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Identification of surface epitopes of human coagulation factor Va that are important for interaction with activated protein C and heparin

Segers, Kenneth; Dahlbäck, Björn LU ; Rosing, Jan and Nicolaes, Gerry A. F. (2008) In Journal of Biological Chemistry 283(33). p.22573-22581
Abstract
Inactivation of factor Va (FVa) by activated protein C (APC) is a key reaction in the down- regulation of thrombin formation. FVa inactivation by APC is correlated with a loss of FXa cofactor activity as a result of three proteolytic cleavages in the FVa heavy chain at Arg(306), Arg(506), and Arg(679). Recently, we have shown that heparin specifically inhibits the APC- mediated cleavage at Arg(506) and stimulates cleavage at Arg(306). Three- dimensional molecular models of APC docked at the Arg(306) and Arg(506) cleavage sites in FVa have identified several FVa amino acids that may be important for FVa inactivation by APC in the absence and presence of heparin. Mutagenesis of Lys(320), Arg(321), and Arg(400) to Ala resulted in an increased... (More)
Inactivation of factor Va (FVa) by activated protein C (APC) is a key reaction in the down- regulation of thrombin formation. FVa inactivation by APC is correlated with a loss of FXa cofactor activity as a result of three proteolytic cleavages in the FVa heavy chain at Arg(306), Arg(506), and Arg(679). Recently, we have shown that heparin specifically inhibits the APC- mediated cleavage at Arg(506) and stimulates cleavage at Arg(306). Three- dimensional molecular models of APC docked at the Arg(306) and Arg(506) cleavage sites in FVa have identified several FVa amino acids that may be important for FVa inactivation by APC in the absence and presence of heparin. Mutagenesis of Lys(320), Arg(321), and Arg(400) to Ala resulted in an increased inactivation rate by APC at Arg(306), which indicates the importance of these residues in the FVa- APC interaction. No heparin- mediated stimulation of Arg(306) cleavage was observed for these mutants, and stimulation by protein S was similar to that of wild type FVa. With this, we have now demonstrated that a cluster of basic residues in FVa comprising Lys(320), Arg(321), and Arg(400) is required for the heparin-mediated stimulation of cleavage at Arg(306) by APC. Furthermore, mutations that were introduced near the Arg(506) cleavage site had a significant but modest effect on the rate of APC- catalyzed FVa inactivation, suggesting an extended interaction surface between the FVa Arg(506) site and APC. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
283
issue
33
pages
22573 - 22581
publisher
ASBMB
external identifiers
  • wos:000258321000026
  • scopus:53049089511
ISSN
1083-351X
DOI
10.1074/jbc.M801724200
language
English
LU publication?
yes
id
97b2ad01-0daa-44ee-ac6e-dc2927708207 (old id 1253381)
date added to LUP
2008-10-30 11:19:00
date last changed
2017-01-01 04:49:35
@article{97b2ad01-0daa-44ee-ac6e-dc2927708207,
  abstract     = {Inactivation of factor Va (FVa) by activated protein C (APC) is a key reaction in the down- regulation of thrombin formation. FVa inactivation by APC is correlated with a loss of FXa cofactor activity as a result of three proteolytic cleavages in the FVa heavy chain at Arg(306), Arg(506), and Arg(679). Recently, we have shown that heparin specifically inhibits the APC- mediated cleavage at Arg(506) and stimulates cleavage at Arg(306). Three- dimensional molecular models of APC docked at the Arg(306) and Arg(506) cleavage sites in FVa have identified several FVa amino acids that may be important for FVa inactivation by APC in the absence and presence of heparin. Mutagenesis of Lys(320), Arg(321), and Arg(400) to Ala resulted in an increased inactivation rate by APC at Arg(306), which indicates the importance of these residues in the FVa- APC interaction. No heparin- mediated stimulation of Arg(306) cleavage was observed for these mutants, and stimulation by protein S was similar to that of wild type FVa. With this, we have now demonstrated that a cluster of basic residues in FVa comprising Lys(320), Arg(321), and Arg(400) is required for the heparin-mediated stimulation of cleavage at Arg(306) by APC. Furthermore, mutations that were introduced near the Arg(506) cleavage site had a significant but modest effect on the rate of APC- catalyzed FVa inactivation, suggesting an extended interaction surface between the FVa Arg(506) site and APC.},
  author       = {Segers, Kenneth and Dahlbäck, Björn and Rosing, Jan and Nicolaes, Gerry A. F.},
  issn         = {1083-351X},
  language     = {eng},
  number       = {33},
  pages        = {22573--22581},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {Identification of surface epitopes of human coagulation factor Va that are important for interaction with activated protein C and heparin},
  url          = {http://dx.doi.org/10.1074/jbc.M801724200},
  volume       = {283},
  year         = {2008},
}