関連する実験動画
Updated: Jul 3, 2026

10:40
Analysis of Group IV Viral SSHHPS Using In Vitro and In Silico Methods
Published on: December 21, 2019
ESCRT-IIIの螺旋構造は,VPS4によって分解されます
Suman Lata1, Guy Schoehn, Ankur Jain
1Unit for Virus Host Cell Interaction, UMR 5233 UJF (Université Joseph Fourier)-EMBL (European Molecular Biology Laboratory)-CNRS, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9, France.
まとめ
プロテインCHMP2AとCHMP3の輸送 (ESCRT) に必要なエンドソーム分類複合体は,膜の芽生えを促進する螺旋状チューブを形成します. AAA型ATPase VPS4はこれらの構造を分解し,膀形成を制御する.
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:
- トランスポート (ESCRT) 機械に必要な内体ソルティング複合体は,膜改造イベントに不可欠です.
- ESCRTタンパク質は,多胞体形成,ウイルス芽生え,細胞運動などのプロセスを媒介する.
研究 の 目的:
- ESCRT-IIIタンパク質CHMP2AとCHMP3のインビトロ組立と機能を調査する.
- ESCRTによる構造の解体におけるVPS4の役割を明らかにする.
主な方法:
- CHMP2AおよびCHMP3タンパク質のインビトロアセンブリアッセイ.
- CHMP2A/CHMP3コポリメリゼーションと膜結合の分析.
- CHMP2A/CHMP3管のVPS4媒介による解体に関するインビトロ研究.
主要な成果:
- CHMP2AとCHMP3は,外部膜の相互作用部位を持つ螺旋状チューブに自己組み立てられます.
- CHMP2AとCHMP3の共ポリメリゼーションにより,膜標的化が強化されます.
- VPS4はこれらの管の内部に結合し,ATPの水解によってそれらを分解します.
結論:
- 螺旋型のCHMP構造は,芽生えた膀の首の中で形成され,膜分裂を誘発する.
- VPS4は,これらの構造の分解を制御し,膜の再編成を完了するレギュレーターとして機能します.
関連する概念動画
Intralumenal Vesicles and Multivesicular Bodies
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...
Coat Assembly and GTPases
Vesicles incorporate different coat protein subunits in different cell locations, which changes the properties of the coat, such as the shape and geometry of the transport vesicles. Thus, vesicle coat proteins also play a significant role in cargo selection.
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Export of Misfolded Proteins out of the ER
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
Disassembly of Intermediate Filaments
Intermediate filaments (IFs) do not undergo spontaneous disassembly. Enzymes, kinases, and phosphatases add and remove phosphates from specific sites to regulate their disassembly. The IF concentration in the cytoplasm also regulates the disassembly. If the concentration crosses a threshold, it activates the protein kinases in the vicinity, allowing the phosphorylation of IFs.
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Tail-anchoring of Proteins in the ER Membrane
Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
Vesicular Tubular Clusters
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...

