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Kazuo Moriwaki - One of the best experts on this subject based on the ideXlab platform.
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Detection of recombinant haplotypes in wild mice (Mus Musculus) provides new insights into the origin of Japanese mice
2013Co-Authors: Mitsuo Nunome, Hiromichi Yonekawa, Kazuo Moriwaki, Kimiyuki Tsuchiya, Chikako Ishimori, Ken P. Aplin, Hitoshi SuzukiAbstract:Japanese house mice (Mus Musculus Molossinus) are thought to be a hybrid lineage derived from two prehistoric immigrants, the subspecies M. m. Musculus of northern Eurasia and M. m. castaneus of South Asia. Mice of the western European subspecies M. m. domesticus have been detected in Japanese ports and airports only. We examined haplotype structuring of a 200 kb stretch on chromosome 8 for 59 mice from throughout Eurasia, determining short segments ( 370–600 bp) of eight nuclear genes (Fanca, Spire2, Tcf25, Mc1r, Tubb3, Def8, Afg3l1 and Dbndd1) which are intermittently arranged in this order. Where possible we identified the subspecies origin for individual gene alleles and then designated haplotypes for concatenated alleles. We recovered 11 haplotypes among 19 Japanese mice examined, identified either as ‘intact ’ haplotypes derived from the subspecies Musculus (57.9%), domesticus (7.9%), and castaneus (2.6%), or as ‘recombinant’ haplotypes (31.6%). We also detected recombinant haplotypes unique to Sakhalin. The complex nature of the recombinant haplotypes suggests ancient introduction of all three subspecies components into the peripheral part of Eurasia or complicated genomi
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Detection of recombinant haplotypes in wild mice (Mus Musculus) provides new insights into the origin of Japanese mice.
Molecular ecology, 2010Co-Authors: Mitsuo Nunome, Hiromichi Yonekawa, Kazuo Moriwaki, Kimiyuki Tsuchiya, Chikako Ishimori, Ken Aplin, Hitoshi SuzukiAbstract:Japanese house mice (Mus Musculus Molossinus) are thought to be a hybrid lineage derived from two prehistoric immigrants, the subspecies M. m. Musculus of northern Eurasia and M. m. castaneus of South Asia. Mice of the western European subspecies M. m. domesticus have been detected in Japanese ports and airports only. We examined haplotype structuring of a 200 kb stretch on chromosome 8 for 59 mice from throughout Eurasia, determining short segments (approximately 370-600 bp) of eight nuclear genes (Fanca, Spire2, Tcf25, Mc1r, Tubb3, Def8, Afg3l1 and Dbndd1) which are intermittently arranged in this order. Where possible we identified the subspecies origin for individual gene alleles and then designated haplotypes for concatenated alleles. We recovered 11 haplotypes among 19 Japanese mice examined, identified either as 'intact' haplotypes derived from the subspecies Musculus (57.9%), domesticus (7.9%), and castaneus (2.6%), or as 'recombinant' haplotypes (31.6%). We also detected recombinant haplotypes unique to Sakhalin. The complex nature of the recombinant haplotypes suggests ancient introduction of all three subspecies components into the peripheral part of Eurasia or complicated genomic admixture before the movement from source areas. 'Intact'domesticus and castaneus haplotypes in other Japanese wild mice imply ongoing stowaway introductions. The method has general utility for assessing the history of genetic admixture and for disclosing ongoing genetic contamination.
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Establishment of germline-competent embryonic stem cell lines from the MSM/Ms strain
Mammalian Genome, 2009Co-Authors: Kimi Araki, Kazuo Moriwaki, Atsushi Yoshiki, Yuichi Obata, Toshihiko Shiroishi, Naoki Takeda, Naomi Nakagata, Ken-ichi YamamuraAbstract:MSM/Ms is an inbred mouse strain established from the Japanese wild mouse, Mus Musculus Molossinus , which has been phylogenetically distinct from common laboratory mouse strains for about 1 million years. The nucleotide substitution rate between MSM/Ms and C57BL/6 is estimated to be 0.96%. MSM/Ms mice display unique characteristics not observed in the commonly used laboratory strains, including an extremely low incidence of tumor development, high locomotor activity, and resistance to high-fat-diet-induced diabetes. Thus, functional genomic analyses using MSM/Ms should provide a powerful tool for the identification of novel phenotypes and gene functions. We report here the derivation of germline-competent embryonic stem (ES) cell lines from MSM/Ms blastocysts, allowing genetic manipulation of the M. m. Molossinus genome. Fifteen blastocysts were cultured in ES cell medium and three ES lines, Mol/MSM-1, -2, and -3, were established. They were tested for germline competency by aggregation with ICR morulae and germline chimeras were obtained from all three lines. We also injected Mol/MSM-1 ES cells into blastocysts of ICR or C57BL/6 × BDF1 mice and found that blastocyst injection resulted in a higher production rate of chimeric mice than did aggregation. Furthermore, Mol/MSM-1 subclones electroporated with a gene trap vector were also highly efficient at producing germline chimeras using C57BL/6 × BDF1 blastocyst injection. This Mol/MSM-1 ES line should provide an excellent new tool allowing the genetic manipulation of the MSM/Ms genome.
