Residual factor VII activity and different hemorrhagic phenotypes in CRM(+) factor VII deficiencies (Gly331Ser and Gly283Ser)
Autor: | Mirko, Pinotti, Daniela, Etro, Debora, Bindini, Maria Luisa, Papa, Giuseppina, Rodorigo, Angiola, Rocino, Guglielmo, Mariani, Nicola, Ciavarella, Francesco, Bernardi, Marko, Pinotti, Dániela, Etro, Guglieuto, Mariani |
---|---|
Rok vydání: | 2002 |
Předmět: |
Adult
Male Factor VII Deficiency Immunology Mutant Hemorrhage Biology Cross Reactions medicine.disease_cause Biochemistry law.invention chemistry.chemical_compound Structure-Activity Relationship law hemic and lymphatic diseases medicine Thromboplastin Humans cardiovascular diseases Aged Alanine Aged 80 and over Mutation Chymotrypsin Polymorphism Genetic Factor VII Base Sequence Homozygote Cell Biology Hematology Molecular biology Phenotype chemistry Amino Acid Substitution Glycine Recombinant DNA biology.protein Mutagenesis Site-Directed Female |
Zdroj: | Blood. 99(4) |
ISSN: | 0006-4971 |
Popis: | Two cross-reacting material–positive (CRM+) factor VII (FVII) mutations, associated with similar reductions in coagulant activity (2.5%) but with mild to asymptomatic (Gly331Ser, c184 [in chymotrypsin numbering]) or severe (Gly283Ser, c140) hemorrhagic phenotypes, were investigated. The affected glycines belong to structurally conserved regions in the c184 through c193 and c140s activation domain loops, respectively. The natural mutants 331Ser-FVII and 283Ser-FVII were expressed, and in addition 331Ala-FVII and 283Ala-FVII were expressed because 3 functional serine-proteases bear alanine at these positions. The 331Ser-FVII, present in several asymptomatic subjects, showed detectable factor Xa generation activity in patient plasma (0.7% ± 0.2%) and in reconstituted system with the recombinant molecules (2.7% ± 1.1%). The reduced activity of recombinant 283Ala-FVII (7.2% ± 2.2%) indicates that the full function of FVII requires glycine at this position, and the undetectable activity of 283Ser-FVII suggests that the oxydrile group of Ser283 participates in causing severe CRM+ deficiency. Furthermore, in a plasma system with limiting thromboplastin concentration, 283Ser-FVII inhibited wild-type FVIIa activity in a dose-dependent manner. |
Databáze: | OpenAIRE |
Externí odkaz: |