Complement C1s
MESHD003173
A 77-kDa subcomponent of complement C1, encoded by gene C1S, is a SERINE PROTEASE existing as a proenzyme (homodimer) in the intact complement C1 complex. Upon the binding of COMPLEMENT C1Q to antibodies, the activated COMPLEMENT C1R cleaves C1s into two chains, A (heavy) and B (light, the serine protease), linked by disulfide bonds yielding the active C1s. The activated C1s, in turn, cleaves COMPLEMENT C2 and COMPLEMENT C4 to form C4b2a (CLASSICAL C3 CONVERTASE).
Synonyms
- C1s, Complement
- Complement 1s
- C 1 Esterase
- Esterase, C 1
- Complement 1 Esterase
- Esterase, Complement 1
- Complement Component 1s
- Component 1s, Complement
- C1s Complement
- Complement, C1s
- C1 Esterase
- Esterase, C1
Source last updated 2026-05-24T15:27:57.172Z