ヒストンH1および他の小さな核愛性タンパク質の核輸送を容易にした
1Department of Biology, University of Rochester, New York 14627.
Cell
|March 23, 1990
まとめ
小さなタンパク質は細胞核に侵入できますが,核局所信号 (NLS) を含むタンパク質は,拡散ではなく受容器媒介の輸送に依存しています. 冷却またはエネルギーの枯渇は,このプロセスを停止し,規制された核輸入メカニズムを明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- 核の輸入は,細胞の機能にとって極めて重要です.
- 核局所信号 (NLS) は,核へのタンパク質輸送を媒介する.
- NLSを含むタンパク質と小タンパク質の輸送を制御するメカニズムは完全に理解されていません.
研究 の 目的:
- 小型の非核タンパク質とNLSを含むタンパク質の細胞核への輸送メカニズムを調査する.
- 原子力の輸入におけるセルエネルギー状態と温度の役割を決定する.
- ヒストンH1とNLS-ペプチド結合体が利用する特定の経路を解明する.
主な方法:
- 様々なタンパク質を細胞細胞質に微量注入する.
- 細胞の冷却とエネルギーの枯渇は,輸送を妨害する.
- 受容体相互作用を分析するためのインサイト定位試験.
主要な成果:
- 小さな非核タンパク質が,冷やされた細胞またはエネルギー不足の細胞の核に拡散しています.
- 大量のNLSを含むタンパク質の輸送が冷却またはエネルギー枯渇によって停止されました.
- NLSを含む小さなタンパク質 (ヒストーンH1,NLS-サイトクロームc) の輸送も停止され,受容体媒介が示唆されました.
結論:
- ヒストンH1および他の小さなNLSを含むタンパク質の核輸入は受容体媒介であり,純粋に拡散的ではありません.
- 細胞質受容体は,ヒストンの核輸入を調節する役割を果たします.
- これらの発見は,NLSを持つ小さな分子でも,核の局所化のための規制されたプロセスを強調しています.
関連する概念動画
02:10The Nucleosome Core Particle
12.2K
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
12.2K
02:54Nucleosome Remodeling
8.7K
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...
8.7K
01:34Nuclear Protein Sorting
4.8K
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...
4.8K
01:42Nuclear Export
3.7K
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...
3.7K
01:45Regulation of Nuclear Protein Sorting
2.5K
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...
2.5K
01:12The Nucleosome Core Particle
2.6K
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
2.6K