哺乳類における精子の成熟と受精中のtRNA断片の生殖と機能
Upasna Sharma1, Colin C Conine1, Jeremy M Shea1
1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
まとめ
父親の食事は 精子の小さなRNAを通して 子孫の代謝に影響を与えます 食事によるタンパク質の制限は,早期の胚における遺伝子発現を制御する,トランスファーRNAの断片を含む精子の小さなRNAレベルを変化させます.
科学分野:
- エピジェネティクスと発達生物学
- 精子の生物学とRNAの調節
- 子孫フェノタイプの栄養プログラム
背景:
- 親の環境は世代を超えて子孫のフェノタイプに影響を与えることがますます認識されています.
- 父親の食事が子孫の代謝に影響を与える特定のメカニズムは完全に理解されていません.
- 精子の小さなRNA (sRNA) は,このような世代間効果の潜在的な媒介者として関与しています.
研究 の 目的:
- 精子の小さなRNAを介して父親の食事と子孫の代謝のメカニズム的なリンクを調査する.
- 父親の食事中のタンパク質の制限によって引き起こされる精子のsRNA組成の変化を特徴づける.
- 移転RNA断片などの特定のsRNAの機能的役割を胚の発達において決定する.
主な方法:
- 精子のsRNAプロファイルへの影響を評価するために,マウスを食事のタンパク質制限の対象とした.
- 異なる成熟段階の精子におけるレット-7およびトランスファーRNA (tRNA) 断片を含む小RNA (sRNA) レベルの分析
- 精子へのRNAペイロードのキャリアとしてのエピディジモソームの調査.
- 胚性幹細胞と胚を用いた実験で,tRNA断片の機能を評価する.
主要な成果:
- 父のタンパク質の制限により,成熟した精子におけるsRNA濃度が変化し,レット7が減少し,グリシン転送RNA (tRNA) の5'断片が増加した.
- 精巣の精子に希少な tRNA 断片は, epididymal トランジット中に増加し, epididymosomes で発見されました.
- エピディジモソームは,未成熟の精子に特定のRNAのペイロードをインビトロで送った.
- 胚性幹細胞および胚における内生的なレトロエレメントMERVLに関連した抑制された遺伝子のグリシンtRNA断片.
結論:
- 精巣の精子の成熟後の期間に,sRNA生殖の食事による調節が行われます.
- 移転RNA断片は,植入前の胚の内生的なレトロエレメントを調節する役割を果たします.
- 父親の食事は,精子によるRNAを介して子孫に表遺伝子情報を伝達し,胚の遺伝子発現に影響を与えます.
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