Publication Abstract from PubMed
Protein C inhibitor (PCI) is a member of the serpin family that has many biological functions. In blood it acts as a procoagulant, and, in the seminal vesicles, it is required for spermatogenesis. The activity of PCI is affected by heparin binding in a manner unique among the heparin binding serpins, and, in addition, PCI binds hydrophobic hormones with apparent specificity for retinoids. Here we present the 2.4 A crystallographic structure of reactive center loop (RCL) cleaved PCI. A striking feature of the structure is a two-turn N-terminal shortening of helix A, which creates a large hydrophobic pocket that docking studies indicate to be the retinoid binding site. On the basis of surface electrostatic properties, a novel mechanism for heparin activation is proposed.
Crystal structure of protein C inhibitor provides insights into hormone binding and heparin activation.,Huntington JA, Kjellberg M, Stenflo J Structure. 2003 Feb;11(2):205-15. PMID:12575940[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
