Center for Gene Regulation in Health and Disease (GRHD)

Michael Kalafatis

Biochemistry of blood coagulation and thrombosis; identification of binding sites for protein-protein interaction; regulation of blood clotting and thrombosis at the surface of platelets and endothelial cell.

Chemistry and biochemistry of cancer; phosphorylation and carcinogenesis; identification of specific proteins involved in the control of cell proliferation.

Phosphorylation of blood clotting proteins by platelet kinases and significance of phosphorylation; signal transduction; identification of the molecular defect in patients with blood coagulation disorders.

  • Hanan Mohammad
    PhD Student
  • Jasmine Manouchehri
    PhD Student
  • Mahesheema Na
    PhD Student
  • Katherine Turner
    PhD Student
  • Joseph Wiencek
    PhD Student

1. Kalafatis, M. Identification des domaines fonctionnels du Facteur Willebrand humain l'aide d'anticorps monoclonaux.  Thèse de Doctorat de l'Université Paris VI en Biochimie (Ph.D. University of Paris in Biochemistry) 1989. 

2. Girma, J.P., Kalafatis, M., Pietu, G., Lavergne, J.M., Chopek, M.W., Edgington, T.S., and Meyer, D.  Mapping of distinct von Willebrand Factor domains interacting with platelet GPIb and GPIIb/IIIa and with collagen using monoclonal antibodies.  Blood, 1986, 67, 1356-1366. 

3. Kalafatis, M., Takahashi, Y., Girma, J.P., and Meyer, D.  Localization of a collagen interactive domain of human von Willebrand Factor between amino acid residues Gly 911 and Glu 1365.  Blood, 1987, 70, 1577-1583. 

4. Takahashi, Y., Kalafatis, M., Girma, J.P., Sewerin, K., Andersson, L.O., and Meyer, D.  Localization of a Factor VIII binding domain on a 34 kDa fragment of the N-terminal portion of von Willebrand Factor.  Blood, 1987, 70, 1679-1682. 

5. Takahashi, Y., Kalafatis, M., Girma, J.P., and Meyer, D.  Abnormality of the N-terminal portion of von Willebrand Factor in type IIA and IIC von Willebrand disease.  Thromb. Haemost., 1988, 60, 498-505. 

6. Kalafatis, M., Jenny, R.J., Mann, and K.G.  Identification and characterization of a phospholipid-binding site of bovine factor Va.  J. Biol. Chem., 1990, 265, 21580-21589. 

7. Kalafatis, M., Rand, M.D., Jenny, R.J., Ehrlich, Y.H., and Mann, K.G. Phosphorylation of factor Va and VIIIa by activated platelets.  Blood, 1993, 81, 704-719. 

8. Xue, J., Kalafatis, M., and Mann, K.G.  Determination of the disulfide bridges in factor Va light chain.  Biochemistry, 1993, 32, 5917-5923. 

9. Kalafatis, M., and Mann, K.G.  Role of the membrane in the inactivation of factor Va by activated protein C.  J. Biol. Chem., 1993, 268, 27246-27257. 

10. Kalafatis, M., Rand, M.D., and Mann, K.G.  Factor Va-membrane interaction is mediated by two regions located on the light chain of the cofactor.  Biochemistry, 1994, 33, 486-493. 

11. Butenas, S., Lawson, J.H, Kalafatis M., and Mann, K.G.  Cooperative interaction of divalent metal ions, substrate, and tissue factor with factor VIIa.  Biochemistry, 1994 33, 3449-3456. 

12. Rand, M.D.,  Kalafatis, M., and Mann, K.G.  Platelet coagulation factor Va:  The major secretory platelet phosphoprotein.  Blood, 1994, 83, 2180-2190. 

13. Kalafatis, M., Xue, J., Lawler, C.M., and Mann, K.G.  Contribution of the heavy and light chains of factor Va to the interaction with factor Xa.  Biochemistry, 1994, 33, 6538-6545. 

14. Lu, D., Kalafatis, M., Mann, K. G., and Long, G. L.  Loss of membrane-dependent factor Va cleavage:  A mechanistic interpretation of the pathology of protein CVERMONT.  Blood, 1994, 84, 687-690. 

15. Lawson, J.H., Kalafatis, M., Stram, S., and Mann, K.G.  A model for the tissue factor pathway to thrombin.  1. An empirical study  J. Biol. Chem., 1994, 269, 23357-23366. 

16. Xue, J., Kalafatis, M., Silveira, J.R., Kung, C., and Mann, K.G.  Determination of the disulfide bridges location in bovine factor Va heavy chain.  Biochemistry, 1994 33, 13109-13116. 

