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Q67875 (HBSAG_HBVD6) Reviewed, UniProtKB/Swiss-Prot

Last modified January 9, 2013. Version 54. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
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Names and origin

Protein namesRecommended name:
Large envelope protein
Alternative name(s):
L glycoprotein
L-HBsAg
Short name=LHB
Large S protein
Large surface protein
Major surface antigen
Gene names
Name:S
OrganismHepatitis B virus genotype D subtype ayw (isolate Italy/CI/1992) (HBV-D) [Complete proteome]
Taxonomic identifier489489 [NCBI]
Taxonomic lineageViruses › Retro-transcribing viruses › Hepadnaviridae › Orthohepadnavirus ›
Virus hostHomo sapiens (Human) [TaxID: 9606]
Pan troglodytes (Chimpanzee) [TaxID: 9598]

Protein attributes

Sequence length389 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

The 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 assumes fusion between virion membrane and endosomal membrane Probable. In its internal conformation the protein plays a role in virion morphogenesis and mediates the contact with the nucleocapsid like a matrix protein By similarity.

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 By similarity.

Subunit structure

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 By similarity.

Subcellular location

Virion membrane By similarity.

Domain

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.

Post-translational modification

Myristoylated By similarity.

Biotechnological use

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.

Sequence similarities

Belongs to the orthohepadnavirus major surface antigen family.

Alternative products

This entry describes 2 isoforms produced by alternative splicing and alternative initiation. [Align] [Select]
Isoform L (identifier: Q67875-1)

Also known as: Large envelope protein; LHB; L-HBsAg;

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
Isoform S (identifier: Q67875-2)

Also known as: Small envelope protein; SHB; S-HBsAg;

The sequence of this isoform differs from the canonical sequence as follows:
     1-163: Missing.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Initiator methionine11Removed; by host By similarity
Chain2 – 389388Large envelope protein
PRO_0000319087

Regions

Topological domain2 – 242241Intravirion; in internal conformation Potential
Topological domain2 – 170169Virion surface; in external conformation Potential
Transmembrane171 – 19121Helical; Note=In external conformation; Potential
Topological domain192 – 24251Intravirion; in external conformation Potential
Transmembrane243 – 26321Helical; Potential
Topological domain264 – 33774Virion surface Potential
Transmembrane338 – 35821Helical; Potential
Topological domain359 – 3646Intravirion Potential
Transmembrane365 – 38723Helical; Potential
Topological domain388 – 3892Virion surface Potential
Region2 – 163162Pre-S
Region2 – 108107Pre-S1
Region109 – 16355Pre-S2

Amino acid modifications

Lipidation21N-myristoyl glycine; by host By similarity
Glycosylation3091N-linked (GlcNAc...); by host By similarity

Natural variations

Alternative sequence1 – 163163Missing in isoform S.
VSP_031410

Sequences

Sequence LengthMass (Da)Tools
Isoform L (Large envelope protein) (LHB) (L-HBsAg) [UniParc].

Last modified November 1, 1996. Version 1.
Checksum: A39542B416E48F24

FASTA38942,661
        10         20         30         40         50         60 
MGQNLSTSNP LGFFPDHQLD PASRANTANP DWDFNPNKDT WPDANKDGAG AFGLGLTPPH 

        70         80         90        100        110        120 
GGLLGWSPQA QGILHTVPAN PPPASTNRQT GRQPTPLSPP LRDTHPQAVQ WNSTTFHQTL 

       130        140        150        160        170        180 
QDPRVRGLYF PAGGSSSGTV NPVPTTASPL SSIFSRIGDP VTNMENITSG FLGPLLVLQA 

       190        200        210        220        230        240 
GFFLLTRILT IPQSLDSWWT SLNFRGGTTV CLGQNSQSPT SNHSPTSCPP TCPGYRWMCL 

       250        260        270        280        290        300 
RGFIIFLFIL LLCLIFLLVL LEYQGMLHVC PLIPGTTTTS TGPCKTCTTP AQGNSMFPSC 

       310        320        330        340        350        360 
CCTKTSDGNC TCIPIPSSWA FAKYLWEWAS VRFSWLSLLV PFVQWFVGLS PTVWLSAIWM 

       370        380 
MWYWGPSLYS ILSPFLPLLP IFFCLWVYI

« Hide

Isoform S (Small envelope protein) (SHB) (S-HBsAg) [UniParc].

Checksum: 12A0B859465C37CE
Show »

FASTA22625,416

References

[1]"Sequence 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.
Submitted (MAR-1992) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]"Functions of the large hepatitis B virus surface protein in viral particle morphogenesis."
Bruss V., Gerhardt E., Vieluf K., Wunderlich G.
Intervirology 39:23-31(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.
[3]"Role of glycan processing in hepatitis B virus envelope protein trafficking."
Block T.M., Lu X., Mehta A., Park J., Blumberg B.S., Dwek R.
Adv. Exp. Med. Biol. 435:207-216(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.
[4]"Envelopment of the hepatitis B virus nucleocapsid."
Bruss V.
Virus Res. 106:199-209(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.
[5]"Hepatitis B virus pre-S mutants, endoplasmic reticulum stress and hepatocarcinogenesis."
Wang H.C., Huang W., Lai M.D., Su I.J.
Cancer Sci. 97:683-688(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.

Web resources

HepSEQ

Hepatitis virus B database

Cross-references

Sequence databases

EMBL
GenBank
DDBJ		X65258 Genomic DNA. Translation: CAA46353.1.
PIRJQ2054.
S20749.

3D structure databases

ModBaseSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Family and domain databases

InterProIPR000349. Hepvir_surfAg.
[Graphical view]
PfamPF00695. vMSA. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameHBSAG_HBVD6
AccessionPrimary (citable) accession number: Q67875
Entry history
Integrated into UniProtKB/Swiss-Prot: February 26, 2008
Last sequence update: November 1, 1996
Last modified: January 9, 2013
This is version 54 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

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