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Mouse inter-subspecific consomic strains for genetic dissection of quantitative complex traits
Genome research, 2008Co-Authors: Toyoyuki Takada, Hiromichi Yonekawa, Kazuo Moriwaki, Akihiko Mita, Akiteru Maeno, Takahiro Sakai, Hiroshi Shitara, Yoshiaki Kikkawa, Toshihiko ShiroishiAbstract:Consomic strains, also known as chromosome substitution strains, are powerful tools for assigning polygenes that control quantitative complex traits to specific chromosomes. Here, we report generation of a full set of mouse consomic strains, in which each chromosome of the common laboratory strain C57BL/6J (B6) is replaced by its counterpart from the inbred strain MSM/Ms, which is derived from Japanese wild mouse, Mus Musculus Molossinus. The genome sequence of MSM/Ms is divergent from that of B6, whose genome is predominantly derived from Western European wild mouse, Mus Musculus domesticus. MSM/Ms exhibits a number of quantitative complex traits markedly different from those of B6. We systematically determined phenotypes of these inter-subspecific consomic strains, focusing on complex traits related to reproduction, growth, and energy metabolism. We successfully detected more than 200 statistically significant QTLs affecting 26 traits. Furthermore, phenotyping of the consomic strains revealed that the measured values for quantitative complex traits often far exceed the range between B6 host and MSM/Ms donor strains; this may result from segregation of alleles or nonadditive interactions among multiple genes derived from the two mouse subspecies (that is, epistasis). Taken together, the results suggest that the inter-subspecific consomic strains will be very useful for identification of latent genetic components underlying quantitative complex traits.
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phylogeographic origin of hokkaido house mice Mus Musculus as indicated by genetic markers with maternal paternal and biparental inheritance
Heredity, 2006Co-Authors: Mie Terashima, Hiromichi Yonekawa, Kazuo Moriwaki, Kimiyuki Tsuchiya, Naoto Hanzawa, Shunsuke Furusawa, Agutinus Suyanto, Hitoshi SuzukiAbstract:We examined intraspecies genetic variation in house mice (Mus Musculus Molossinus) from the northern third of the Japanese Islands, in order to obtain evidence of the history of mouse colonization that might have shaped the current genetic diversity. We extended the previous sampling of mitochondrial cytochrome b sequence and added information from the Y-linked Sry gene and ribosomal RNA gene surveys. We distinguish mitochondrial haplotypes characteristic of the North Asian Musculus subspecies group (involving M. m. Musculus and M. m. Molossinus) as 'Mus', and that of the Southeast Asian castaneus subspecies group as 'CAS' (although the mice resemble Mus morphologically). There was a clear geographic partition of Mus and CAS types into southern and northern Hokkaido, respectively. Conversely, on Tohoku, the Mus and CAS types were interspersed without clear geographic subdivision. In contrast to the mtDNA data, all Hokkaido and Tohoku mice examined were found to possess a unique type for the Y-linked Sry gene, specific to Korea and Japan. Restriction site analysis of nuclear rDNA probe showed a consistent distribution of Mus and CAS types, as major and minor components, respectively, in the Hokkaido and Tohoku mice. These data support the previous notion that the Hokkaido and Tohoku mice experienced genetic hybridization between primary residents of CAS origin and Mus newcomers arriving via a southern route. The invasion of the Mus type could correspond with the evidence for arrival of prehistoric peoples. There are, however, alternative interpretations, including genetic admixture between Mus arriving by a southern route and CAS from a northern route.
