NLM Logo

Complement C1q MeSH Descriptor Data 2025


MeSH Heading
Complement C1q
Tree Number(s)
D12.776.124.486.274.050.270
Unique ID
D015922
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D015922
Scope Note
A subcomponent of complement C1, composed of six copies of three polypeptide chains (A, B, and C), each encoded by a separate gene (C1QA; C1QB; C1QC). This complex is arranged in nine subunits (six disulfide-linked dimers of A and B, and three disulfide-linked homodimers of C). C1q has binding sites for antibodies (the heavy chain of IMMUNOGLOBULIN G or IMMUNOGLOBULIN M). The interaction of C1q and immunoglobulin activates the two proenzymes COMPLEMENT C1R and COMPLEMENT C1S, thus initiating the cascade of COMPLEMENT ACTIVATION via the CLASSICAL COMPLEMENT PATHWAY.
Entry Term(s)
C1q Complement
Complement 1q
Complement Component 1q
Pharm Action
Immunologic Factors
Registry Numbers
80295-33-6
CAS Type 1 Name
Complement C1q
Previous Indexing
Complement 1 (1980-1989)
Complement Activating Enzymes (1979-1989)
Public MeSH Note
2006; see COMPLEMENT 1Q 1990-2005
History Note
2006 (1990)
Date Established
1990/01/01
Date of Entry
1989/05/25
Revision Date
2005/06/30
Complement C1q Preferred
page delivered in 0.172s