脂質二重層におけるKVAP電圧依存のK+チャネルの分子構造
Luis G Cuello1, D Marien Cortes, Eduardo Perozo
1Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA 22906, USA.
Science (New York, N.Y.)
|October 16, 2004
まとめ
研究者は,プロカリオットの電圧依存のK+チャネル (KvAP) の構造と動態を研究した. 主要な調査結果は,S4セグメントを明らかにしています.
科学分野:
- バイオフィジックス 生物物理学
- 構造生物学 構造生物学とは
- 膜タンパク質 膜タンパク質
背景:
- 電圧依存のカリウムチャネル (Kvチャネル) は,細胞の電気信号伝送に不可欠です.
- 原生膜環境におけるKVチャネルの構造-機能関係を理解することは不可欠です.
研究 の 目的:
- 0mVのプロカリオット電圧依存K+チャネル (KvAP) の局所構造と動態を解明する.
- 膜内のS4およびS1セグメントの位置とダイナミクスを調査する.
主な方法:
- サイト・ディレクテッド・スピン・ラベリング (SDSL) と電子パラマグネティック共振 (EPR) スペクトロスコーピーを組み合わせた.
- 特定のチャンネルセグメントのアクセシビリティとダイナミクスの分析.
主要な成果:
- S4セグメントは,タンパク質/脂質インターフェイスに位置し,荷電は脂質環境から大きく遮断されています.
- S4セグメントは高いダイナミクスを発揮し,柔軟な領域で結びついている2つの短いヘリで構成されています.
- S1セグメントは他のタンパク質成分に囲まれており,電圧感知領域と毛穴領域のインターフェースに位置することを示唆しています.
結論:
- この研究は,生物膜におけるKVAPの構造的組織についての洞察を提供します.
- 結果は,電圧依存のチャネル構造と機能の一般的な原則を確立します.
- 提案されたモデルは,タンパク質ドメインと脂質二重層の相互作用を強調しています.
さらに関連する動画
11:42Reconstitution of a Transmembrane Protein, the Voltage-gated Ion Channel, KvAP, into Giant Unilamellar Vesicles for Microscopy and Patch Clamp Studies
Published on: January 22, 2015
11:19Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
Published on: July 4, 2016
関連する概念動画
01:19Ion Channels
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
01:30ATP Driven Pumps III: V-type Pumps
V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
01:26Voltage-gated Ion Channels
Voltage-gated ion channels are transmembrane proteins that open and close in response to changes in the membrane potential. They are present on the membranes of all electrically excitable cells such as neurons, heart, and muscle cells.
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
01:09Multi-pass Transmembrane Proteins and β-barrels
In multi-pass transmembrane proteins, the polypeptide chain crosses the membrane more than once. The transmembrane polypeptide chain either forms an α-helix or β-strand structure. α-Helix containing multi-pass transmembrane proteins are ubiquitous, whereas β-strand containing ones are mainly found in gram-negative bacteria, mitochondria, and chloroplasts.
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
01:21Electrochemical Gradient and Channel Proteins: An Overview
An electrochemical gradient is a fundamental concept in biology and chemistry. It regulates the movement of ions across cell membranes. This movement is influenced by two factors:
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
01:26Voltage-gated Ion Channels
Voltage-gated ion channels are transmembrane proteins that open and close in response to changes in the membrane potential. They are present on the membranes of all electrically excitable cells such as neurons, heart, and muscle cells.
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...