Yuichi Wakabayashi - One of the best experts on this subject based on the ideXlab platform.
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The Japanese Wild-Derived Inbred Mouse Strain, MSM/Ms in Cancer Research
Cancers, 2021Co-Authors: Kazuhiro Okumura, Megumi Saito, Eriko Isogai, Yuichi WakabayashiAbstract:MSM/Ms is a unique inbred mouse strain derived from the Japanese wild mouse, Mus Musculus Molossinus, which has been approximately 1 million years genetically distant from standard inbred mouse strains mainly derived from M. m. domesticus. Due to its genetic divergence, MSM/Ms has been broadly used in linkage studies. A bacterial artificial chromosome (BAC) library was constructed for the MSM/Ms genome, and sequence analysis of the MSM/Ms genome showed approximately 1% of nucleotides differed from those in the commonly used inbred mouse strain, C57BL/6J. Therefore, MSM/Ms mice are thought to be useful for functional genome studies. MSM/Ms mice show unique characteristics of phenotypes, including its smaller body size, resistance to high-fat-diet-induced diabetes, high locomotive activity, and resistance to age-onset hearing loss, inflammation, and tumorigenesis, which are distinct from those of common inbred mouse strains. Furthermore, ES (Embryonic Stem) cell lines established from MSM/Ms allow the MSM/Ms genome to be genetically manipulated. Therefore, genomic and phenotypic analyses of MSM/Ms reveal novel insights into gene functions that were previously not obtained from research on common laboratory strains. Tumorigenesis-related MSM/Ms-specific genetic traits have been intensively investigated in Japan. Furthermore, radiation-induced thymic lymphomas and chemically-induced skin tumors have been extensively examined using MSM/Ms.
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Independent genetic control of early and late stages of chemically induced skin tumors in a cross of a Japanese wild-derived inbred mouse strain, MSM/Ms
Carcinogenesis, 2012Co-Authors: Kazuhiro Okumura, Ryo Kominami, Megumi Saito, Miho Sato, Ikuo Miura, Shigeharu Wakana, Jian-hua Mao, Yuki Miyasaka, Yuichi WakabayashiAbstract:MSM/Ms is an inbred mouse strain derived from a Japanese wild mouse, Mus Musculus Molossinus. In this study, we showed that MSM/Ms mice exhibit dominant resistance when crossed with susceptible FVB/N mice and subjected to the two-stage skin carcinogenesis protocol using 7,12-dimethylbenz(a)anthracene (DMBA)/ 12-O-tetradecanoylphorbol-13-acetate (TPA). A series of F1 backcross mice were generated by crossing p53(+/+) or p53(+/-) F1 (FVB/N × MSM/Ms) males with FVB/N female mice. These generated 228 backcross animals, approximately half of which were p53(+/-), enabling us to search for p53-dependent skin tumor modifier genes. Highly significant linkage for papilloma multiplicity was found on chromosomes 6 and 7 and suggestive linkage was found on chromosomes 3, 5 and 12. Furthermore, in order to identify stage-dependent linkage loci we classified tumors into three categories ( 6mm), and did linkage analysis. The same locus on chromosome 7 showed strong linkage in groups with 6mm, but a different locus on chromosome 4 showed strong linkage both to papillomas >6mm and to carcinomas. This locus, which maps near the Cdkn2a/p19(Arf) gene, was entirely p53-dependent, and was not seen in p53 (+/-) backcross animals. Suggestive linkage conferring susceptibility to carcinoma was also found on chromosome 5. These results clearly suggest distinct loci regulate each stage of tumorigenesis, some of which are p53-dependent.
Masaoki Tsudzuki - One of the best experts on this subject based on the ideXlab platform.
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A Nucleotide Substitution Responsible for the Tawny Coat Color Mutation Carried by the MSKR Inbred Strain of Mice
The Journal of heredity, 2005Co-Authors: A. Wada, Tetsuo Kunieda, M. Nishimura, Y. Kakizoe-ishida, N. Watanabe, K. Ohkawa, Masaoki TsudzukiAbstract:"Tawny" is an autosomal recessive coat color mutation found in a wild population of Mus Musculus Molossinus. The inbred strain MSKR carries the mutation. The causative gene Mc1r[superscript taw] of the tawny phenotype is the second recessive allele at the melanocortin 1 receptor locus and is dominant to the first recessive allele, "recessive yellow" (Mc1r[superscript e]). The Mc1r[superscript taw] gene has six nucleotide substitutions, and its forecasted transcript has three amino acid substitutions (i.e., V101A, V216A, W252C). Though the nucleotide substitutions leading to V101A and V216A exist in various mouse strains, the nucleotide substitution leading to W252C exists in only tawny-colored mice. Thus this substitution is considered to be responsible for the expression of the tawny coat color. The frequency of the allele having this nucleotide substitution was 9.21% in the wild M. m. Molossinus population inhabiting Sakai City, Osaka Prefecture, Japan, where the ancestral mice of the MSKR strain were captured.
