トリトラックスによって促進されるbxd非コーディングRNAのトランスクリプションは,トランスクリプションの干渉によってcis内のUbxを抑制する
Svetlana Petruk1, Yurii Sedkov, Kristen M Riley
1Department of Biochemistry, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Cell
|December 19, 2006
まとめ
ビソラキソイド (bxd) 領域から転写された長いノンコーディングRNA (ncRNA) は,驚くべきことにUltrabithorax (Ubx) 遺伝子発現を抑制する. この抑制は,cisにおけるncRNA転写を通じて発生し,トリソラックス複合体TAC1によって媒介されます.
科学分野:
- 発達生物学 発達生物学について
- 遺伝子規制 遺伝子規制
- ノンコーディングRNA 生物学
背景:
- 長いノンコーディングRNA (ncRNA) は,ゲノムの大きな部分から転写されます.
- ビトラクソイド (bxd) ncRNAsは,以前は,トリトラクス群 (trxG) タンパク質を勧誘することによって,Ultrabithorax (Ubx) 発現を活性化すると考えられていた.
- Ubx発現の調節におけるbxd ncRNAsの正確な役割は不明でした.
研究 の 目的:
- Ubx発現の調節におけるbxd ncRNAの役割を調査する.
- bxd ncRNA が Ubx 転写に影響を与えるメカニズムを解明する.
- bxd ncRNAs,Ubx,およびTrithorax複合体との相互作用を理解するために.
主な方法:
- ドロソフィラの胚およびイメージナルディスクにおけるUbxおよびbxdncRNAの非重複表現パターンの分析.
- 小型の干渉RNA (siRNA) またはマイクロRNA (miRNA) 媒介による抑制を排除するための調査.
- UbxとbxdのncRNA発現に関連したトリソラックス複合体 (TAC1) の結合パターンの検討.
主要な成果:
- UbxとbxdのncRNAは,重複しない発現パターンを表しており,ncRNAの抑圧的な役割を示唆しています.
- bxd ncRNAsによるUbx抑制は,siRNAまたはmiRNA経路とは独立しています.
- ncRNAのトランスクリプションはcisで作用し,Ubxのトランスクリプションを抑制する.
- トリソラックス複合体 (TAC1) は,Ubxが発現したときにUbxのコーディング領域と,Ubxが抑制されたときにbxd領域を結合します.
結論:
- 以前の仮説とは対照的に,bxd ncRNAsは,Ubx発現を活性化するのではなく抑制する.
- ncRNAのトランスクリプションそのものが,cisで作用し,Ubx抑制のメカニズムである.
- TAC1は,bxd ncRNAの延長を促進することによって,Ubxのモザイク表現パターンを促進し,Ubxの転写抑制につながります.
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