NameComplement C1q subcomponent subunit B
Synonyms
  • Complement C1q subcomponent subunit B precursor
Gene NameC1QB
OrganismHuman
Amino acid sequence
>lcl|BSEQ0016676|Complement C1q subcomponent subunit B
MMMKIPWGSIPVLMLLLLLGLIDISQAQLSCTGPPAIPGIPGIPGTPGPDGQPGTPGIKG
EKGLPGLAGDHGEFGEKGDPGIPGNPGKVGPKGPMGPKGGPGAPGAPGPKGESGDYKATQ
KIAFSATRTINVPLRRDQTIRFDHVITNMNNNYEPRSGKFTCKVPGLYYFTYHASSRGNL
CVNLMRGRERAQKVVTFCDYAYNTFQVTTGGMVLKLEQGENVFLQATDKNSLLGMEGANS
IFSGFLLFPDMEA
Number of residues253
Molecular Weight26721.62
Theoretical pI8.87
GO Classification
Processes
  • complement activation
  • innate immune response
  • inner ear development
  • complement activation, classical pathway
Components
  • extracellular region
  • extracellular exosome
  • blood microparticle
  • collagen trimer
  • complement component C1 complex
General FunctionNot Available
Specific FunctionC1q associates with the proenzymes C1r and C1s to yield C1, the first component of the serum complement system. The collagen-like regions of C1q interact with the Ca(2+)-dependent C1r(2)C1s(2) proenzyme complex, and efficient activation of C1 takes place on interaction of the globular heads of C1q with the Fc regions of IgG or IgM antibody present in immune complexes.
Pfam Domain Function
Transmembrane RegionsNot Available
GenBank Protein ID573114
UniProtKB IDP02746
UniProtKB Entry NameC1QB_HUMAN
Cellular LocationSecreted
Gene sequence
>lcl|BSEQ0016677|Complement C1q subcomponent subunit B (C1QB)
ATGATGATGAAGATCCCATGGGGCAGCATCCCAGTACTGATGTTGCTCCTGCTCCTGGGC
CTAATCGATATCTCCCAGGCCCAGCTCAGCTGCACCGGGCCCCCAGCCATCCCTGGCATC
CCGGGTATCCCTGGGACACCTGGCCCCGATGGCCAACCTGGGACCCCAGGGATAAAAGGA
GAGAAAGGGCTTCCAGGGCTGGCTGGAGACCATGGTGAGTTCGGAGAGAAGGGAGACCCA
GGGATTCCTGGGAATCCAGGAAAAGTCGGCCCCAAGGGCCCCATGGGCCCTAAAGGTGGC
CCAGGGGCCCCTGGAGCCCCAGGCCCCAAAGGTGAATCGGGAGACTACAAGGCCACCCAG
AAAATCGCCTTCTCTGCCACAAGAACCATCAACGTCCCCCTGCGCCGGGACCAGACCATC
CGCTTCGACCACGTGATCACCAACATGAACAACAATTATGAGCCCCGCAGTGGCAAGTTC
ACCTGCAAGGTGCCCGGTCTCTACTACTTCACCTACCACGCCAGCTCTCGAGGGAACCTG
TGCGTGAACCTCATGCGTGGCCGGGAGCGTGCACAGAAGGTGGTCACCTTCTGTGACTAT
GCCTACAACACCTTCCAGGTCACCACCGGTGGCATGGTCCTCAAGCTGGAGCAGGGGGAG
AACGTCTTCCTGCAGGCCACCGACAAGAACTCACTACTGGGCATGGAGGGTGCCAACAGC
ATCTTTTCCGGGTTCCTGCTCTTTCCAGATATGGAGGCCTGA
GenBank Gene IDX03084
GeneCard IDNot Available
GenAtlas IDC1QB
HGNC IDHGNC:1242
Chromosome Location1
Locus1p36.12
References
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