title: Expression and characterization of six clinically relevant uroporphyrinogen decarboxylase gene mutations.
abstract: The functional consequence of six uroporphyrinogen decarboxylase (UROD) gene mutations found in Danish patients with familial porphyria cutanea tarda was investigated. Wild-type UROD and the 6 mutants (3 missense, 1 nonsense and 2 frameshift mutants) were cloned and expressed using the prokaryotic gGEX-6P system, in which the protein is produced in fusion with glutathione S-transferase (GST). Enzymatic activity of the purified recombinant mutant fusion proteins ranged from undetectable to less than 12% of the recombinant wild-type protein. Mutant proteins cleaved from the GST part did not retain any catalytic activity. These observations can be ascribed to the structure/function relationships of the enzyme, and the fact that the enzyme is a dimer in its active form. Although the clinical manifestation of familial porphyria cutanea tarda is complex, the findings support the notion that different mutations may affect individuals differently.
authors.affiliation: Department of Clinical Biochemistry and Clinical Genetics, Odense University Hospital, Odense, Denmark. lchristiansen@health.sdu.dk
authors.forename: L
authors.initials: L
authors.lastname: Christiansen
authors.forename: J
authors.initials: J
authors.lastname: Brøns-Poulsen
authors.forename: M
authors.initials: M
authors.lastname: Hørder
authors.forename: A
authors.initials: A
authors.lastname: Brock
authors.forename: N E
authors.initials: NE
authors.lastname: Petersen
mesh_terms: D015870:Gene Expression; D006801:Humans; D007700:Kinetics; D009154:Mutation / Q000235:genetics*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D014575:Uroporphyrinogen Decarboxylase / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D014575:Uroporphyrinogen Decarboxylase