C3
C3 (complement C3, previously complement component 3; aliases CPAMD1, ARMD9, C3a and C3b) is a secreted protein that plays a central role in activation of the complement system. Its peptide products include the C3a anaphylatoxin, which modulates inflammation. Browse Assay Genie's current range of C3 research reagents below, or read on for the biology behind the target.
C3 plays a central role in the activation of the complement system, and its activation is required for both the classical and the alternative complement pathways. The encoded preproprotein is proteolytically processed into alpha and beta subunits, which together form the mature protein. This is then cleaved further to generate numerous peptide products, including those known as C3a and C3b. The C3a peptide, also called the C3a anaphylatoxin, modulates inflammation and possesses antimicrobial activity. UniProt also annotates C3 as acting as a chemoattractant for neutrophils in chronic inflammation.
The C3 gene encodes complement C3, which UniProt lists as secreted and present at the cell surface. HGNC places it in the gene groups for receptor ligands, C3 and PZP like alpha-2-macroglobulin domain containing proteins, and complement system activation components. Mouse and rat both carry a C3 ortholog, so the protein can be studied across common model species.
The protein was previously named complement component 3, and the aliases CPAMD1 and ARMD9 also appear in the literature. Mutations in the C3 gene are associated with atypical haemolytic uraemic syndrome and age-related macular degeneration in human patients, which makes C3 a frequent subject in studies of complement dysregulation. Researchers measuring C3 may work with the intact protein or with its processed fragments, so it is worth checking which form a given C3 antibody or C3 ELISA kit recognises.
C3 is required for both classical and alternative complement activation, so it is a core readout when studying how the pathways are triggered.
The C3a anaphylatoxin modulates inflammation, and C3 is annotated as a neutrophil chemoattractant in chronic inflammation.
The C3a peptide possesses antimicrobial activity, linking C3 processing to innate defence mechanisms.
C3 mutations are associated with atypical haemolytic uraemic syndrome and age-related macular degeneration in human patients.
C3 plays a central role in activating the complement system and is required for both the classical and alternative pathways. It is processed into several peptides, including C3a, an anaphylatoxin that modulates inflammation and has antimicrobial activity. UniProt also notes a role as a neutrophil chemoattractant in chronic inflammation.
The preproprotein is cleaved into alpha and beta subunits and then into many peptide products, so names such as C3a and C3b refer to processed fragments. CPAMD1 and ARMD9 are aliases of the gene, and complement component 3 is its previous HGNC name.
Mouse and rat each have a C3 ortholog. In humans, mutations in the C3 gene are associated with atypical haemolytic uraemic syndrome and age-related macular degeneration. Check the datasheet of any product for its validated reactivity.
Other complement system components, anaphylatoxins and regulators that sit alongside C3 in complement activation.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P01024; product specifications from Assay Genie datasheets.