SEARCH:   Advanced

Blood, 1 May 2004, Vol. 103, No. 9, pp. 3381-3387. Prepublished online as a Blood First Edition Paper on December 24, 2003; DOI 10.1182/blood-2003-06-2092. This Article Full Text (PDF) All Versions of this Article: 2003-06-2092v1 103/9/3381    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Steen, M. Articles by Dahlback, B. Search for Related Content PubMed PubMed Citation Articles by Steen, M. Articles by Dahlback, B. Social Bookmarking                   What's this? Submitted June 27, 2003 Accepted December 10, 2003 Functional characterization of Factor V-Ile359Thr, a novel mutation associated with thrombosis Marten Steen, Eva A Norstrom, Ann-Louise Tholander, Paula H B Bolton-Maggs, Andrew Mumford, John H McVey, Edward G D Tuddenham, and Bjorn Dahlback* Department of Laboratory Medicine, Lund University, Malmo, Sweden Department of Clinical Haematology, Manchester Haemophilia Comprehensive Care Centre, Manchester, United Kingdom Haemostasis and Thrombosis, MRC Clinical Sciences Centre, Imperial College, London, United Kingdom Department of Haematology, Bristol Royal Infirmary, Bristol, United Kingdom * Corresponding author; email: bjorn.dahlback{at}klkemi.mas.lu.se. A missense mutation, FV-Ile359Thr (FV Liverpool), associated with thrombosis has recently been described. This mutation creates an additional potential N-linked glycosylation site (Asn-X-Ser/Thr) in factor V (FV) at Asn357 that could interfere with secretion and/or protein interactions. To investigate the molecular pathology of FV-Ile359Thr, the mutation was created by site-directed mutagenesis and expressed, together with other mutations that could help explain the phenotype (FV-Arg306Gln/Ile359Thr/Arg679Gln, FV-Ile359Thr/Arg506Gln/Arg679Gln and FV-Asn357Gln/Ile359Thr). The FV-Ile359Thr was secreted normally and had full procoagulant activity. Western-blot-analysis showed that FV-Ile359Thr migrated slower, while the FV-Asn357Gln/Ile359Thr was indistinguishable from FV-wild type (WT), indicating that FV-Ile359Thr was expressed with an additional carbohydrate chain. APC-mediated inactivation in a FVa degradation assay showed that the Ile359Thr mutation significantly reduced the cleavage at Arg306 both in the presence and absence of protein S, whereas the cleavage at Arg506 was unaffected. When tested in an FVIIIa degradation assay, the FV-Ile359Thr variant exhibited equally low APC-cofactor activity as FV Leiden (FV-Arg506Gln). In conclusion, the Ile359Thr mutation appears to affect anticoagulation by two mechanisms, impeding the APC-mediated down regulation of the FVa molecule, and additionally being a poor APC cofactor for the down regulation of FVIIIa. These findings explain the association of the FV-Ile359Thr mutation with thrombosis. CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? This article has been cited by other articles: B. Dahlback Anticoagulant factor V and thrombosis risk Blood, June 1, 2004; 103(11): 3995 - 3995. [Full Text] [PDF]

	Copyright © 2003 by American Society of Hematology         Online ISSN: 1528-0020