Complement Factor I (CFI) Antibody – Rabbit

This gene encodes a serine protease that plays an important role in the classical and alternative complement pathways where it cleaves C4b and C3b components of C3 and C5 convertases. The encoded preproprotein undergoes proteolytic processing to generate an active, disulfide-linked heterodimeric enzyme comprised of heavy and light chains. [provided by RefSeq, Jul 2016]

CFI: Responsible for cleaving the alpha-chains of C4b and C3b in the presence of the cofactors C4-binding protein and factor H respectively. Defects in CFI are a cause of susceptibility to hemolytic uremic syndrome atypical type 3 (AHUS3). An atypical form of hemolytic uremic syndrome. It is a complex genetic disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, renal failure and absence of episodes of enterocolitis and diarrhea. In contrast to typical hemolytic uremic syndrome, atypical forms have a poorer prognosis, with higher death rates and frequent progression to end-stage renal disease. Susceptibility to the development of atypical hemolytic uremic syndrome can be conferred by mutations in various components of or regulatory factors in the complement cascade system. Other genes may play a role in modifying the phenotype. Defects in CFI are the cause of complement factor I deficiency (CFI deficiency). CFI deficiency is an autosomal recessive condition associated with a propensity to pyogenic infections. Belongs to the peptidase S1 family.

Protein type: EC 3.4.21.45; Protease; Secreted; Secreted, signal peptide

Chromosomal Location of Human Ortholog: 3 G3|3 59.21 cM

Cellular Component: extracellular region; extracellular space; membrane; nucleus

Molecular Function: hydrolase activity; metal ion binding; peptidase activity; scavenger receptor activity; serine-type endopeptidase activity; serine-type peptidase activity

Biological Process: complement activation, classical pathway; immune system process; innate immune response; proteolysis