Transposable elements (TEs) occupy a large proportion of many eukaryotic genomes and play beneficial effects for the evolution of organisms. However, we do not have a clear understanding of how individual TEs are recognized and regulated in cells. Our laboratory is interested in molecular mechanisms on epigenetic regulations of TEs in Drosophila. To understand them, we are engaged in studying the piRNA pathways, chromatin regulation and germ line development using biochemical and high-throughput technologies, and genetic tools which are managed and distributed by genetic resources project (NIG-Fly).
(A) Schematic representation of piRNA-mediated TE silencing system in Drosophila. (B) Piwi (Green) is expressed in ovarian somatic cells and Vasa-positve (Red) germ cells. (C) Fly strains we are maintaining and providing under the National Bioresource Project.
Iwasaki, Y.W., Murano, K., Ishizu, H., Shibuya, A., Iyoda, Y., Siomi, M.C., Siomi, H., and Saito, K. (2016). Piwi modulates chromatin accessibility by regulating multiple factors including histone H1 to represss transposons. Mol Cell 63, 408-419.
Shibata, N., Kashima, M., Ishiko, T., Nishimura, O., Rouhana, L., Misaki, K., Yonemura, S., Saito, K., Siomi, H., Siomi, M.C., and Agata, K. (2016). Inheritance of a nuclear PIWI from pluripotent stem cells by somatic descendants ensures differentiation by silencing transposons in planarian. Dev Cell 37, 226-237.
Ohtani, H., Iwasaki, Y.W., Shibuya, A., Siomi, H., Siomi, M.C., and Saito K. (2013). DmGTSF1 is necessary for Piwi–piRISC-mediated transcriptional transposon silencing in Drosophila. Genes Dev 27, 1656-1661.