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Establishment and Characterization of the MSKR Inbred Strain Originated from Japanese Wild Mice (Mus Musculus Molossinus)
The Journal of veterinary medical science, 2000Co-Authors: Adumi Wada, Hideki Katoh, Masaaki Okumoto, Yuka Kakizoe-ishida, Kaori Muguruma, Michi Ebukuro, Masaoki TsudzukiAbstract:A new inbred strain, MSKR, originated from Japanese wild mice was established in April, 1998. The MSKR mice were 60% of the C57BL/6N inbred mice in the 60-day body weight. Tail length/head-body length and hind-foot length/head-body length of the MSKR mice were significantly smaller than those of the C57BL/6N mice (0.896 vs 1.061, 0.189 vs 0.204), but ear length/head-body length of the MSKR mice was significantly larger than that of the C57BL/6N mice (0.143 vs 0.137). The age of the first parturition and size of the first litter were 63.20 ± 2.71 days and 6.20 ± 0.37, respectively, at the 20th and 22nd inbreeding generations. Genetic characterization of the MSKR strain was performed using 34 microsatellite markers, 29 biochemical markers, 9 immunogenetic markers, 3 coat color markers, and mitochondrial DNA RFLP-haplotypes. The result indicated that this newly established inbred strain has some different gene constitution from already known Molossinus and common laboratory strains.
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Tawny: a novel light coat color mutation found in a wild population of Mus Musculus Molossinus, a new allele at the melanocortin 1 receptor (Mc1r) locus.
Experimental animals, 1999Co-Authors: Adumi Wada, Masaaki Okumoto, Masaoki TsudzukiAbstract:We found a new coat color mutant in a population of Japanese wild mice (Mus Musculus Molossinus) and called the trait tawny. The tawny mutant is characterized by a light yellowish brown coat color. The tawny hair has a so-called agouti pattern, but the yellow band is greatly lengthened. There are no differences between the tawny and wild-type hairs in size and the number of melanosomes. Genetic analyses revealed that the tawny trait is an autosomal recessive and its gene is located in the distal region on Chromosome 8 between the microsatellite markers D8Mit87 and D8Mit122. An allelism test indicated the tawny mutant gene to be a new allele at the Mc1r locus and dominant to the recessive yellow (Mc1re). The proposed gene symbol for the tawny is Mc1rtaw.
Keiji Mochida - One of the best experts on this subject based on the ideXlab platform.
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CRISPR/Cas9-mediated genome editing in wild-derived mice: generation of tamed wild-derived strains by mutation of the a (nonagouti) gene.
Scientific reports, 2017Co-Authors: Michiko Hirose, Ayumi Hasegawa, Keiji Mochida, Shogo Matoba, Yuki Hatanaka, Kimiko Inoue, Tatsuhiko Goto, Hideki Kaneda, Ikuko Yamada, Tamio FuruseAbstract:Wild-derived mice have contributed to experimental mouse genetics by virtue of their genetic diversity, which may help increase the chance of identifying novel modifier genes responsible for specific phenotypes and diseases. However, gene targeting using wild-derived mice has been unsuccessful because of the unavailability of stable embryonic stem cells. Here, we report that CRISPR/Cas9-mediated gene targeting can be applied to the Japanese wild-derived MSM/Ms strain (Mus Musculus Molossinus). We targeted the nonagouti (a) gene encoding the agouti protein that is localized in hair and the brain. We obtained three homozygous knockout mice as founders, all showing black coat colour. While homozygous knockout offspring were physiologically indistinguishable from wild-type litter-mates, they showed specific domesticated behaviours: hypoactivity in the dark phase and a decline in the avoidance of a human hand. These phenotypes were consistent over subsequent generations. Our findings support the empirical hypothesis that nonagouti is a domestication-linked gene, the loss of which might repress aggressive behaviour.