17. Kalafatis, M., Rand, M.D., and Mann, K.G.  The mechanism of inactivation of human factor V and human factor Va by activated protein C.  J. Biol. Chem., 1994, 269, 31869-31880. 

18. Kalafatis, M., Bertina, R.M., Rand, M.D., and Mann, K.G.  Characterization of the molecular defect in factor VR506Q. J. Biol. Chem., 1995, 270, 4053-4057. 

19. Kalafatis, M., and Mann, K.G.  Factor V Leiden and Thrombophilia.  N. Engl. J. Med., 1995, 332, 1382-1383. 

20. Camire, R.M., Kalafatis, M., Cushman, M., Tracy, R.P., Mann, K.G., and Tracy, P.B.  The mechanism of inactivation of platelet-derived factor Va from normal and APC-resistant individuals by activated protein C.  J. Biol. Chem., 1995, 270, 20794-20800.   

21. Kalafatis, M., Lu, D., Bertina, R.M., Long, G.L., and Mann, K.G.  Biochemical prototype for familial thrombosis:  A study combining a functional protein C mutation and factor V Leiden.  Arterioscler. Thromb. Vasc. Biol., 1995, 15, 2181-2187.   

22. Kalafatis, M., Haley, P.E., Lu, D., Bertina, R.M., Long, G.L., and Mann, K.G.  Proteolytic events that regulate factor V activity in whole plasma from normal and activated protein C (APC)-resistant individuals during clotting:  An insight into the APC-resistance assay.  Blood, 1996, 87, 4695-4707.   

23. Lu, D., Kalafatis, M., Mann, K.G., and Long, G.L.  Comparison of activated protein C/protein S-mediated inactivation of human factor VIII and factor V.  Blood, 1996, 87, 4708-4717.   

24. Simioni, P., Kalafatis, M., Millar D.S., Henderson, S.C., Luni, S., Cooper, D.N., and  Girolami, A.  Compound heterozygous protein C deficiency resulting in the presence of only the ¿ form of protein C in plasma.  Blood, 1996, 88, 2101-2108.   

25. Bajzar, L., Kalafatis, M., Simioni, P., and Tracy, P.B.  An antifibrinolytic mechanism describing the prothrombotic effect of factor VLeiden.  J. Biol. Chem., 1996, 271, 22949-22952.   

26. Butenas, S., Kalafatis M., and Mann, K.G.  Analysis of tissue plasminogen activator specificity using peptidyl fluorogenic substrates.  Biochemistry, 1997, 36, 2123-2131. 

27. van ¿t Veer, C., Golden, N.J., Kalafatis, M., and Mann, K.G.  Inhibitory mechanism of the protein C pathway on tissue factor induced thrombin generation.  Synergistic effect in combination with tissue factor pathway inhibitor.  J. Biol. Chem., 1997, 272, 7983-7994. 

28. Mann, K.G., Hockin, M.F., Begin, K.J., and Kalafatis, M.  Activated protein C cleavage of factor Va leads to dissociation of the A2 domain.  J. Biol. Chem., 1997, 272, 20678-20683. 

29. van ¿t Veer, C., Kalafatis, M., Bertina, R.M., Simioni, P., and Mann, K.G.  Increased tissue factor-initiated prothrombin activation as a result of the Arg506¿Gln mutation in factor VLEIDEN.  J. Biol. Chem., 1997, 272, 20721-20729. 

30. Egan, J.O., Kalafatis, M., and Mann, K.G.  The effect of Arg306¿Ala and Arg506¿Gln substitutions in the inactivation of recombinant human factor Va by activated protein C and protein S.  Protein Science, 1997, 6, 2016-2027. 

31. van ¿t Veer, C., Golden, N.J., Kalafatis, M., Simioni, P., Bertina R.M., and Mann, K.G.  An in vitro analysis of the combination of factor VLeiden and hemophilia A.  Blood, 1997, 90, 3067-3072. 

32. Hockin, M.F., Kalafatis, M., Shatos, M.A., and Mann, K.G.  Protein C activation and factor Va inactivation on human umbilical vein endothelial cells.  Arterioscler. Thromb. Vasc. Biol., 1997, 17, 2765-2775. 

33. Kalafatis, M.  Identification and partial characterization of factor Va heavy chain-kinase from human platelets.  J. Biol. Chem., 1998, 273, 8459-8466. 

