関連する実験動画
Updated: Jul 13, 2026

11:36
In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
Ubiquitinのようなタンパク質チオエステルスイッチの基礎として,E1-E2親和性を切り替えるE1-E2親和性を切り替える.
Danny T Huang1, Harold W Hunt, Min Zhuang
1Howard Hughes Medical Institute, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Nature
|January 16, 2007
まとめ
この研究は,ユビキチン状タンパク質 (UBL) 結合酵素が,チオエステルメカニズムを通じて結合親和性を切り替える方法を明らかにしています. この形状の変化は,UBLの改変経路の連続的なステップを駆動する.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 分子細胞生物学 分子細胞生物学
背景:
- ユービキチン型タンパク質 (UBL) は,ダイナミックなE1-E2-E3酵素カスケードによって変化します.
- E1酵素は,アデニル化によってUBLを活性化し,その後の結合ステップに不可欠なチオエステル中間物質を形成します.
研究 の 目的:
- 人間のNEDD8経路内でUBLの活性化と移転の構造的メカニズムを解明する.
- 酵素基板相互作用と構成変化が,UBL結合カスケードをどのように駆動するかを理解するために.
主な方法:
- 閉じ込められたUBL活性化複合体の構造分析報告.
- NEDD8 E1酵素 (APPBP1-UBA3) を含む複合体,NEDD8の2つの分子,不活性なE2酵素 (Ubc12) とMgATPを使用しました.
主要な成果:
- E1-E2の親和性を調節する"チオエステルスイッチ"メカニズムを特定しました.
- E1へのNEDD8のチオエステル結合に依存する2つのE2結合部位を明らかにし,一つはE1の構成変化によってマスクを外した.
- NEDD8のE2への移行がE1の適合逆転を誘導し,製品放出を促進することを実証しました.
結論:
- 結合酵素間のチオエステル結合の移転は,形状の変化を誘発し,相互作用ネットワークを変化させます.
- このメカニズムは,UBL結合カスケードの連続したステップを推進するために不可欠です.
関連する概念動画
Covalently Linked Protein Regulators
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.
Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The Proteasome
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...
Regulated Protein Degradation
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...
The Proteasome
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 (ubiquitin...
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 (ubiquitin...
The Proteasome Structure
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...

