Rab GDP-解離阻害剤の構造と変異分析
1Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Nature
|May 2, 1996
まとめ
牛のRab GDP分裂阻害剤 (GDI) の結晶構造は,その2ドメインの組織性を明らかにしています. ラブタンパク質の結合に欠かせない重要な領域は,構造分析と突然変異を介して特定されました.
科学分野:
- 構造生物学 構造生物学とは
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- Rab GDP-解離阻害剤 (GDI) は,膀-膜輸送におけるRab GTPasesの調節に不可欠である.
- GDIの構造を理解することは,Rabタンパク質のリサイクルと機能を明らかにするために不可欠です.
研究 の 目的:
- 牛のアルファ-GDIの高解像度結晶構造を決定する.
- ラブタンパク質の相互作用に関与する構造的特徴を特定する.
主な方法:
- 牛のアルファ-GDI.の1.81A解像度構造を決定するためのX線結晶学.
- サイト・ディレクテッド・ミュータジェネシスで,ラブ結合における保存された領域の役割を調査する.
主要な成果:
- GDIの構造は,大きなマルチシートドメインIと,より小さなアルファヘリカルドメインIIで構成されています.
- ドメインIは,FADを含む酵素と構造的に類似している.
- 配列が保存された領域,特に頂点の領域は,Rab 結合に不可欠です.
結論:
- 決定された構造は,GDIの分子構造と機能の洞察を提供します.
- GDI内の特定の保存領域は,Rabタンパク質との相互作用のために不可欠であり,Rab GTPaseの調節を促進します.
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...
Rab Proteins
Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
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.
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:


