ダイナミンのGTPase活性と,その結果生じる形状の変化は,エンドサイトーシスにとって不可欠である

B Marks¹, M H Stowell, Y Vallis

¹MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.

Nature

|March 10, 2001

まとめ

ダイナミン・ダイナミンは

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.

背景:

ダイナミンは,クラトリン媒介性内分細胞症と膀の密輸に不可欠なGTPaseである.
膀分裂におけるその正確な役割は不明であり,理論は,それが調節剤として作用することを示唆している.

研究の目的:

ドナミンの機能的要求をエンドサイトーシスで調査する.
膀分裂におけるダイナミンのGTPaseとエフェクタードメインの特定の役割を明らかにする.

主な方法:

ダイナミンのGTPaseエフェクター (GED) とGTPaseドメインにおける点変異体の分析.
endocytosisにおけるダイナミンの機能のインビボ評価.

主要な成果:

ダイナミンのオリゴメリゼーションとGTP結合だけでは,エンドサイトーシスには不十分です.
効率的なGTP水解と形状の変化は,ダイナミンの機能に不可欠です.
これらの発見は,ダイナミンが膀分裂に機械化学的役割を果たしていることを示しています.

結論:

膀分裂におけるダイナミンの機能は機械化学的であり,GTPの水解と形状の変化を必要とする.
単純なGTP結合とオリゴメリゼーションは,ダイナミンのエンドサイトーシスにおける役割を完全に説明することはできません.

さらに関連する動画

13:51

Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay

Published on: November 11, 2018

10:19

Single-Molecule FRET Imaging for Observing the Conformational Dynamics of Dynamin-Like GTPase Atlastin

Published on: January 24, 2025

関連する概念動画

02:14

GTPases and their Regulation

Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...

01:58

Mechanical Protein Functions

Proteins perform many mechanical functions in a cell. These proteins can be classified into two general categories- proteins that generate mechanical forces and proteins that are subjected to mechanical forces. Proteins providing mechanical support to the structure of the cell, such as keratin, are subjected to mechanical force, whereas proteins involved in cell movement and transport of molecules across cell membranes, such as an ion pump, are examples of generating mechanical force.

01:32

Pinching-off of Coated Vesicles

Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...

01:33

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...

02:14

GTPases and their Regulation

01:25

Rab Cascades

Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.

関連する実験動画