C4b-binding protein alpha chain - P04003 (C4BPA_HUMAN)


Protein Feature View of PDB entries mapped to a UniProtKB sequence  

  • Number of PDB entries for P04003: 2
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. (data source: UniProt  )
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. (data source: UniProt  )
Organism (common name): Human
Other Gene names: C4BP
Chromosome Location: chr1:207286370- 207318062
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Data in green originates from UniProtKB  
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Data in lilac represent the genomic exon structure projected onto the UniProt sequence.
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  • Secstruc: Secondary structure projected from representative PDB entries onto the UniProt sequence.
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The PDB to UniProt mapping is based on the data provided by the EBI SIFTS project. See also Velankar et al., Nucleic Acids Research 33, D262-265 (2005).
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