迅速なE2-E3の組立と分解により,クリン-RINGのユビキチンリガース基板のプロセシブユビキティレーションが可能になります
Gary Kleiger1, Anjanabha Saha, Steven Lewis
1Howard Hughes Medical Institute and the Division of Biology, 156-29, California Institute of Technology, Pasadena, CA 91125, USA.
Cell
|December 1, 2009
まとめ
ユビキチン-プロテアソーム系は,分解のためにポリユビキチン鎖を必要とします. 研究者らは,Cdc34とSCFリガゼの間の静電相互作用が,ダイナミックでプロセス性鎖合成を可能にし,関連する酵素にわたって保存される可能性が高いメカニズムであることを発見しました.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- タンパク質の分解は,細胞の機能に不可欠です.
- ユビキチン-プロテアゾーム系 (UPS) は,ポリユビキチン鎖を介してタンパク質を分解する.
- プロセス性ポリユビキチン鎖合成のメカニズムは不明である.
研究 の 目的:
- テンプレート独立のプロセス性ポリユビキチン鎖合成の構造的および機械的基礎を解明する.
- チェーンアセンブリにおけるユビキチンリガゼSCFとユビキチン結合酵素Cdc34の役割を調査する.
主な方法:
- Cdc34とCul1.1の初期ドッキングシミュレーションを行いました.
- タンパク質の相互作用を確認するためのクロスリンク実験.
- ミュータント酵素の運動分析.
主要な成果:
- Cdc34は,ナノモラー親和性を持つSCFと結合し,高度にダイナミックな複合体を形成します.
- Cdc34の酸性尾とSCFのCul1サブユニットの間の静電相互作用は,迅速な結合を促進します.
- ミュータントの分析とクロスリンクは,Cdc34の尾とCul1の基本的な峡谷との相互作用を確認した.
- 基本キャニオンに保存された残留物は,クリン-RINGユビキチンリガゼの間で保存されたメカニズムを示唆しています.
結論:
- 静電力によって引き起こされるCdc34とSCFのダイナミックな相互作用により,プロセシブユビキチン鎖合成が可能になります.
- このメカニズムは,クリン-RINGユビキチンリガゼの間で保存され,タンパク質分解経路に影響を与える可能性が高い.
- これらのメカニズムを理解することで,タンパク質のターンオーバーと細胞のプロセスを調節する洞察が得られます.
関連する概念動画
Covalently Linked Protein Regulators
8.2K
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein....
These groups modify specific amino acids in a protein....
8.2K
The Proteasome
7.8K
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
7.8K
Regulated Protein Degradation
6.6K
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
6.6K
Intralumenal Vesicles and Multivesicular Bodies
4.0K
Intraluminal vesicles (ILVs) are small vesicles 50-80 nm in diameter formed during the maturation of early endosomes. A specialized endosome containing numerous ILVs is called a multivesicular body (MVB). ILVs contain internalized molecules such as antigens, nucleic acids, proteins, and metabolites. Some of these molecules are released from the MVBs inside exosomes and are transported to other cells. Other MVBs contain molecules that are retained in the ILVs and are later degraded within the...
4.0K
Anaphase Promoting Complex
2.5K
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
2.5K
The Proteasome
1.6K
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
1.6K


