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P20851 (C4BPB_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 127. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (5) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Web links·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
C4b-binding protein beta chain
Gene names
Name:C4BPB
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length252 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Controls the classical pathway of complement activation. It binds as a cofactor to C3b/C4b inactivator (C3bINA), which then hydrolyzes the complement fragment C4b. It also accelerates the degradation of the C4bC2a complex (C3 convertase) by dissociating the complement fragment C2a. It also interacts with anticoagulant protein S and with serum amyloid P component. The beta chain binds protein S.

Subunit structure

Disulfide-linked complex of alpha and beta chains of 3 possible sorts: a 570 kDa complex of 7 alpha chains and 1 beta chain, a 530 kDa homoheptamer of alpha chains or a 500 kDa complex of 6 alpha chains and 1 beta chain. The central body of the alpha chain homopolymer supports tentacles, each with the binding site for C4b at the end.

Subcellular location

Secreted.

Sequence similarities

Contains 3 Sushi (CCP/SCR) domains.

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]
Isoform 1 (identifier: P20851-1)

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 2 (identifier: P20851-2)

The sequence of this isoform differs from the canonical sequence as follows:
     20-20: Missing.
Note: No experimental confirmation available.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 1717
Chain18 – 252235C4b-binding protein beta chain
PRO_0000005892

Regions

Domain21 – 7858Sushi 1
Domain79 – 13658Sushi 2
Domain137 – 19357Sushi 3

Amino acid modifications

Glycosylation641N-linked (GlcNAc...) Ref.7 Ref.8
Glycosylation711N-linked (GlcNAc...) Ref.7
Glycosylation981N-linked (GlcNAc...) Ref.7 Ref.8 Ref.9
Glycosylation1171N-linked (GlcNAc...) Potential
Glycosylation1541N-linked (GlcNAc...) Potential
Disulfide bond23 ↔ 63 By similarity
Disulfide bond49 ↔ 76 By similarity
Disulfide bond81 ↔ 121 By similarity
Disulfide bond107 ↔ 134 By similarity
Disulfide bond139 ↔ 179 By similarity
Disulfide bond165 ↔ 191 By similarity
Disulfide bond202Interchain (with alpha chain) Potential
Disulfide bond216Interchain (with alpha chain) Potential

Natural variations

Alternative sequence201Missing in isoform 2.
VSP_022594
Natural variant1021K → Q. Ref.3
Corresponds to variant rs56258224 [ dbSNP | Ensembl ].
VAR_038734
Natural variant1981P → S.
Corresponds to variant rs1803226 [ dbSNP | Ensembl ].
VAR_012039

Sequences

Sequence LengthMass (Da)Tools
Isoform 1 [UniParc].

Last modified February 1, 1991. Version 1.
Checksum: 0F6CC64067C5E2E7

FASTA25228,357
        10         20         30         40         50         60 
MFFWCACCLM VAWRVSASDA EHCPELPPVD NSIFVAKEVE GQILGTYVCI KGYHLVGKKT 

        70         80         90        100        110        120 
LFCNASKEWD NTTTECRLGH CPDPVLVNGE FSSSGPVNVS DKITFMCNDH YILKGSNRSQ 

       130        140        150        160        170        180 
CLEDHTWAPP FPICKSRDCD PPGNPVHGYF EGNNFTLGST ISYYCEDRYY LVGVQEQQCV 

       190        200        210        220        230        240 
DGEWSSALPV CKLIQEAPKP ECEKALLAFQ ESKNLCEAME NFMQQLKESG MTMEELKYSL 

       250 
ELKKAELKAK LL 

« Hide

Isoform 2 [UniParc].

