Importance of individual residues in hydrophobic patch PLVIVGL (1481-1487) in FV-Short for synergistic TFPIα cofactor activity with protein S, an alanine-scanning study: AlphaFold-mediated prediction of FV-Short/TFPIα/protein S trimolecular complex structure.
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引用次数: 0
Abstract
Background: In the splice variant factor (F)V-Short, 702 residues are deleted from the B domain, resulting in exposure of an acid region (AR2; 1493-1537) that binds TFPIα. FV-Short and protein S serve as synergistic TFPIα cofactors in inhibition of FXa. In the preAR2 region, a hydrophobic patch PLVIVGL (1481-1487) is crucial for synergistic TFPIα-cofactor activity and assembly of FV-Short, TFPIα, and protein S.
Objectives: To elucidate the importance of individual residues in the PLVIVGL patch for synergism between FV-Short and protein S as TFPIα cofactors.
Methods: An alanine scanning of the hydrophobic patch was performed in which 7 FV-Short variants were created. The synergistic TFPIα-cofactor activity was analyzed by FXa inhibition and a microtiter-based assay tested binding between the proteins. AlphaFold 3 was used to predict protein-protein interactions between FV-Short, protein S, and TFPIα.
Results: Five of the 7 variants (V1483A, I1484A, V1485A, G1486A, and L1487A) demonstrated decreased synergistic TFPIα cofactor activity; in particular, G1486A and L1487A were severely affected. Neither wild-type FV-Short nor any of the mutants bound protein S in the absence of TFPIα. In the presence of TFPIα, wild-type FV-Short, P1481A, L1482A, and V1485A bound protein S, whereas V1483A, I1484A, G1486A, and L1487A did not. AlphaFold predicted an interaction between the hydrophobic patch in FV-Short and a hydrophobic patch in protein S involving residues 268-276 and 422-426.
Conclusion: Individual residues (V1483, I1484, G1486, and L1487) in the hydrophobic patch are demonstrated to be important for the synergistic TFPIα-cofactor activity and for the assembly of a trimolecular FXa-inhibitory complex.
期刊介绍:
The Journal of Thrombosis and Haemostasis (JTH) serves as the official journal of the International Society on Thrombosis and Haemostasis. It is dedicated to advancing science related to thrombosis, bleeding disorders, and vascular biology through the dissemination and exchange of information and ideas within the global research community.
Types of Publications:
The journal publishes a variety of content, including:
Original research reports
State-of-the-art reviews
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Scope of Contributions:
Editors invite contributions from both fundamental and clinical domains. These include:
Basic manuscripts on blood coagulation and fibrinolysis
Studies on proteins and reactions related to thrombosis and haemostasis
Research on blood platelets and their interactions with other biological systems, such as the vessel wall, blood cells, and invading organisms
Clinical manuscripts covering various topics including venous thrombosis, arterial disease, hemophilia, bleeding disorders, and platelet diseases
Clinical manuscripts may encompass etiology, diagnostics, prognosis, prevention, and treatment strategies.