関連する実験動画
Updated: Jul 19, 2026
11:42
Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
トリガー因子とDnaKは,新たに合成されたタンパク質の折り畳みに協力する
E Deuerling1, A Schulze-Specking, T Tomoyasu
1Institut für Biochemie und Molekularbiologie, Freiburg, Germany.
Nature
|August 24, 1999
まとめ
誘発因子であるリボソーム関連チャペロンは,E. coliにおけるタンパク質の折り畳みに極めて重要です. Hsp70 DnaKとの協力により,タンパク質の集積を防止し,細胞の生存能力を確保します.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- タンパク質の折りたたみ
背景:
- 新生タンパク質の折りたたみにおける分子チャペロンの役割は完全に理解されていません.
- E. coliでは,GroELとHsp70のDnaKは,適度な温度下での折り畳みに欠かせない.
- リボソーム関連トリガーファクターは,新生ポリペプチドの主要な伴侶である.
研究 の 目的:
- タンパク質の折りたたみにおけるトリガーファクターのインビボ機能を調査する.
- トリガーファクターとDnaKの機能的関係を決定する.
- E. coliにおけるシャペロンの協力的メカニズムを解明する.
主な方法:
- 遺伝子消去変異体 (delta tig::kan) は,E. coliで作られました.
- 組み合わせた変異 (デルタ・ティグ・カーン,デルタ・DNAK) を分析した.
- タンパク質の集積とDnaKとの関連性は,さまざまな条件下で評価されました.
主要な成果:
- トリガーファクタが欠けていた大腸菌は,成長や折り畳み欠陥を示さなかった.
- トリガー因子とDnaK欠乏症の組み合わせは,合成的致死性を引き起こした.
- トリガー因子欠乏細胞におけるDnaKの枯渇は,大量の細胞塩分タンパク質の集積につながった.
結論:
- トリガーファクターは,一般的なタンパク質の折りたたみのためのチャペロン活動を示す.
- トリガー因子とDnaKは,適切なタンパク質の折り畳みと細胞の生存性を確保するために協力します.
- どちらも個別に,中間の成長温度で折りたたみと生存能力のために不可欠ではありません.
関連する概念動画
02:54Nucleosome Remodeling
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
01:02The DNA Replication Fork
An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication forks, one in...
03:01The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
02:37Restarting Stalled Replication Forks
DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...
03:01The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
01:26Bacterial Protein Maturation
Bacterial protein maturation is a tightly regulated process that ensures newly synthesized polypeptides achieve correct functional conformations. This maturation involves a series of modifications, folding events, and quality control steps, often assisted by specialized chaperone proteins.N-Terminal ModificationsThe maturation of bacterial polypeptides begins cotranslationally as the polypeptide exits the ribosome. The first amino acid, N-formylmethionine (fMet), is typically modified at the...