Contents

Search

complement C1q

Function: - C1q associates with the proenzymes C1r & C1s to yield C1, the first component of the complement cascade - the collagen-like regions of C1q interact with the Ca+2-dependent C1r(2)C1s(2) proenzyme complex, & 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 Structure: - C1q is composed of 9 subunits, 6 of which are disulfide- linked dimers of C1QA & C1QB, & 3 of which are disulfide- linked dimers of C1QC

Interactions

molecular events

General

complement molecular complex

Properties

COMPARTMENT: plasma SUBUNITS: complement C1q triplet (6)

Database Correlations

OMIM 120570

References

  1. UniProt :accession P02745
  2. OMIM :accession 120570

Component-of

molecular complex

Components

complement C1q triplet complement C1q-alpha chain (complement C1q subunit A, C1QA) complement C1q-beta chain (complement C1q subunit B, C1QB) complement C1q-gamma chain (complement C1q subunit C, C1QC)