34. Camire, R.M., Kalafatis, M., Simioni, P., Girolami, A., and Tracy, P.B.  Platelet-derived factor Va/VaLeiden cofactor activities are sustained on the surface of activated platelets despite the presence of activated protein C.  Blood 1998, 91, 2818-2829. 

35. Long, G.L., Lu, D., Xie R., and Kalafatis, M.  Human protein S cleavage and inactivation by coagulation factor Xa.  J. Biol. Chem., 1998, 273, 11521-11526. 

36. Camire, R.M., Kalafatis, M., and Tracy, P.B.  Proteolysis of factor V by cathepsin G and elastase indicates that cleavage at Arg1545 optimizes cofactor function by facilitating factor Xa binding. Biochemistry, 1998, 37, 11896-11906. 

37. Castoldi, E., Kalafatis, M., Lunghi, B., Simioni, P., Ioannou, P.A., Petio, M., Girolami, A., Mann, K.G., and Bernardi, F.  Molecular bases of pseudo-homozygous APC resistance: The compound heterozygosity for FV R506Q and a FV null mutation results in the exclusive presence of FV Leiden molecules in plasma.  Thromb. Haemost. 1998, 80, 403-406. 

38. Simioni, P., Kalafatis, M., Manfrin, D., Tormene, D., and Girolami, A.  Factor V variants, activated protein C resistance and venous thromboembolism.  Blood Coagul.Fibrinolysis. 1998, 9, 661-2. 

39. Kalafatis, M., Bernardi, F., Simioni, P., Lunghi B., Girolami, A and Mann, K.G.  Phenotype and genotype expression in pseudohomozygous factor VLEIDEN.  The need for phenotype analysis. Arterioscler. Thromb. Vasc. Biol. 1999, 19, 336-342. 

40. Hockin, M.F., Cawthern, K.M., Kalafatis, M., and Mann, K.G.  A model describing the inactivation of factor Va by activated protein C (APC):  Bond cleavage, fragment dissociation and product inhibition.  Biochemistry 1999, 38, 6918-6934. 

41. Castoldi, E., Simioni, P., Kalafatis, M., Lunghi, B., Tormene, D., Girelli, D., Girolami, A., and Bernardi, F.  Combinations of four mutations (FV R506Q, FVH1299R, FVY1702C, PT20210G/A) affecting the prothrombinase complex in a thrombophilic family.  Blood 2000, 96, 1443-1448. 

42. Simioni, P., Vianello, F., Kalafatis, M., Barzon, L., Ladogana, S., Paolucci, P., Carotenuto, M., Dal Bello, F., Palù, P., and Girolami A.  A dysfunctional factor X (Factor X San Giovanni Rotondo) Present at Homozygous and Double heterozygous level: Identification of a novel micro-deletion (delC556) and missense mutation (Lys408¿Asn) in the factor X gene.  A Study of an Italian Family.  Thromb.Res. 2001 101, 219-230. 

43. Kalafatis, M. and Mann, K.G.  The role of the membrane in the inactivation of factor Va by plasmin.  Amino acid region 307-348 of factor V plays a critical role for factor Va cofactor function.  J. Biol. Chem. 2001, 276, 18614-18623. 

44. Kalafatis, M., Simioni, P., and Bernardi, F.  Phenotype and genotype expression in pseudohomozygous R2 factor V.  Blood 2001, 98, 1988-1989. 

45. Simioni, P., Kalafatis M., Tormene D., Luni, S., Zerbinati, P., Barzon, L., Palù, G., and Girolami A.  Abnormal propeptide processing resulting in the presence of two abnormal species of protein C in plasma.  Characterization of the dysfunctional protein C Padua3 (Protein CR-1L/propeptide).  Thromb. Haemost. 2001, 86, 1017-1022. 

46. Silveira, J.R., Kalafatis, M., and Tracy, P.B.  Carbohydrate moieties on factor V, but not the derived cofactor, factor Va, regulate its inactivation by activated protein C.  Biochemistry 2002, 41, 1672-1680. 

47. Hung, K., Sun, X., Ding, H., Kalafatis, M., Simioni P., and Guo B.  A MALDI-TOF based mini sequencing method for screening of the G1691¿A mutation in the factor V gene.  Blood Coagul. Fibrinolysis. 2002, 13, 117-122. 

48. Kalafatis, M., Simioni, P., Tormene, D., Beck, D.O., Luni, S., and Girolami, A.  Isolation and characterization of an anti-factor V antibody causing activated protein C resistance from a patient with severe thrombotic manifestations.  Blood  2002, 99, 3985-3992. 

