Complement C9 (C9) Active Protein

This gene encodes the final component of the complement system. It participates in the formation of the Membrane Attack Complex (MAC). The MAC assembles on bacterial membranes to form a pore, permitting disruption of bacterial membrane organization. Mutations in this gene cause component C9 deficiency. [provided by RefSeq, Feb 2009]

C9: Constituent of the membrane attack complex (MAC) that plays a key role in the innate and adaptive immune response by forming pores in the plasma membrane of target cells. C9 is the pore-forming subunit of the MAC. Defects in C9 are a cause of complement component 9 deficiency (C9D). A rare defect of the complement classical pathway associated with susceptibility to severe recurrent infections, predominantly by Neisseria gonorrhoeae or Neisseria meningitidis. Belongs to the complement C6/C7/C8/C9 family.

Protein type: Membrane protein, multi-pass; Membrane protein, integral; Apoptosis; Extracellular matrix

Chromosomal Location of Human Ortholog: 5p14-p12

Cellular Component: membrane attack complex; integral to plasma membrane; cytoplasm; extracellular region; plasma membrane

Biological Process: complement activation, alternative pathway; regulation of complement activation; innate immune response; hemolysis by symbiont of host red blood cells; complement activation, classical pathway

Disease: Macular Degeneration, Age-related, 15; Complement Component 9 Deficiency