関連する実験動画
Updated: Jul 14, 2026

10:37
Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
小型Gタンパク質Cdc42がACKのGTPーゼ結合ドメインに結合する構造
H R Mott1, D Owen, D Nietlispach
1Cambridge Centre for Molecular Recognition, Department of Biochemistry, University of Cambridge, UK.
Nature
|June 9, 1999
まとめ
Rho GTPases Cdc42 と Rac は,結合エフェクターによって細胞機能を調節する. この研究は,Cdc42とACKの間の新しい複雑な構造を明らかにし,特定の結合相互作用を詳細に説明しています.
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:
- Cdc42とRacは,細胞細胞骨格,分化,増殖を制御するRho GTPaseである.
- PAKキナーゼのようなCRIBタンパク質や,ACKチロシンキナーゼやWASPのような特定のタンパク質を含む下流エフェクターと結合します.
- エフェクタループ (スイッチI) は構造的にダイナミックですが,Cdc42とRacの間で類似しており,エフェクタ特異性は説明できません.
研究 の 目的:
- ACK複合体のCdc42-GTPase結合ドメインの溶液構造を決定する.
- Cdc42とACK.との間の特定の相互作用の基礎となる分子メカニズムを解明する.
主な方法:
- 核磁共振 (NMR) スペクトロスコピーは,溶液の構造を決定する.
- タンパク質とタンパク質の相互作用と形状の変化の分析.
主要な成果:
- 複雑な形成は,Cdc42とACKの両方の重要な形状の変化を誘導します.
- この相互作用は,Ras/エフェクタ相互作用と同様に,Cdc42ベータシートをACK鎖で拡張することを含む.
- Cdc42の追加の領域は,スイッチI領域を超えて,エフェクタ結合の特異性に寄与します.
結論:
- Cdc42とACKの間の新しいGタンパク質/エフェクター複合体の構造が解明されました.
- 結果は,エフェクター特異性は,保存されたエフェクターループ以上のことを含んでいることを明らかにします.
- これは,Rho GTPaseシグナル伝達経路の調節に関する洞察を提供します.
関連する概念動画
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...
Large G-proteins, also known...
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...
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...
Large G-proteins, also known...
Assembly of Signaling Complexes
Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...

