title: Interspecies nuclear transfer embryos reconstructed from cat somatic cells and bovine ooplasm.
abstract: This study was conducted to investigate the developmental capacity of domestic cat-bovine reconstructed embryos via interspecies somatic cell nuclear transfer (iSCNT) and to observe the mitochondrial DNA (mtDNA) content of the iSCNT embryos. The iSCNT embryos were generated using mixed-breed domestic cat fibroblasts as donor cells and enucleated bovine oocytes as the recipient cytoplasm. When the developmental capacities of iSCNT embryos and parthenogenic bovine embryos were compared, there was no difference (P>0.05) in the rates of cleavage and development to the 8-cell stage (86.6 vs. 84.0% and 32.2 vs. 36.2%, respectively). However, in contrast to development of parthenogenic embryos to the morula and blastocyst stages, no iSCNT embryos (0/202) developed beyond the 8-cell stage. For mtDNA analysis, iSCNT embryos at the 1-cell, 2-cell, 4-cell and 8-cell stages were randomly selected. Both cat and bovine mtDNA quantification analysis were performed using quantitative PCR. The levels of both cat and bovine mtDNA in cat-bovine iSCNT embryos varied at each stage of development. The cat mtDNA concentration in the iSCNT embryos was stable from the 1-cell to 8-cell stages. The bovine mtDNA in the iSCNT embryos at the 8-cell stage was significantly lower than that at the 4-cell stage (P<0.05). No difference in the proportions of cat mtDNA in the iSCNT embryos was found in any of the observed developmental stages (1- through 8-cell stages). In conclusion, bovine cytoplasm supports domestic cat nucleus development through the 8-cell stage. The mtDNA genotype of domestic cat-bovine iSCNT embryos illustrates persistence of heteroplasmy, and the reduction in mtDNA content might reflect a developmental block at the 8-cell stage.
authors.affiliation: Department of Obstetrics, Gynecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Ampika
authors.initials: A
authors.lastname: Thongphakdee
authors.forename: Shuji
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Kei
authors.initials: K
authors.lastname: Imai
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Inaba
authors.forename: Mariko
authors.initials: M
authors.lastname: Tasai
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tagami
authors.forename: Keijiro
authors.initials: K
authors.lastname: Nirasawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagai
authors.forename: Norio
authors.initials: N
authors.lastname: Saito
authors.forename: Mongkol
authors.initials: M
authors.lastname: Techakumphu
authors.forename: Kumiko
authors.initials: K
authors.lastname: Takeda
mesh_terms: D000818:Animals; D002415:Cats; D002417:Cattle; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000378:metabolism; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D005786:Gene Expression Regulation; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000378:metabolism*; D010057:Oviducts / Q000378:metabolism; D013045:Species Specificity
chemical_list: D004272:DNA, Mitochondrial