title: A plasma protein indistinguishable from ribosomal protein S19: conversion to a monocyte chemotactic factor by a factor XIIIa-catalyzed reaction on activated platelet membrane phosphatidylserine in association with blood coagulation.
abstract: A monocyte-chemoattracting factor is generated during blood coagulation and during clotting of platelet-rich plasma. This chemotactic factor attracts monocytes as a ligand of the C5a receptor; however, it inhibits C5a-induced neutrophil chemotaxis as an apparent receptor antagonist. The curious dual function of the serum monocyte chemotactic factor resembles that of the cross-linked homodimer of ribosomal protein S19 (RP S19). Indeed, the inactive precursor of the monocyte chemotactic factor was present in plasma, and the precursor molecule and RP S19, as well as the active form and the RP S19 dimer, were indistinguishable in terms of immunological reactivity and molecular size. Coagulation factor XIIIa, plasma transglutaminase, and membrane phosphatidylserine on the activated platelets were required for conversion of the precursor to the active form. In addition, the precursor molecule in plasma could be replaced by wild-type recombinant RP S19 but not by mutant forms of it. These results indicate that a molecule indistinguishable from RP S19 was present in plasma, and that the RP S19-like molecule was converted to the active form by a transglutaminase-catalyzed reaction on a scaffold that included the phosphatidylserine-exposed platelet membrane.
authors.affiliation: Department of Molecular Pathology, Faculty of Life Sciences, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811, Japan.
authors.forename: Umeko
authors.initials: U
authors.lastname: Semba
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Ota
authors.forename: Nan
authors.initials: N
authors.lastname: Jia
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Arima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishiura
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000042:Absorption; D017304:Annexin A5 / Q000378:metabolism; D000906:Antibodies; D055162:Biocatalysis; D001777:Blood Coagulation / Q000502:physiology*; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism*; D015936:Complement C5a / Q000378:metabolism; D026122:Factor XIIIa / Q000378:metabolism*; D006801:Humans; D018945:Monocyte Chemoattractant Proteins / Q000097:blood / Q000378:metabolism*; D050505:Mutant Proteins / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism*; D015539:Platelet Activation / Q000502:physiology*; D053657:Platelet-Rich Plasma / Q000378:metabolism; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000378:metabolism; D012269:Ribosomal Proteins / Q000097:blood / Q000378:metabolism*; D044967:Serum; D013997:Time Factors
chemical_list: D017304:Annexin A5; D000906:Antibodies; D018945:Monocyte Chemoattractant Proteins; D050505:Mutant Proteins; D010718:Phosphatidylserines; D011994:Recombinant Proteins; D012269:Ribosomal Proteins; C040343:ribosomal protein S19; D015936:Complement C5a; D026122:Factor XIIIa