title: Expression of wild-type and mutant human ornithine transcarbamylase genes in Chinese hamster ovary cells and lack of dominant negative effect of R141Q and R40H mutants.
abstract: Chinese hamster ovary cultured cells were transformed to continuously express wild-type and two mutant ornithine transcarbamylase genes, R141Q and R40H. In addition, these cells were transfected to transiently express the same genes. The R141Q mutation abolishes the enzymatic activity, and the amount of "mature" protein present in transfected cells is equivalent to the wild type. The R40H mutation causes a reduction of enzymatic activity to approximately 26 to 35% of wild type concomitant with a significant reduction in the amount of protein present. Transfection with wild-type and mutant genes together in various proportions did not reveal dominant negative effects of the two mutations studied. This expression system can be used to examine the deleterious effect of private mutations or lack thereof in families with ornithine transcarbamylase deficiency as well as evaluate the potential dominant negative effects of gene delivery for treatment of ornithine transcarbamylase deficiency.
authors: Department of Medicine, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors: L
authors: L
authors: Augustin
authors: M
authors: M
authors: Mavinakere
authors: H
authors: H
authors: Morizono
authors: M
authors: M
authors: Tuchman
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D018076:DNA, Complementary / Q000235:genetics; D004790:Enzyme Induction / Q000235:genetics; D005799:Genes, Dominant; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D009954:Ornithine Carbamoyltransferase / Q000096:biosynthesis* / Q000235:genetics; D020163:Ornithine Carbamoyltransferase Deficiency Disease; D017354:Point Mutation; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D011993:Recombinant Fusion Proteins; D008156:Luciferases; D009954:Ornithine Carbamoyltransferase