核孔関連TREX-2複合体は,遺伝子発現を調節するメディエーターを使用する
Maren Schneider1, Doris Hellerschmied2, Tobias Schubert1
1Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
Cell
|August 29, 2015
まとめ
TREX- 2複合体はメディエーター複合体と相互作用し,遺伝子転写とmRNA輸出を調節する. この発見は,核毛孔複合体が,転写とRNA処理を結びつけることで,遺伝子発現にどのように影響を与えるかを明らかにしています.
科学分野:
- 分子生物学
- 細胞生物学
- 遺伝子規制
背景:
- 核孔複合体 (NPC) は,核と細胞質の間の輸送を調節する.
- NPCのバスケットに位置するTREX-2複合体は,遺伝子発現,転写,およびmRNAの輸出に影響を与えます.
- TREX-2が遺伝子発現機構を制御する正確なメカニズムは不明である.
研究 の 目的:
- TREX-2複合体が遺伝子発現を調節するメカニズムを解明する.
- TREX- 2とRNAポリメラーゼII (Pol II) の重要な調節体であるメディエーター複合体の相互作用を調査する.
主な方法:
- TREX-2とMediatorの相互作用領域を特定するための構造的および生化学的研究.
- Cdk8キナーゼによるメディエーター複合体の解析
- Pol IIの募集とリン酸化の評価
- TREX-2とMed31の相互依存性を評価するためのトランスクリプトームとフェノタイプのプロファイリング.
- mRNAの輸出におけるTREX-2の役割の調査
主要な成果:
- TREX-2は,保存された領域を介して,メディエーター Med31/Med7N サブモジュールに直接結合する.
- TREX-2は,Cdk8キナーゼによるメディエーターアセンブリを調節する.
- TREX-2はPol II募集とサイト固有のリン酸化に不可欠です.
- TREX-2とMed31は特定の遺伝子の 機能的相互依存を示しています
- TREX-2は,そのメディエーターと相互作用する表面を使用して,mRNAの輸出を制御し,転写とmRNAの処理をリンクします.
結論:
- TREX-2は,メディエーター複合体を通じてコアトランスクリプション機構にアクセスするアダプタ複合体として機能する.
- TREX-2は,早期のmRNA処理ステップと転写開始を統合する.
- この研究は,NPC関連因子が遺伝子発現をどのように調節するかについてのメカニズム的洞察を提供します.
関連する概念動画
Regulation of Nuclear Protein Sorting
3.5K
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
3.5K
Nuclear Export
5.2K
The nucleus restricts several proteins within and allows others to pass. The restricted proteins possess a nuclear retention sequence or NRS, anchoring them to the nuclear lamins and preventing their transport to the cytosol. The non-restricted proteins, after their synthesis, are transported to their site of action, such as the cytosol or other organelles, with the help of nuclear export signals or NES.
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
5.2K
Nuclear Protein Sorting
6.6K
Nuclear protein sorting is the selective trafficking of histones, polymerases, gene regulatory proteins into the nucleus and exporting RNAs and ribosomes to the cytosol. It is a tightly controlled process that regulates gene expression within a cell.
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
Proteins targeted to the nucleus carry nuclear localization signals or NLS recognized by import receptors in the cytosol. Similarly, proteins with nuclear export signals are recognized by export receptors. Import and export receptors are...
6.6K
Nuclear Export of mRNA
9.2K
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
9.2K
Nuclear Export of mRNA
5.6K
5.6K
Directionality of Nuclear Transport
5.1K
Ras-related nuclear protein or Ran is a small G protein that cycles between its GTP and GDP bound states. Ran specific regulators, a Ran GTPase Activating Protein or RanGAP present in the cytosol and a Ran guanine nucleotide exchange factor or RanGEF present inside the nucleus regulate GTP/GDP exchange. A high concentration of GTP inside the cells, in addition to this asymmetric distribution of Ran-specific regulators, leads to a higher RanGTP concentration inside the nucleus. This...
5.1K


