細胞タンパク質のN端アセチル化により,特定の分解信号が生成されます
Cheol-Sang Hwang1, Anna Shemorry, Alexander Varshavsky
1Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
まとめ
タンパク質のN端アセチル化は,真核生物に共通しており,分解のシグナルを与える可能性があります. この研究では,酵母におけるDoa10ユビキチンリガゼによって認識される重要な分解信号 (AcN-デグロン) としてアセチル化されたN端末残基を特定しています.
科学分野:
- 分子生物学は分子生物学である.
- プロテオスタシス プロテオスタシス
- ウビキチン-プロテアゾームシステム
背景:
- N-末端アセチル化 (Nt-アセチル化) は,ヒトのタンパク質の80%以上に影響を与える,ユーカリ生物における一般的な共同翻訳的修正である.
- Nt-アセチル化の機能的意義,特にタンパク質の分解におけるその役割は,ほとんど未研究のままである.
- N末端メチオニン (Met) はしばしばアセチル化され,その後の処理は,アラニン (Ala),バリン (Val),セリン (Ser),スレオニン (Thr),システイン (Cys) などの他のN末端残基のアセチル化につながる可能性があります.
研究 の 目的:
- タンパク質の調節におけるN端子アセチル化の機能的役割を調査する.
- タンパク質の分解のシグナルとして作用する特定のN端末残留物および変異を特定する.
- これらの信号が細胞機械によって認識され,処理されるメカニズムを解明する.
主な方法:
- 酵母Saccharomyces cerevisiaeをモデル生物として利用した.
- N端末変異の認識におけるDoa10ユビキチンリガゼの役割を調査した.
- N末端の分解信号を含むタンパク質を特定するために,プロテオミックおよび遺伝的アプローチを採用しました.
主要な成果:
- N-末端アセチル化メット残基が分解信号 (degron) として機能することを実証した.
- Doa10ユビキチンリゲーゼがNt-アセチル化Met,Ala,Val,Ser,Thr,Cysの残基を認識し,標的にすることを示した.
- 様々な細胞タンパク質に存在する,AcN-degronsと呼ばれる,N-末端の分解シグナルの一流クラスの存在を特定しました.
結論:
- N末端アセチル化は,タンパク質分解の重要な信号として機能し,細胞のプロテオスタシスに寄与する.
- Doa10ユビキチンリガゼは,特定のN末端アセチル化パターンを持つタンパク質の分解を認識し,媒介する上で重要な役割を果たします.
- AcN-degronsは,タンパク質のレベルと細胞内の機能を調節するための広範なメカニズムを表しています.
関連する概念動画
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...
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
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...
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...
Phase II Reactions: Acetylation Reactions
Acetylation, a phase II biotransformation reaction, introduces an acetyl group to drugs or their metabolites. Acetyltransferase enzymes facilitate this reaction, which resembles α-amino acid conjugation due to the addition of a functional group to the drug molecule.
The substrates for acetylation are typically drugs or their metabolites with an amino, sulfonamide, or hydrazine functional group. Acetylation can occur at several points in the drug molecule, including primary, secondary, and...
The substrates for acetylation are typically drugs or their metabolites with an amino, sulfonamide, or hydrazine functional group. Acetylation can occur at several points in the drug molecule, including primary, secondary, and...


