Names & Taxonomy

Uniprot ID:
P04003
Entry Name:
C4BPA_HUMAN
Status:
reviewed
Protein Names:
C4b-binding protein alpha chain (C4bp) (Proline-rich protein) (PRP)
Gene Names:
C4BPA C4BP
Gene Names Primary:
C4BPA
Organism:
Homo sapiens (Human)

Structure

Length:
597
Sequence:
MHPPKTPSGALHRKRKMAAWPFSRLWKVSDPILFQMTLIAALLPAVLGNCGPPPTLSFAAPMDITLTETRFKTGTTLKYTCLPGYVRSHSTQTLTCNSDGEWVYNTFCIYKRCRHPGELRNGQVEIKTDLSFGSQIEFSCSEGFFLIGSTTSRCEVQDRGVGWSHPLPQCEIVKCKPPPDIRNGRHSGEENFYAYGFSVTYSCDPRFSLLGHASISCTVENETIGVWRPSPPTCEKITCRKPDVSHGEMVSGFGPIYNYKDTIVFKCQKGFVLRGSSVIHCDADSKWNPSPPACEPNSCINLPDIPHASWETYPRPTKEDVYVVGTVLRYRCHPGYKPTTDEPTTVICQKNLRWTPYQGCEALCCPEPKLNNGEITQHRKSRPANHCVYFYGDEISFSCHETSRFSAICQGDGTWSPRTPSCGDICNFPPKIAHGHYKQSSSYSFFKEEIIYECDKGYILVGQAKLSCSYSHWSAPAPQCKALCRKPELVNGRLSVDKDQYVEPENVTIQCDSGYGVVGPQSITCSGNRTWYPEVPKCEWETPEGCEQVLTGKRLMQCLPNPEDVKMALEVYKLSLEIEQLELQRDSARQSTLDKEL
Proteomes:
UP000005640

Subcellular location

Subcellular Location:
Secreted.

Function

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. Alpha chain binds C4b. It interacts also with anticoagulant protein S and with serum amyloid P component.
Gene Ontology Go:
blood microparticle
extracellular region
extracellular space
other organism cell
plasma membrane
poly(A) RNA binding
complement activation, classical pathway
innate immune response
negative regulation of complement activation, classical pathway
positive regulation of protein catabolic process
regulation of complement activation
regulation of opsonization
Gene Ontology Biological Process:
complement activation, classical pathway
innate immune response
negative regulation of complement activation, classical pathway
positive regulation of protein catabolic process
regulation of complement activation
regulation of opsonization
Gene Ontology Molecular Function:
poly(A) RNA binding
Gene Ontology Cellular Component:
blood microparticle
extracellular region
extracellular space
other organism cell
plasma membrane
Keywords:
3D-structure
Complement pathway
Complete proteome
Direct protein sequencing
Disulfide bond
Glycoprotein
Immunity
Innate immunity
Polymorphism
Reference proteome
Repeat
Secreted
Signal
Sushi
Interacts With:
P13050

Publication

PubMed ID:
2590215 1989602 14702039 15489334 3378624 3017751 3840370 4033666 14760718 16335952 19159218 24275569 6222381 16330538