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PtFVa (Pseudonaja Textilis Venom-Derived Factor Va) Retains Structural Integrity Following Proteolysis by Activated Protein C.

ABSTRACT: OBJECTIVE: The Australian snake venom ptFV (Pseudonaja textilis venom-derived factor V) variant retains cofactor function

SUBMITTER: Schreuder M

PROVIDER: S-EPMC8288481 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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ptFVa (Pseudonaja Textilis Venom-Derived Factor Va) Retains Structural Integrity Following Proteolysis by Activated Protein C.

Schreuder Mark M Liu Xiaosong X Cheung Ka Lei KL Reitsma Pieter H PH Nicolaes Gerry A F GAF Bos Mettine H A MHA

Arteriosclerosis, thrombosis, and vascular biology 20210624 8

OBJECTIVE: The Australian snake venom ptFV (Pseudonaja textilis venom-derived factor V) variant retains cofactor function despite APC (activated protein C)-dependent proteolysis. Here, we aimed to unravel the mechanistic principles by determining the role of the absent Arg306 cleavage site that is required for the inactivation of FVa (mammalian factor Va). APPROACH AND RESULTS: Our findings show that in contrast to human FVa, APC-catalyzed proteolysis of ptFVa at Arg306 and Lys507 does not abro ...[more]

PMID: 34162230

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