Checksum: 2BA0722033999AF4
Show »

FASTA25128,286

References

« Hide 'large scale' references
[1]"The human C4b-binding protein beta-chain gene."
Hillarp A., Pardo-Manuel F., Ruiz R., de Cordoba S., Dahlback B.
J. Biol. Chem. 268:15017-15023(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[2]"Cloning of cDNA coding for the beta chain of human complement component C4b-binding protein: sequence homology with the alpha chain."
Hillarp A., Dahlback B.
Proc. Natl. Acad. Sci. U.S.A. 87:1183-1187(1990) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[3]SeattleSNPs variation discovery resource
Submitted (MAY-2007) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], VARIANT GLN-102.
[4]"The DNA sequence and biological annotation of human chromosome 1."
Gregory S.G., Barlow K.F., McLay K.E., Kaul R., Swarbreck D., Dunham A., Scott C.E., Howe K.L., Woodfine K., Spencer C.C.A., Jones M.C., Gillson C., Searle S., Zhou Y., Kokocinski F., McDonald L., Evans R., Phillips K. expand/collapse author list , Atkinson A., Cooper R., Jones C., Hall R.E., Andrews T.D., Lloyd C., Ainscough R., Almeida J.P., Ambrose K.D., Anderson F., Andrew R.W., Ashwell R.I.S., Aubin K., Babbage A.K., Bagguley C.L., Bailey J., Beasley H., Bethel G., Bird C.P., Bray-Allen S., Brown J.Y., Brown A.J., Buckley D., Burton J., Bye J., Carder C., Chapman J.C., Clark S.Y., Clarke G., Clee C., Cobley V., Collier R.E., Corby N., Coville G.J., Davies J., Deadman R., Dunn M., Earthrowl M., Ellington A.G., Errington H., Frankish A., Frankland J., French L., Garner P., Garnett J., Gay L., Ghori M.R.J., Gibson R., Gilby L.M., Gillett W., Glithero R.J., Grafham D.V., Griffiths C., Griffiths-Jones S., Grocock R., Hammond S., Harrison E.S.I., Hart E., Haugen E., Heath P.D., Holmes S., Holt K., Howden P.J., Hunt A.R., Hunt S.E., Hunter G., Isherwood J., James R., Johnson C., Johnson D., Joy A., Kay M., Kershaw J.K., Kibukawa M., Kimberley A.M., King A., Knights A.J., Lad H., Laird G., Lawlor S., Leongamornlert D.A., Lloyd D.M., Loveland J., Lovell J., Lush M.J., Lyne R., Martin S., Mashreghi-Mohammadi M., Matthews L., Matthews N.S.W., McLaren S., Milne S., Mistry S., Moore M.J.F., Nickerson T., O'Dell C.N., Oliver K., Palmeiri A., Palmer S.A., Parker A., Patel D., Pearce A.V., Peck A.I., Pelan S., Phelps K., Phillimore B.J., Plumb R., Rajan J., Raymond C., Rouse G., Saenphimmachak C., Sehra H.K., Sheridan E., Shownkeen R., Sims S., Skuce C.D., Smith M., Steward C., Subramanian S., Sycamore N., Tracey A., Tromans A., Van Helmond Z., Wall M., Wallis J.M., White S., Whitehead S.L., Wilkinson J.E., Willey D.L., Williams H., Wilming L., Wray P.W., Wu Z., Coulson A., Vaudin M., Sulston J.E., Durbin R.M., Hubbard T., Wooster R., Dunham I., Carter N.P., McVean G., Ross M.T., Harrow J., Olson M.V., Beck S., Rogers J., Bentley D.R.
Nature 441:315-321(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[5]Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. expand/collapse author list , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C.
Submitted (SEP-2005) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
Tissue: Skeletal muscle.
[7]"Screening for N-glycosylated proteins by liquid chromatography mass spectrometry."
Bunkenborg J., Pilch B.J., Podtelejnikov A.V., Wisniewski J.R.
Proteomics 4:454-465(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-64; ASN-71 AND ASN-98.
Tissue: Plasma.
[8]"Human plasma N-glycoproteome analysis by immunoaffinity subtraction, hydrazide chemistry, and mass spectrometry."
Liu T., Qian W.-J., Gritsenko M.A., Camp D.G. II, Monroe M.E., Moore R.J., Smith R.D.
J. Proteome Res. 4:2070-2080(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-64 AND ASN-98.
Tissue: Plasma.
[9]"Glycoproteomics analysis of human liver tissue by combination of multiple enzyme digestion and hydrazide chemistry."
Chen R., Jiang X., Sun D., Han G., Wang F., Ye M., Wang L., Zou H.
J. Proteome Res. 8:651-661(2009) [PubMed] [Europe PMC] [Abstract]
Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-98.
Tissue: Liver.
+Additional computationally mapped references.

