膜分裂および融合タンパク質の相互制御
Christopher Peters1, Tonie L Baars, Susanne Bühler
1Département de Biochimie, Université de Lausanne, Chemin des Boveresses 155, 1066 Epalinges, Switzerland. christopher.peters@unil.ch
Cell
|November 20, 2004
まとめ
イーストの真空融合には,GTPase Vps1pが関与し,t-SNAREsをポリメリ化しカップル化する. Sec18p/NSFはVps1pを脱ポリマー化し,核融合を開始し,無駄な核分裂-核融合サイクルを防ぐ.
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.
- メンブラン取引 メンブラン取引
背景:
- 膜融合と分裂は,細胞過程の反対である.
- ダイナミンは,GTPに依存するメカニズムを通じて膜分裂を媒介する.
- SNAREsは,膀間の複合体を形成することによって,膜融合を媒介する.
研究 の 目的:
- イーストの真空分子融合におけるダイナミンのようなGTPase Vps1pの役割を調査する.
- 膜融合中のVps1pの調節メカニズムを解明する.
主な方法:
- 酵母遺伝学と細胞生物学技術について.
- タンパク質のポリメリゼーションとデポリメリゼーションの分析.
- Vps1p,SNARE,および関連するタンパク質の相互作用を研究する.
主要な成果:
- Vps1pは酵母真空の上で複数のt-SNAREを複合し,結合する.
- Sec18p/NSFは,SNAREを活性化するATPアゼであり,Vps1pをデポリメリ化する.
- Vps1pの放出はSec17p/alpha-SNAPとv-SNAREから独立している.
- Vps1pの放出により,t-SNAREの核融合機能が起動し,核分裂が抑制される.
結論:
- Vps1pは酵母バキュオール融合の調節剤として作用する.
- 核融合 (SNAREs) と核分裂 (Vps1p) 機械の相互制御により,無駄なサイクルが防止されます.
- このメカニズムは,効率的で一方的な膜融合を保証します.
関連する概念動画
Membrane Fluidity
179.8K
Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.
179.8K
Membrane Fluidity
18.2K
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
18.2K
Mechanisms of Membrane-bending
3.7K
The living membranes are flexible due to their fluid mosaic nature; however, their bending into different shapes is an active process regulated by specific lipids and proteins. The membrane bending can be transient as seen in vesicles or stable for a long time as in microvilli. Cells regulate the size, location, and duration of the membrane curvature.
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
3.7K
Fusion of Secretory Vesicles with the Plasma Membrane
19.9K
Proteins and neurotransmitters in secretory vesicles can be released from a cell upon vesicle docking, priming, and fusion with the plasma membrane. Vesicles are docked and primed in preparation for the quick exocytosis of their contents in response to a stimulus. The fusion process is mainly carried out by a SNAP Receptor or SNARE complex, consisting of synaptobrevin, syntaxin-1, and SNAP-25.
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
19.9K
SNAREs and Membrane Fusion
14.0K
Once a transport vesicle has recognized its target organelle, the vesicular membrane needs to fuse with the target membrane to unload the cargo. Transmembrane proteins called SNAREs present on organelle membranes and their vesicles, mediate vesicle fusion.
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
14.0K
Mechanisms of Membrane Domain Formation
4.4K
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with...
Another mechanism for membrane domain formation involves membrane proteins interacting with...
4.4K


