201809Takada

研究発表を行った学会；The international Research Symposium on Regulation of Germ Cell Development in vivo and in vitro.
2017年 7月26日〜28日（福岡）
タイトル；Functional analysis of Polycomb group proteins Ring1A/1B during meiotic prophase.
発表者；高田　幸氏
（熊本大学　発生医学研究所　染色体制御分野）
要旨；
The polycomb repressive complex (PRC) 1 protein Ring1B is a ubiquitin ligase that modifies nucleosomal histone H2A, a modification that plays a critical role in regulation of gene expression. During meiotic prophase I, ubiquitylated histone H2A (uH2A) are distributed in the whole nucleus and enriched on the XY body, a specialized nuclear territory for the sex chromosomes. To clarify the mechanisms linking Ring1B and uH2A during meiotic prophase I and their biological outcomes, we analyzed the phenotypes of spermatocytes from the Ring1A/1B conditional knockout (cko) mice. In the immunofluorescence analysis, we found the disappearance of uH2A from the nucleus of Ring1A/1B-deficient spermatocytes, suggesting that Ring1B is essential for ubiquitylation of H2A during meiotic prophase I. Intriguingly, spermatocytes in the Ring1A/1B cko mice arrested in meiotic prophase I at the zygotene stage with aberrant synapsis and tangled chromosomes at their terminal regions. This study suggests that Ring1A/1B may have a function for homolog pairing and synapsis via chromosome architecture and dynamic movement during mammalian gametogenesis.