Proteolytic Interactions of Factor IXa With Human Factor VI11 and Factor VIIIa
نویسنده
چکیده
Factor IXa was shown to inactivate both factor Vlll and factor Vllla in a phospholipid-dependent reaction that could be blocked by an antifactor IX antibody. Factor IXa-catalyzed inactivation correlated with proteolytic cleavages within the A1 subunit of factor Vllla and within the heavy chain (contiguous AI-A2-6 domains) of factor VIII. Furthermore, a relatively slow conversion of factor Vlll light chain to a 68-Kd fragment was observed after prolonged incubation. Sites of cleavage were identified within the A1 domain at Arg336Met337 and within the factor Vlll light chain at Arg1719Asn1720. Factor IXa failed to cleave isolated factor Vlll heavy chains, yet cleaved isolated factor Vlll light chain. In addition,
منابع مشابه
Proteolytic interactions of factor IXa with human factor VIII and factor VIIIa.
Factor IXa was shown to inactivate both factor VIII and factor VIIIa in a phospholipid-dependent reaction that could be blocked by an antifactor IX antibody. Factor IXa-catalyzed inactivation correlated with proteolytic cleavages within the A1 subunit of factor VIIIa and within the heavy chain (contiguous A1-A2-B domains) of factor VIII. Furthermore, a relatively slow conversion of factor VIII ...
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