title: A proteomic approach for the characterization of C677T mutation of the human gene methylenetetrahydrofolate reductase.
abstract: Methylenetetrahydrofolate reductase (MTHFR) catalyzes the conversion of methylenetetrahydrofolate (CH2H4folate) to methyltetrahydrofolate (CH3H4folate). The C677T mutation is a common polymorphism of the human enzyme that leads to the replacement of Ala222Val, thermolability of MTHFR, and mild elevation of plasma homocysteine levels. A mild hyperhomocysteinemia is known to be risk factor for cardiovascular and thrombotic diseases, ischemic stroke, neural tube defects, late on-set dementia, and pregnancy complications. Human plasma of subjects carrying the C677T mutation in the MTHFR gene has been investigated for their protein pattern in order to identify novel molecular hallmarks. 2-D analysis of the plasma protein allowed the identification of a specific pattern associated with the TT mutant genotype. Noteworthy, we found one spot shifted to a more basic pI in mutant individuals, and MS identification corresponded to vitamin D-binding protein (DBP or group component (Gc) globulin). MS/MS peptide sequencing allowed to discriminate different allelic variants in the investigated clinical groups. These data confirmed by molecular genetic analysis highlight the novel association between the C677T MTHFR genotype with the Gc2 polymorphism of the DBP. Moreover, we found a quantitative reduction of Apolipoprotein A-I in mutant individuals, which was associated, in previous studies by others to an increased cardiovascular risk.
authors.affiliation: Department of Biological and Environmental Sciences and Technologies, University of Lecce, Lecce, Italy.
authors.forename: Marilena
authors.initials: M
authors.lastname: Greco
authors.forename: Fernanda
authors.initials: F
authors.lastname: Chiriacò
authors.forename: Piero
authors.initials: P
authors.lastname: Del Boccio
authors.forename: Luigi
authors.initials: L
authors.lastname: Tagliaferro
authors.forename: Raffaele
authors.initials: R
authors.lastname: Acierno
authors.forename: Paola
authors.initials: P
authors.lastname: Menegazzi
authors.forename: Eleonora
authors.initials: E
authors.lastname: Pinca
authors.forename: Francesco
authors.initials: F
authors.lastname: Pignatelli
authors.forename: Carlo
authors.initials: C
authors.lastname: Storelli
authors.forename: Giorgio
authors.initials: G
authors.lastname: Federici
authors.forename: Andrea
authors.initials: A
authors.lastname: Urbani
authors.forename: Michele
authors.initials: M
authors.lastname: Maffia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics; D002318:Cardiovascular Diseases / Q000235:genetics / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation; D011110:Polymorphism, Genetic; D040901:Proteomics
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2)