Title:
DNA methylation of retrotransposons by small non-coding RNAs

 

Speaker:
Toru Nakano
Department of Pathology, Medical School and Faculty of Frontier Biosciences, Osaka University

 

Abstract:
Non-coding RNAs have emerged as one of the important gene expression regulation mechanisms. There are three classes of small non-coding RNAs, namely, miRNA (microRNA) siRNA (short interfering RNA), and germ cell specific piRNA (PIWI-interacting RNA). PIWI family is a gene family well-conserved from C. elegans to human and there are three mouse PIWI family members, MIWI (mouse piwi), MILI (miwi like), and MIWI2. We started the study of mouse PIWI family proteins about twenty years ago and have revealed several aspects of the functions of mouse PIWI family proteins and piRNAs 1. MILI and MIWI2 are necessary for spermatogenesis (1) and contribute to the production of piRNAs (2, 3). 2. piRNAs in embryonic male germ cells are mainly derived from retrotransposon genes and play critical roles in de novo DNA methylation of retrotransposons (3). 3. MIWI2 is a critical factor in the complex for the de novo DNA methylation machinery (4). In addition, we established an experimental system to introduce artificial piRNA production and subsequent gene silencing in the male germ cells (5). In this seminar, I will talk about the history and summary of these projects.

 

References:
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2.Aravin A, Gaidatzis D, Pfeffer S, Lagos-Quintana M, Landgraf P, Iovino N, Morris P, Brownstein MJ, Kuramochi-Miyagawa S, , Nakano T, Chien M, Russo JJ, Ju J, Sheridan R, Sander C, Zavolan M, Tuschl T. Nature, 442:203-7, 2006
3.Kuramochi-Miyagawa S, Watanabe T, Gotoh K, Totoki Y, Toyoda A, Ikawa M, Asada N, Kojima K, Yamaguchi Y, Ijiri T, Hata K, Li E, Matsuda Y, Kimura T, Okabe M, Sakaki Y, Sasaki H, Nakano T. Genes Dev, 22:918-30, 2008
4.Kojima-Kita K, Kuramochi-Miyagawa S, Nagamori I, Ogonuki N, Ogura A, Hasuwa H, Akazawa T, Inoue N, Nakano T. Cell Rep, 16:2819-2828, 2016
5.Itou D, Shiromoto Y, Shin-ya Y, Ishii C, Nishimura T, Ogonuki N, Ogura A, Kuramochi-Miyagawa, Nakano T. Current Biol, 25: 901-906, 2015