protein_function: Factor D cleaves factor B when the latter is complexedwith factor C3b, activating the C3bbb complex, which then becomesthe C3 convertase of the alternate pathway. Its function ishomologous to that of C1s in the classical pathway.
Complement factor D(CFD), also called ADIPSIN or FACTOR D, is a protein which in humans is encoded by the CFD gene. The protein encoded by this gene belongs to the trypsin family of peptidases. It is mapped to 19p13.3. The encoded protein is a component of the alternative complement pathway which is best known for its role in humoral suppression of infectious agents. This protein is also a serine protease that is secreted by adipocytes into the bloodstream. Finally, the encoded protein has a high level of expression in fat, suggesting a role for adipose tissue in immune system biology. What"s more, Factor D is a serine protease that stimulates glucose transport for triglyceride accumulation in fats cells and inhibits lipolysis.
