title: Transmitochondrial mice as models for primary prevention of diseases caused by mutation in the tRNA(Lys) gene.
abstract: We generated transmitochondrial mice (mito-mice) that carry a mutation in the tRNA(Lys) gene encoded by mtDNA for use in studies of its pathogenesis and transmission profiles. Because patients with mitochondrial diseases frequently carry mutations in the mitochondrial tRNA(Lys) and tRNA(Leu(UUR)) genes, we focused our efforts on identifying somatic mutations of these genes in mouse lung carcinoma P29 cells. Of the 43 clones of PCR products including the tRNA(Lys) or tRNA(Leu(UUR)) genes in mtDNA of P29 cells, one had a potentially pathogenic mutation (G7731A) in the tRNA(Lys) gene. P29 subclones with predominant amounts of G7731A mtDNA expressed respiration defects, thus suggesting the pathogenicity of this mutation. We then transferred G7731A mtDNA into mouse ES cells and obtained F0 chimeric mice. Mating these F0 mice with C57BL/6J (B6) male mice resulted in the generation of F1 mice with G7731A mtDNA, named "mito-mice-tRNA(Lys7731)." Maternal inheritance and random segregation of G7731A mtDNA occurred in subsequent generations. Mito-mice-tRNA(Lys7731) with high proportions of G7731A mtDNA exclusively expressed respiration defects and disease-related phenotypes and therefore are potential models for mitochondrial diseases due to mutations in the mitochondrial tRNA(Lys) gene. Moreover, the proportion of mutated mtDNA varied markedly among the pups born to each dam, suggesting that selecting oocytes with high proportions of normal mtDNA from affected mothers with tRNA(Lys)-based mitochondrial diseases may be effective as a primary prevention for obtaining unaffected children.
authors: Faculty of Life and Environmental Sciences and International Institute for Integrative Sleep Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
authors: Akinori
authors: A
authors: Shimizu
authors: Takayuki
authors: T
authors: Mito
authors: Chisato
authors: C
authors: Hayashi
authors: Emi
authors: E
authors: Ogasawara
authors: Ryusuke
authors: R
authors: Koba
authors: Issei
authors: I
authors: Negishi
authors: Keizo
authors: K
authors: Takenaga
authors: Kazuto
authors: K
authors: Nakada
authors: Jun-Ichi
authors: J
authors: Hayashi
mesh_terms: D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D004272:DNA, Mitochondrial / Q000235:genetics*; D004195:Disease Models, Animal; D053595:Embryonic Stem Cells / Q000166:cytology; D030342:Genetic Diseases, Inborn / Q000517:prevention & control*; D005838:Genotype; D051379:Mice; D008817:Mice, Mutant Strains; D028361:Mitochondrial Diseases / Q000235:genetics* / Q000517:prevention & control; D008969:Molecular Sequence Data; D009865:Oocytes / Q000166:cytology*; D010101:Oxygen Consumption / Q000502:physiology; D017354:Point Mutation / Q000235:genetics; D012357:RNA, Transfer, Lys / Q000235:genetics*; D017382:Reactive Oxygen Species / Q000378:metabolism; D017422:Sequence Analysis, DNA; D018183:Transplantation Chimera / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial; D012357:RNA, Transfer, Lys; D017382:Reactive Oxygen Species
keywords: mtDNA heteroplasmic mutation; mutated mtDNA segregation; preimplantation genetic diagnosis; selection of oocytes