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Efficient Production of Offspring from Japanese Wild-Derived Strains of Mice (Mus Musculus Molossinus) by Improved Assisted Reproductive Technologies
Biology of reproduction, 2012Co-Authors: Ayumi Hasegawa, Keiji Mochida, Shogo Matoba, Kazuya Yonezawa, Akihiko Ohta, Kazuyoshi Taya, Watanabe, Atsuo OguraAbstract:Because the genetic diversity of the laboratory mouse (Mus Musculus) is very limited, wild-derived strains from this genus could provide invaluable experimental models for studies of mouse genetics and epigenetics such as quantitative trait locus analysis. However, such strains generally show poor reproductive performance under conventional husbandry conditions, so their use for large-scale analyses has been limited. This study was undertaken to devise assisted reproductive technologies (ARTs) for the efficient production of offspring in two wild-derived strains, MSM/Ms and JF1/Ms (Mus Musculus Molossinus). First, as females of these strains are poor responders to equine chorionic gonadotropin (eCG) stimulation, we examined the efficiency of superovulation by injecting anti-inhibin serum followed by human chorionic gonadotropin (hCG). Approximately four to six times more oocytes were ovulated than with eCG-hCG treatment in both strains, reaching ;25–30 oocytes per female. Consequently, the procedures for in vitro fertilization using these superovulated oocytes and cryopreservation of embryos and spermatozoa could be optimized for both of the wild-derived strains. However, MSM/Ms embryos but not JF1/ Ms embryos failed to develop to term after embryo transfer because of intrauterine death at mid to late gestation. We were able to overcome this obstacle by cotransfer of these embryos with those from laboratory strains combined with treatment of recipient females with an immunosuppressant (cyclosporin A). Thus, a series of ARTs essential for efficient production and preservation of the wild-derived strains were successfully devised. These technologies will facilitate systematic studies of mouse genetics and epigenetics using a wider range of genetic diversity than currently available in the genus Mus.
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Efficient production of offspring from Japanese wild-derived strains of mice (Mus Musculus Molossinus) by improved assisted reproductive technologies. Biol Reprod 86: 1–7
2012Co-Authors: Ayumi Hasegawa, Keiji Mochida, Shogo Matoba, Kazuya Yonezawa, Akihiko Ohta, Gen Watanabe, Kazuyoshi Taya, Atsuo OguraAbstract:Because the genetic diversity of the laboratory mouse (Mus Musculus) is very limited, wild-derived strains from this genus could provide invaluable experimental models for studies of mouse genetics and epigenetics such as quantitative trait locus analysis. However, such strains generally show poor reproduc-tive performance under conventional husbandry conditions, so their use for large-scale analyses has been limited. This study was undertaken to devise assisted reproductive technologies (ARTs) for the efficient production of offspring in two wild-derived strains, MSM/Ms and JF1/Ms (Mus Musculus Molossinus). First, as females of these strains are poor responders to equine chorionic gonadotropin (eCG) stimulation, we examined the efficiency of superovulation by injecting anti-inhibin serum followed by human chorionic gonadotropin (hCG). Approxi
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Comparison of glycoprotein hormone α-subunits of laboratory animals
Molecular reproduction and development, 2002Co-Authors: Osamu Suzuki, Keiji Mochida, Yoshie Yamamoto, Yoko Noguchi, Kaoru Takano, Junichiro Matsuda, Astuo OguraAbstract:The common α-subunit of glycoprotein hormones (CGα) is a core protein shared by follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH). In order to obtain a molecular basis for an efficient superovulation technique applicable to a wide range of animal species and to discuss the phylogenetic aspect based on molecules related to the reproductive system, we determined cDNA sequences of CGα in seven laboratory animals: the guinea pig, Mongolian gerbil, golden hamster, mastomys, Japanese field vole, the JF1 strain of Mus Musculus Molossinus, and rabbit. Comparison of the inferred CGα amino acid sequences of these animals and other mammals (human, mouse, rat, cow, pig, and sheep) showed that the signal peptides and the first ten residues at the N-terminus of the apoprotein were variable, while the rest of the apoproteins were highly conserved. In particular, all rodents had a leucine residue at the apoprotein N-terminus, except the guinea pig, which had a phenylalanine residue, as in the cow, pig, sheep, and rabbit. Phylogenetic trees constructed from amino acid sequences suggest a closer relationship between the guinea pig and artiodactyls than to rodents, confirming the taxonomic peculiarity of the guinea pig. Mol. Reprod. Dev. 62: 335–342, 2002. © 2002 Wiley-Liss, Inc.