Web resources

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
L11244 mRNA. Translation: AAA35615.1.
L11245 mRNA. Translation: AAA35616.1.
M29964 mRNA. Translation: AAB59520.1.
EF613556 Genomic DNA. Translation: ABQ52216.1.
AL445493 Genomic DNA. Translation: CAH70780.1.
AL445493 Genomic DNA. Translation: CAH70781.1.
CH471100 Genomic DNA. Translation: EAW93504.1.
CH471100 Genomic DNA. Translation: EAW93506.1.
BC005378 mRNA. Translation: AAH05378.1.
PIRA34877. A47107.
RefSeqNP_000707.1. NM_000716.3.
NP_001017364.1. NM_001017364.1.
NP_001017365.1. NM_001017365.1.
NP_001017366.1. NM_001017366.1.
NP_001017367.1. NM_001017367.1.
XP_005273310.1. XM_005273253.2.
XP_005273311.1. XM_005273254.2.
UniGeneHs.99886.

3D structure databases

ProteinModelPortalP20851.
SMRP20851. Positions 4-234.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid107186. 1 interaction.
STRING9606.ENSP00000243611.

Polymorphism databases

DMDM115213.

Proteomic databases

PaxDbP20851.
PRIDEP20851.

Protocols and materials databases

DNASU725.
StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000243611; ENSP00000243611; ENSG00000123843. [P20851-1]
ENST00000367076; ENSP00000356043; ENSG00000123843. [P20851-2]
ENST00000367078; ENSP00000356045; ENSG00000123843. [P20851-1]
ENST00000391923; ENSP00000375790; ENSG00000123843. [P20851-1]
GeneID725.
KEGGhsa:725.
UCSCuc001hfi.3. human. [P20851-2]
uc001hfj.3. human. [P20851-1]

Organism-specific databases

CTD725.
GeneCardsGC01P207262.
HGNCHGNC:1328. C4BPB.
HPAHPA051620.
MIM120831. gene.
neXtProtNX_P20851.
PharmGKBPA25908.
GenAtlasSearch...

Phylogenomic databases

eggNOGNOG260856.
HOGENOMHOG000032571.
HOVERGENHBG004922.
InParanoidP20851.
KOK04003.
OMAILKGSNW.
OrthoDBEOG7QRQVH.
PhylomeDBP20851.
TreeFamTF342864.

Enzyme and pathway databases

ReactomeREACT_6900. Immune System.

Gene expression databases

ArrayExpressP20851.
BgeeP20851.
CleanExHS_C4BPB.
GenevestigatorP20851.

Family and domain databases

InterProIPR000436. Sushi_SCR_CCP.
[Graphical view]
PfamPF00084. Sushi. 3 hits.
[Graphical view]
SMARTSM00032. CCP. 3 hits.
[Graphical view]
SUPFAMSSF57535. SSF57535. 3 hits.
PROSITEPS50923. SUSHI. 3 hits.
[Graphical view]
ProtoNetSearch...

Other

GenomeRNAi725.
NextBio2944.
PROP20851.
SOURCESearch...

Entry information

Entry nameC4BPB_HUMAN
AccessionPrimary (citable) accession number: P20851
Secondary accession number(s): A5JYP8 expand/collapse secondary AC list , D3DT81, Q5VVR0, Q9BS25
Entry history
Integrated into UniProtKB/Swiss-Prot: February 1, 1991
Last sequence update: February 1, 1991
Last modified: April 16, 2014
This is version 127 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

SIMILARITY comments

Index of protein domains and families

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human chromosome 1

Human chromosome 1: entries, gene names and cross-references to MIM