine was manufactured by the purification and inactivation of HBsAg obtained from the plasma of chronic hepatitis B virus carriers. The vaccine is now produced by recombinant DNA techniques and expression of the S isoform in yeast cells. The pre-S region do not seem to induce strong enough antigenic response.Belongs to the orthohepadnavirus major surface antigen family.Removed; by host1Large envelope protein425302389Intravirion; in internal conformation242Virion surface; in external conformation170Helical; Name=TM1; Note=In external conformation171191Intravirion; in external conformation192Helical; Name=TM2243263Virion surface264337Helical338358Intravirion359364Helical; Name=TM3365387Virion surface388Disordered54Pre-S163Pre-S1108Disordered73106Pre-S2109Polar residues8097N-myristoyl glycine; by hostN-linked (GlcNAc...) asparagine; by host309In isoform S.1996-11-0114266186edd59f969a33476536b2389b072557LLarge envelope proteinLHBL-HBsAgMGQNLSTSNPLGFFPDHQLDPASRANTANPDWDFNPNKDTWPDANKDGAGAFGLGLTPPHGGLLGWSPQAQGILHTVPANPPPASTNRQTGRQPTPLSPPLRDTHPQAVQWNSTTFHQTLQDPRVRGLYFPAGGSSSGTVNPVPTTASPLSSIFSRIGDPVTNMENITSGFLGPLLVLQAGFFLLTRILTIPQSLDSWWTSLNFRGGTTVCLGQNSQSPTSNHSPTSCPPTCPGYRWMCLRGFIIFLFILLLCLIFLLVLLEYQGMLHVCPLIPGTTTTSTGPCKTCTTPAQGNSMFPSCCCTKTSDGNCTCIPIPSSWAFAKYLWEWASVRFSWLSLLVPFVQWFVGLSPTVWLSAIWMMWYWGPSLYSILSPFLPLLPIFFCLWVYISSmall envelope proteinSHBS-HBsAgMENITSGFLGPLLVLQAGFFLLTRILTIPQSLDSWWTSLNFRGGTTVCLGQNSQSPTSNHSPTSCPPTCPGYRWMCLRGFIIFLFILLLCLIFLLVLLEYQGMLHVCPLIPGTTTTSTGPCKTCTTPAQGNSMFPSCCCTKTSDGNCTCIPIPSSWAFAKYLWEWASVRFSWLSLLVPFVQWFVGLSPTVWLSAIWMMWYWGPSLYSILSPFLPLLPIFFCLWVYItruetrue