哺乳類生殖細胞の減数分裂におけるクロマチン制御とシグナル伝達のクロストーク

哺乳动物生殖细胞减数分裂过程中染色质调控和信号转导之间的串扰

• 批准号: 13J05801
• 负责人: 林 瑛理
• 金额: $ 1.41万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2013
• 资助国家: 日本
• 起止时间: 2013-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13J05801/
• 关键词: 減数分裂; 配偶子形成; 生殖細胞; 哺乳類胚発生; 細胞増殖; タンパク質キナーゼ; 細胞内シグナル伝達; クロマチン制御; 生殖細包; クロマチン動態; ゲノム維持修復; 発生異常; リン酸化プロテオミクス; 遺伝子改変動物

本研究は哺乳類の減数分裂におけるクロマチン状態の時空間的制御を中心とした分子ネットワークの解明を目的とし,機能未知の2遺伝子E20(仮称)及びHfm1其々についてノックアウトマウスを作成しその表現型及び遺伝子機能の解析を進めてきた.前年度にE20-/-マウスの表現型として発生中期までに始まる胚体及び胎盤の矮小化と周産期致死性を確認したが,例外的に成体まで生き延びたE20-/-個体が本年度迄に雄2匹得られた.この2匹の組織学的解析の結果顕著な精巣の萎縮と,体細胞分裂期精原細胞を含む全分化段階の精細胞数,特に円形精子細胞以降のステージの精細胞数の著しい減少が確認された(但し極少数ながら伸張精子細胞も見られ,蛍光標識PNA染色により先体の形成も確認できる).更に発生後期胚生殖巣の免疫蛍光染色の結果, E18.5 E20-/-精巣とE16.5, E18.5 E20-/-卵巣でMVH陽性細胞数の明瞭な減少が観察され, E20が胚発生に加え生殖細胞発生にも重要であることを初めて明らかにした. 然し成体精巣と発生後期胚卵巣共に生殖細胞核でSCP3, SCP1, γH2AX, ATM, ATR, CHK1, CHK2, DNA-PKcs等主要な減数分裂関連タンパク質の時空間的発現パターンやリン酸化修飾に有意な差は見られなかった.その他, E10.5胚由来MEFsの遺伝毒性剤に対する用量反応関係や, 妊娠初期の母マウスへの遺伝毒性剤投与の胚発生への影響について比較した結果, E20-/-胚及びE20-/- MEFs共, hydroxyurea感受性が上昇する可能性を示唆する予備的なデータを得た. 又E13.5胚由来E20-/- MEFsの培養では細胞形態の変化(細胞老化の特徴として知られる扁平で巨大な細胞形態)と増殖停止までにかかる継代数の低下する傾向が見られた. これらの観察事実を踏まえ, 同MEFsの細胞周期や細胞増殖, DNA損傷応答について更なるデータの取得を続けると共に, 細胞老化様の変化に関連する分子経路も視野に加え, E20の寄与する分子ネットワークを明らかにするべく生化学解析を進める.

In this study, mammalian mitosis is involved in the control of the state of time and space. In this study, the control center of mammalian meiosis, the control center of time and space, the control center of the computer, the machine, the computer, the computer, the computer In the previous year, the death of embryo body and dwarfing cycle was confirmed in the previous year, and the exception was that the adult animal was born in the second half of the year, and the male won two pounds this year. The results of histological analysis showed that the spermatozoa during somatic cell division contained the number of fully differentiated spermatozoa, and the number of spermatozoa in the special shape of spermatozoa in order to reduce the number of spermatozoa in order to reduce the number of spermatozoa (but a very small number of sperm cells were found to be confirmed by PNA staining). The results of immuno-fluorescent staining of postnatal embryo germ cells showed that E18.5 E20-spermatozoa E16.5, E18.5 E20-oocyte MVH cells had a clear understanding of the number of sexual cells, and E20 embryos plus reproductive cells were very important. However, SCP3, SCP1, γ H2AX, ATM, ATR, CHK1, CHK2, DNA-PKcs and other major genes in the nuclei of postnatal embryos of adult spermatozoa are intentionally modified by acidification. In the first trimester of pregnancy, the toxicity of MEFs and E10.5 embryos were compared with those of embryos in the first trimester of pregnancy, the results were compared with those of embryos in the first trimester of pregnancy, the results were compared with those of embryos in the first trimester of pregnancy, the results were compared with those of embryos in the first trimester of pregnancy, the results were compared with those of embryos in the first trimester of pregnancy, and the results were compared with those of embryos in the first trimester of pregnancy. The results were compared with those of embryos in the first trimester of pregnancy, the results of which were compared with those of embryos in the first trimester of pregnancy, and the results were compared with those of embryos in the first trimester of pregnancy. the results were compared with those of embryos in the first trimester of pregnancy, and the results were compared with those of embryos in the first trimester of pregnancy The origin of E13.5 embryo is E20, which is called "MEFs". "Cell aging" is characterized by "cell aging", "cell aging", "flat", "huge"cell", "stop colonization", "low algebra", "low algebra". In the same way as MEFs, cell cycle analysis, DNA response, cell aging, molecular pathway, molecular pathway, and biochemical analysis were studied.