49. Singh, L.S. and Kalafatis, M.  Sequencing of full length cDNA encoding the ¿ and ¿ subunits of human casein kinase II from human platelets and megakaryocytic cells.  Expression of casein kinase II¿ intronless gene in a megakaryocytic cell line.  Biochemistry 2002, 41, 8935-8940. 

50. Kalafatis, M. and Beck, D.O.  Identification of a binding site for blood coagulation factor Xa on the heavy chain of factor Va.  Amino acid residues 323-331 of factor V contain an interactive site for activated factor X.  Biochemistry.  2002, 41, 12715-12728. 

51. Singh, L.S., Bukys, M.A., Beck, D.O., and Kalafatis, M.  Amino acids Glu323, Tyr324, Glu330, and Val331 of factor Va heavy chain are essential for expression of cofactor activity.  J. Biol. Chem. 2003, 278, 28335-28345. 

52. Kalafatis, M., Beck, D.O., and Mann, K.G.  Structural requirements for expression of factor Va activity.  J. Biol. Chem. 2003, 278, 33550-33561. 

53. Beck, D.O., Bukys, M.A., Singh, L.S., Szabo, K.A. and Kalafatis, M.  The contribution of amino acid region Asp695-Tyr698 of factor V to procofactor activation and factor Va function.  J. Biol. Chem. 2004, 279, 3084-3095. 

54. Gould, W.R., Simioni, P., Silveira, J.R., Luni S., Kalafatis M., and Tracy P.B. Megakaryocytes endocytose and subsequently modify human plasma-derived factor V in vivo to form the platelet-derived pool.  J. Thromb. Haemost. 2005, 3, 450-456. 

55. Bukys, M.A., Blum, M.A., Young, P.Y, Bruffato, N., Nesheim, M.E., and Kalafatis, M.  Incorporation of Factor Va into Prothrombinase is required for coordinated cleavage of Prothrombin by Factor Xa.  J. Biol. Chem. 2005, 280, 27393-27401. 

56. Orban, T., Kalafatis, M., and Gogonea, V.  Completed Three-Dimensional Model of Human Coagulation Factor Va.  Molecular Dynamics Simulations and Structural Analyses.  Biochemistry 2005, 44, 13082-13090. 

57. Bukys, M.A., Orban, T., Kim, P.Y., Beck, D.O., Nesheim, M.E., and Kalafatis, M.  The structural integrity of anion binding exosite I of thrombin is required and sufficient for timely activation of factor V and factor VIII.  J. Biol. Chem. 2006, 281, 18569-18580. 

58. Butenas, S., Orfeo, T., Kalafatis, M., and Mann K.G.  Peptidomimetic inhibitors for activated protein C: Implications for hemophilia management.  J. Thromb. Haemost. 2006, 4, 2411-2416. 

59. Bukys, M.A., Kim, P.Y., Nesheim, M. E., and Kalafatis, M.  A control switch for prothrombinase.  A hirudin-like peptide from the COOH-terminus of factor Va heavy chain regulates the rate and pathway for the activation of prothrombin by prothrombinase.  J. Biol. Chem. 2006, 281, 39194-39204. 

60. Erdogan, E., Bukys, M.A., Orfeo T., Mann, K.G., and Kalafatis, M.  Identification of an inactivating cleavage site for thrombin on the heavy chain of factor Va.  Thromb. Haemost. 2007, 98, 998-1006. 

61. Erdogan, E., Bukys, M.A., and Kalafatis, M.  The contribution of amino acids 1508-1515 of factor V to light chain formation.  J. Thromb. Haemost. 2008, 6, 118-124 

62. Bukys, M.A. Orban, T., Kim. P.Y., Nesheim, M. E., and Kalafatis, M.  The interaction of fragment 1of prothrombin with the membrane surface is a prerequisite for optimum expression of factor Va cofactor activity within prothrombinase.  Thromb. Haemost., 2008, 99, 511-522. 

63. Barhoover, M.A., Orban, T., Beck, D.O., Bukys, M.A., and Kalafatis, M.  The contribution of amino acid region 334-335 from factor Va heavy chain to the catalytic efficiency of prothrombinase.  Biochemistry, 2008, 47, 6840-6850. 

64. Hirbawi, J., Bukys, M.A., Barhoover, M.A., Erdogan, E., and Kalafatis M.  Role of the acidic hirudin-like COOH-terminal amino acid region of factor Va heavy chain in the enhanced function of prothrombinase.  Biochemistry, 2008, 47, 7963-7974. 

