NameComplement C1q subcomponent subunit A
Synonyms
  • Complement C1q subcomponent subunit A precursor
Gene NameC1QA
OrganismHuman
Amino acid sequence
>lcl|BSEQ0016678|Complement C1q subcomponent subunit A
MEGPRGWLVLCVLAISLASMVTEDLCRAPDGKKGEAGRPGRRGRPGLKGEQGEPGAPGIR
TGIQGLKGDQGEPGPSGNPGKVGYPGPSGPLGARGIPGIKGTKGSPGNIKDQPRPAFSAI
RRNPPMGGNVVIFDTVITNQEEPYQNHSGRFVCTVPGYYYFTFQVLSQWEICLSIVSSSR
GQVRRSLGFCDTTNKGLFQVVSGGMVLQLQQGDQVWVEKDPKKGHIYQGSEADSVFSGFL
IFPSA
Number of residues245
Molecular Weight26016.47
Theoretical pI9.45
GO Classification
Processes
  • innate immune response
  • complement activation, classical pathway
  • complement activation
  • cell-cell signaling
Components
  • collagen trimer
  • complement component C1 complex
  • extracellular region
  • extracellular exosome
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 ID4894854
UniProtKB IDP02745
UniProtKB Entry NameC1QA_HUMAN
Cellular LocationSecreted
Gene sequence
>lcl|BSEQ0016679|Complement C1q subcomponent subunit A (C1QA)
ATGGAGGGTCCCCGGGGATGGCTGGTGCTCTGTGTGCTGGCCATATCGCTGGCCTCTATG
GTGACCGAGGACTTGTGCCGAGCACCAGACGGGAAGAAAGGGGAGGCAGGAAGACCTGGC
AGACGGGGGCGGCCAGGCCTCAAGGGGGAGCAAGGGGAGCCGGGGGCCCCTGGCATCCGG
ACAGGCATCCAAGGCCTTAAAGGAGACCAGGGGGAACCTGGGCCCTCTGGAAACCCCGGC
AAGGTGGGCTACCCAGGGCCCAGCGGCCCCCTCGGAGCCCGTGGCATCCCGGGAATTAAA
GGCACCAAGGGCAGCCCAGGAAACATCAAGGACCAGCCGAGGCCAGCCTTCTCCGCCATT
CGGCGGAACCCCCCAATGGGGGGCAACGTGGTCATCTTCGACACGGTCATCACCAACCAG
GAAGAACCGTACCAGAACCACTCCGGCCGATTCGTCTGCACTGTACCCGGCTACTACTAC
TTCACCTTCCAGGTGCTGTCCCAGTGGGAAATCTGCCTGTCCATCGTCTCCTCCTCAAGG
GGCCAGGTCCGACGCTCCCTGGGCTTCTGTGACACCACCAACAAGGGGCTCTTCCAGGTG
GTGTCAGGGGGCATGGTGCTTCAGCTGCAGCAGGGTGACCAGGTCTGGGTTGAAAAAGAC
CCCAAAAAGGGTCACATTTACCAGGGCTCTGAGGCCGACAGCGTCTTCAGCGGCTTCCTC
ATCTTCCCATCTGCCTGA
GenBank Gene IDAF135157
GeneCard IDNot Available
GenAtlas IDC1QA
HGNC IDHGNC:1241
Chromosome Location1
Locus1p36.12
References
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