Activation of C5 by a C5 convertase initiates the spontaneous assbly of the late complent components, C5-C9, into the mbrane attack complex. C5b has a transient binding site for C6. The C5b-C6 complex is the foundation upon which the lytic complex is assbled.Derived from proteolytic degradation of complent C5, C5 anaphylatoxin is a mediator of local inflammatory process. Binding to the receptor C5AR1 induces a variety of responses including intracellular calcium release, contraction of smooth muscle, increased vascular permeability, and histamine release from mast cells and basophilic leukocytes . C5a is also a potent chokine which stimulates the locomotion of polymorphonuclear leukocytes and directs their migration toward sites of inflammation.
Complete cDNA sequence of human complement pro-C5. Evidence of truncated transcripts derived from a single copy gene.Haviland D.L., Haviland J.C., Fleischer D.T., Hunt A., Wetsel R.A.J. Immunol. 146:362-368(1991)
Research Topic:Signal Transduction
