A recurrent Gly43Asp substitution in coagulation Factor X rigidifies its catalytic pocket and impairs catalytic activity and intracellular trafficking

Marzia Menegatti*, Anna Vangone, Roberta Palla, Giuseppe Milano, Luigi Cavallo, Romina Oliva, Raimondo De Cristofaro, Flora Peyvandi

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

Factor X (FX) deficiency is one of the most severe among recessively inherited coagulation disorders. The homozygous Gly222Asp mutation (Gly43Asp in the chymotrypsinogen numbering) on the FX gene was found in fifteen patients with severe FX deficiency (FX:C < 1%). The Gly43 residue is located at the highly conserved 42-58 residues region shared among all trypsinogen-like proteins. In vitro expression studies showed that the replacement of a neutral Gly by a charged Asp residue into the so-called loop-40 of the FX (comprising residues from 42 to 58) causes an impairment of its catalytic competence as well as a secretion defect. Steady state kinetic studies showed also a severe defect of activation by FVIIa of the FX43Asp. Surprisingly, molecular dynamics studies clearly indicated that the Gly43Asp mutation neither disrupts nor destabilizes the FXa native structure of the catalytic site. Rather, it makes it more rigid, by thickening the H-bonding network around its catalytic site. Altogether, the defects of FX43Asp explain the severe bleeding symptoms in the patients and outline the relevance of the plasticity in the FXa catalytic pocket for maintenance of its catalytic competence.

Original languageEnglish (US)
Pages (from-to)481-487
Number of pages7
JournalThrombosis Research
Volume133
Issue number3
DOIs
StatePublished - Mar 1 2014

Keywords

  • Amidolytic activity
  • Catalytic activity
  • Factor X Gly43Asp mutation
  • Factor X deficiency
  • Molecular dynamics

ASJC Scopus subject areas

  • Hematology

Fingerprint Dive into the research topics of 'A recurrent Gly43Asp substitution in coagulation Factor X rigidifies its catalytic pocket and impairs catalytic activity and intracellular trafficking'. Together they form a unique fingerprint.

Cite this