Articles by Satoshi Funaya in JoVE
Zygotic Fluorescence Recovery After Photo-bleaching Analysis for Chromatin Looseness That Allows Full-term Development Masatoshi Ooga1,3, Satoshi Funaya2, Fugaku Aoki2, Teruhiko Wakayama1,3 1Faculty of Life and Environmental Sciences, Department of Biotechnology, University of Yamanashi, 2Department of Integrated Bioscience, Graduate School of Frontier Sciences, University of Tokyo, 3Advanced Biotechnology Center, University of Yamanashi Chromatin looseness appears to be involved in the developmental potential of blastomeres. However, it is not known whether chromatin looseness can be used as a reliable index for the developmental potential for embryos. Here, an experimental system in which chromatin looseness-evaluated zygotes can develop to full term has been described.
Other articles by Satoshi Funaya on PubMed
Regulation of Zygotic Gene Activation by Chromatin Structure and Epigenetic Factors The Journal of Reproduction and Development. Aug, 2017 | Pubmed ID: 28579579 After fertilization, the genomes derived from an oocyte and spermatozoon are in a transcriptionally silent state before becoming activated at a species-specific time. In mice, the initiation of transcription occurs at the mid-one-cell stage, which represents the start of the gene expression program. A recent RNA sequencing analysis revealed that the gene expression pattern of one-cell embryos is unique and changes dramatically at the two-cell stage. However, the mechanism regulating this alteration has not yet been elucidated. It has been shown that chromatin structure and epigenetic factors change dynamically between the one- and two-cell stages. In this article, we review the characteristics of transcription, chromatin structure, and epigenetic factors in one- and two-cell mouse embryos and discuss the involvement of chromatin structure and epigenetic factors in the alteration of transcription that occurs between these stages.
Chd9 Mediates Highly Loosened Chromatin Structure in Growing Mouse Oocytes Biochemical and Biophysical Research Communications. Jun, 2018 | Pubmed ID: 29665362 During oogenesis, oocytes prepare for embryonic development following fertilization. The mechanisms underlying this process are still unknown. Recently, it has been suggested that a loosened chromatin structure is involved in pluripotency and totipotency in embryonic stem (ES) cells and early preimplantation embryos, respectively. Here, we explored chromatin looseness in oocytes by fluorescence recovery after photobleaching (FRAP) using enhanced green fluorescent protein-tagged histone H2B. The results indicated that the chromatin in growing oocytes was already highly loosened to a level comparable to that in early preimplantation embryos. To elucidate the mechanism underlying the loosened chromatin structure in oocytes, we focused on chromodomain helicase DNA binding protein 9 (Chd9), which is highly expressed in growing oocytes. The oocytes from Chd9 knockout mice (Chd9) generated using the CRISPR/Cas9 system exhibited a less loosened chromatin structure than that of wild-type mice, suggesting that Chd9 is involved in the loosened chromatin structure in growing oocytes. These results suggest that a loosened chromatin structure, which is mediated by Chd9, is a prerequisite for the acquisition of totipotency after fertilization.