Vol13-1-e47

10/24

10AIST TODAY 2013-1life-liaison-ml@aist.go.jpFor inquiries about this article : Research Planning Office of Life Science and BlotechnologyWe selected human proteome expression resource (HUPEX) from the human cDNA library (http://www.HGPD.jp) to establish a retrovirus expression clone and looked for new iPS cell inducing factors.References[1] M. Maekawa et al.: Nature, 474, 225-229 (2011).[2] N. Goshima et al.: Nature methods, 5 (12), 1011-1017 (2008).[3] http://www.HGPD.jp: Y. Maruyama et al.: Nucleic Acids Res., 40 (D1), D924–D929, (2012).attL1 attL2 ORF attL1 attL2 ORF Human cDNA LibraryHuman cDNA LibraryProduction of full-length human cDNA libraryHuman proteome expression resource(about 60,000 clones)About 80 % of human genes are covered.About 80 % of human genes are covered.All genes: 22,000Incorporated into retrovirus vectorFull-length cDNANew factor candidateScreening of new iPS inducing factors using the libraryDiscovery of Glis1iPS cellsTransfection of Yamanaka’s four or three factors(Oct3/4, Sox2, Klf4, c-Myc)Fibroblast ORFattL2Production of safe iPS cellsIn a joint research with Prof. Shinya Yamanaka, director of the Center for iPS Cell Research and Application, Kyoto University (and joint winner of the 2012 Nobel Prize in Physiology or Medicine), we found that transfection of Glis1 factor into fibroblast together with Yamanaka’s three factors (Oct3/4, Sox2, Klf4) or four factors (Oct3/4, Sox2, Klf4, c-Myc) allows us to efficiently produce far safer iPS cells. [1]Prof. Yamanaka’s group has so far successfully produced iPS cells by transfecting the three or four factors into fibroblast using retrovirus vectors. However, they encountered some problems, including the risk of cancer formation, presumably due to the influence of the transfected factor c-Myc, as well as an extremely low establishment rate of iPS cell without c-Myc. Practical use of iPS cells in regenerative medicine still requires the solution of these problems. We looked for new iPS cell inducing factors to establish a method for the efficient production of iPS cells safe enough for clinical application. We used the world’s largest human cDNA library created so far, which has been built by us, in our search for appropriate factors.[2]Utilization of human cDNA libraryWe selected 1,437 transcription factors from the human cDNA library,[3] as mentioned above, and looked for new iPS cell inducing factors. Conventional iPS cell inducing factors were found in genes that are frequently expressed in ES cells. However, we decided not to simply follow the past successes and looked for new factors from a comprehensive library. As a result, we found a new iPS cell inducing factor, Glis1. Almost none of the functions of Glis1 have been clarified. It is therefore a gene with no known functions. In addition, it is rarely expressed in ES cells. Thus, no researchers have listed it even as a candidate for initialization factors. When transfected into fibroblast of a mouse or a human together with Yamanaka’s three or four factors, Glis1 can efficiently induce quality iPS cells. In addition, chimera mice produced from iPS cells using Glis1 showed no occurrence of conspicuous tumors or signs of shorter lifespan as seen in the case of production with c-Myc.Future scheduleTransfection of Glis1 has a possibility of efficiently producing highly safe iPS cells as demonstrated by our research, and is expected to make a great contribution to the establishment of a clinically applicable iPS cell production method. We intend to use the human cDNA library that we have created so as to establish production techniques for various differentiation-induced cells in the future.Discovery of New iPS Cell Inducing Factor, Glis1 Biological Systems Control TeamBiomedicinal Information Research CenterNaoki GOSHIMA

※このページを正しく表示するにはFlashPlayer9以上が必要です