65. Barhoover, M.A., Orban, T. Bukys, M.A., and Kalafatis M.  Cooperative regulation of the activity of factor Xa within prothrombinase by discrete amino acid regions from factor Va heavy chain.  Biochemistry, 2008, 47, 12835-12843. 


66 Kalafatis, M., Girma, J.P., and Meyer, D.  Identification des domaines fonctionnels du facteur Willebrand humain.  Innov. Tech. Biol. Med. (ITBM), 1988, 9, 682-690. 

67. Kalafatis, M., Swords, N.A., Rand, M.D., and Mann, K.G.  Membrane-dependent reactions in blood coagulation.  Role of the vitamin K-dependent enzyme complexes.  Molecular Basis of Disease.  Biochim. Biophys. Acta, 1994, 1227, 113-129. 

68. Mann, K.G, and Kalafatis, M.  The coagulation explosion.  Cerebrovascular Diseases, 1995, 5, 93-97. 

69. Kalafatis, M., Egan, J.O., van¿t Veer, C., and Mann, K.G.  Regulation and regulatory role of ¿-carboxyglutamic acid containing clotting factors.  Critical Reviews in Eukaryotic Gene Expression, 1996, 6, 87-101.   

70. Kalafatis, M.  The molecular basis for activated protein C-resistance.  American Heart Association Newsletter, (Thrombosis Council) Fall 1996, pp. 7-9. 

71. Kalafatis, M., and Mann, K.G.  Factor VLeiden and Thrombophilia.  Arterioscler. Thromb. Vasc. Biol., 1997, 17, 620-627. 

72. Kalafatis, M., Egan, J.O., van¿t Veer, C., Cawthern, K.M., and Mann, K.G.  The Regulation of clotting factors.  Critical Reviews in Eukaryotic Gene Expression, 1997, 7, 241-280. 

73. Mann, K.G. and Kalafatis, M.  Factor V:  A Combination of Dr. Jeckyll and Mr. Hyde.  Blood, 2003, 101, 20-30. (Figure 2 of the manuscript is the cover picture of volume 101, number 1, of January 1 2003 edition of Blood). 

74. Kalafatis, M.  Factor V: A plethora of potent anticoagulant molecules.  Current Opinion in Hematology, 2005, 12, 141-148. 


75. Girma, J.P., Kalafatis, M., and Meyer, D.  Mapping of von Willebrand Factor functional domains with monoclonal antibodies.  In: Factor VIII/von Willebrand factor.  Biological and clinical advances. Eds. N.L. Ciavarella, Z.R. Ruggeri, T.S. Zimmerman; 1986 pp. 137-148. Wichtig Editore, Italy. 

76. Girma, J.P., Kalafatis, M., Takahashi, Y., and Meyer, D.  Recognition of three distinct functional domains of human von Willebrand factor using monoclonal antibodies.  In: Utilisation of monoclonal antibodies for the understanding and detection of platelet activity.  Ed. J. McGregor; 1986, pp. 219-225.  Elsevier Science publishers B.V., The Netherlands. 

77. Kalafatis, M., Krishnaswamy, S., Rand, M.D., and Mann, K.G.  Factor V.  In: Proteolytic Enzymes in Coagulation, Fibrinolysis, and Complement Activation.  Methods Enzymology, 1993, 222, 224-236. 

78. Kalafatis, M., Egan, J.O., and Mann, K.G.  Coagulation Factors.  In:  Endothelium in Clinical Practice., Eds. Rubanyi/Dzau 1996 pp 245-264.  Marcel Dekker, Inc., publisher, New York, NY USA. 

79. Kalafatis, M., van ¿t Veer, C., and Mann, K.G.  Coagulation Factors.  In: Encyclopedic Reference of Vascular Biology and Pathology.  Ed. A. Bikfalvi; 2000, pp 49-64.  Springer-Verlag Berlin Heidelberg, Germany. 

80. Kalafatis, M., and Mann K.G.  Factor V:  Dr Jeckyl and Mr Hyde.  In: Proceedings of the hemophilia care in the new millennium.  Eds. D.M. Monroe, U. Hedner, M.R. Hoffman, C. Negrier, G.F. Savidge, and G.C. White; 2001, pp 31-43.  Kluwer Academic/Plenum Publishers, New York, NY, USA. 

81. Kalafatis, M., Negrescu, E., Byzova, T., and Plow, E.F.  Platelets and prothrombin.  In:  Platelet Function: Assessment, Diagnosis, and Function.  Eds. M. Quinn and D. Fitzgerald; 2005, pp 279-296.  Humana Press Inc., Totowa, NJ, USA.