2019/05/31
Keio University School of Medicine
A research group from the Keio University School of Medicine's Department of Obstetrics and Gynecology (Obstetrics), led by Senior Lecturer Mitsutoshi Yamada, Assistant Professor Seiji Ogawa (at the time of the research, now Deputy Director of the Second Department of Obstetrics and Gynecology at Nasu Red Cross Hospital), and Senior Lecturer Toshio Hamatani, in a joint research project with Deputy Director Akihiro Umezawa, Department Director Hidenori Akutsu, and Section Chief Kenji Miyado of the National Center for Child Health and Development, has identified the gene Zscan5b, which is expressed during the process of establishing ES cells from zygotes. Through studies using a mouse model, they have revealed that Zscan5b stabilizes chromosome structure and contributes to genomic stability in ES cells through DNA damage repair during mitosis.
ES cells, established from zygotes, and iPS cells, established from somatic cells, both possess undifferentiated potential and pluripotency, and are expected to have clinical applications in cell therapy and disease models. However, the chromosomal abnormalities frequently observed in zygotes and stem cells pose a barrier to the realization of safe assisted reproductive technology and regenerative medicine.
The joint research group revealed that the loss of function of the Zscan5b gene induces random chromosomal abnormalities in somatic cells and ES cells, and that DNA damage is not repaired despite the increased expression of DNA repair genes (Rad51l3, Bard1).
Furthermore, they obtained results suggesting that Zscan5b binds to histone H1, stabilizing the chromatin structure, and contributes to genomic stabilization in ES cells through DNA damage repair during the process of mitosis.
These findings are expected to greatly contribute to the realization of safer assisted reproductive technology and regenerative medicine through the development of healthy zygotes and the establishment of stem cells.
The results of this research were published in the online edition of "Stem Cell Reports," the official scientific journal of the International Society for Stem Cell Research (ISSCR), at 11:00 a.m. on May 30, 2019 (U.S. Eastern Time).
For the full press release, please see below.