Atsuo Ogura - One of the best experts on this subject based on the ideXlab platform.
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Efficient Production of Offspring from Japanese Wild-Derived Strains of Mice (Mus Musculus Molossinus) by Improved Assisted Reproductive Technologies
Biology of reproduction, 2012Co-Authors: Ayumi Hasegawa, Keiji Mochida, Shogo Matoba, Kazuya Yonezawa, Akihiko Ohta, Kazuyoshi Taya, Watanabe, Atsuo OguraAbstract:Because the genetic diversity of the laboratory mouse (Mus Musculus) is very limited, wild-derived strains from this genus could provide invaluable experimental models for studies of mouse genetics and epigenetics such as quantitative trait locus analysis. However, such strains generally show poor reproductive performance under conventional husbandry conditions, so their use for large-scale analyses has been limited. This study was undertaken to devise assisted reproductive technologies (ARTs) for the efficient production of offspring in two wild-derived strains, MSM/Ms and JF1/Ms (Mus Musculus Molossinus). First, as females of these strains are poor responders to equine chorionic gonadotropin (eCG) stimulation, we examined the efficiency of superovulation by injecting anti-inhibin serum followed by human chorionic gonadotropin (hCG). Approximately four to six times more oocytes were ovulated than with eCG-hCG treatment in both strains, reaching ;25–30 oocytes per female. Consequently, the procedures for in vitro fertilization using these superovulated oocytes and cryopreservation of embryos and spermatozoa could be optimized for both of the wild-derived strains. However, MSM/Ms embryos but not JF1/ Ms embryos failed to develop to term after embryo transfer because of intrauterine death at mid to late gestation. We were able to overcome this obstacle by cotransfer of these embryos with those from laboratory strains combined with treatment of recipient females with an immunosuppressant (cyclosporin A). Thus, a series of ARTs essential for efficient production and preservation of the wild-derived strains were successfully devised. These technologies will facilitate systematic studies of mouse genetics and epigenetics using a wider range of genetic diversity than currently available in the genus Mus.
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Efficient production of offspring from Japanese wild-derived strains of mice (Mus Musculus Molossinus) by improved assisted reproductive technologies. Biol Reprod 86: 1–7
2012Co-Authors: Ayumi Hasegawa, Keiji Mochida, Shogo Matoba, Kazuya Yonezawa, Akihiko Ohta, Gen Watanabe, Kazuyoshi Taya, Atsuo OguraAbstract:Because the genetic diversity of the laboratory mouse (Mus Musculus) is very limited, wild-derived strains from this genus could provide invaluable experimental models for studies of mouse genetics and epigenetics such as quantitative trait locus analysis. However, such strains generally show poor reproduc-tive performance under conventional husbandry conditions, so their use for large-scale analyses has been limited. This study was undertaken to devise assisted reproductive technologies (ARTs) for the efficient production of offspring in two wild-derived strains, MSM/Ms and JF1/Ms (Mus Musculus Molossinus). First, as females of these strains are poor responders to equine chorionic gonadotropin (eCG) stimulation, we examined the efficiency of superovulation by injecting anti-inhibin serum followed by human chorionic gonadotropin (hCG). Approxi
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Expression of imprinted genes in cloned mice.
Methods in molecular biology (Clifton N.J.), 2006Co-Authors: Takashi Kohda, Fumitoshi Ishino, Atsuo OguraAbstract:Genomic imprinting is a mammalian specific epigenetic modification of the genome. Assessment of the integrity of the imprinting memory in somatic cell cloned animals is important not only for understanding of the "reprogramming" process during cloning by nuclear transfer, but also for the applications of this technique for therapeutic cloning in the future. In this chapter, we summarize the analytical methods for assessment of monoallelic expression of imprinting genes and expression analysis. From a practical point of view, the authors suggest the use of intersubspecific F1 hybrids between the laboratory mouse (Mus Musculus Musculus) and the JF1 strain (Mus Musculus Molossinus). We also list the sequence for PCR primers to detect the polymorphism of imprinted genes between Musculus and Molossinus.
