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研究発表を行った学会；
・21st International Mammalian Genome Conference、2007年10月28日~11月1日(京都)

タイトル；Establishment of embryonic stem cell lines derived from MSM/Ms strain originated from Mus musculus molossinus.

発表者；　荒木　喜美　氏
　　　（熊本大学　発生医学研究センター　臓器形成分野）
Abstract；
　The MSM/Ms strain was established from Japanese wild mice, Mus musculus molossinus, collected in 1978 in Mishima, Japan. Comparison of the MSM/Ms sequences with the C57BL/6J revealed that the overall nucleotide substitution rate as high as 0.96%, which was comparable with the genomic difference between humans and chimpanzees (1.23%). MSM/Ms has unique characteristics not observed in the commonly used laboratory strains, for example, extremely low incidence of tumor development, characteristic behavioral phenotypes and resistance to high-fat diet-induced diabetes. Therefore, functional genome analyses in MSM/Ms should provide a means to identifying novel phenotypes and gene functions. We report here the derivation of germline-competent ES cell lines from MSM/Ms blastocysts, allowing the Mus musculus molossinus genome to be genetically manipulated. Using Knockout Serum Replacement (KSR) and Glasgow minimal essential medium (GMEM), we found that we can readily establish ES cell lines from blastocysts. Three lines (Mol/MSM-1, 2 and 3) were established and tested for chimera generation by aggregation with ICR molura. In all three lines, chimeric mice were born, and coat-color chimerism varied from 5-100%. High percentage chimeras were used for in vitro fertilization with ICR oocytes and confirmed germline transmission. We also injected Mol/MSM-1 ES cells into blastosysts of ICR or C57BL/6 X BDF1, and found that injection into C57BL/6 X BDF1 gave higher production rate of chimeric mice. These Mol/MSM ES lines should provide excellent tool for mutagenesis and analyses of phenotypes.