动聚合物的伪原子模型识别了一种依赖于水解的动力冲击
Joshua S Chappie1, Jason A Mears, Shunming Fang
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA.
Cell
|October 4, 2011
概括
对dynamin 1的结构洞察力揭示了G域二次体在四次体内如何驱动膜裂变. 这个GTPasease.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 动氨酸是一种GTPase,对膜裂变至关重要,特别是在氨酸涂层坑裂变中.
- 精确的结构机制和构造变化,底层的动力素的功能仍然不完全理解.
研究的目的:
- 为了阐明激素1的膜裂变活动的结构基础.
- 描述胺聚合物内部的相互作用和构造变化.
主要方法:
- 采用X射线晶体学,确定了一个截断的人类动1螺旋聚合物和一个G域-GED融合蛋白的结构.
- 化学交叉连接被用来研究动氨酸四聚合物组成和分子间相互作用.
主要成果:
- 该研究介绍了dynamin 1组件的高分辨率结构,详细说明了G域二次体在四次体内和跨聚合物层中的排列.
- 动氨酸四分体由两个二分体组成,其中一个分子的G域与另一个分子的GTPase效应域 (GED) 相互作用.
- 通过结构比较确定了一种依赖于水解的动力冲击机制,这表明它在膜重塑中的作用.
结论:
- 这些发现澄清了动胺聚合物的结构组织以及驱动膜裂变的特定分子相互作用.
- 鉴定到的动力冲击机制为动在囊泡发芽和分裂过程中产生力的能力提供了潜在的解释.
相关概念视频
The Movement of Organelles and Vesicles
In eukaryotic cells, cytoskeletal filaments such as actin, microtubules, and intermediate filaments form a mesh-like cytoskeletal network. These filaments serve as tracks for transporting cellular cargo. Specialized motor proteins use the chemical energy stored in adenosine triphosphate (ATP) for this transport. During interphase, microtubules are polarized, with the plus-end towards the cell periphery and the minus-end towards the cell center. Two microtubule-associated motor proteins,...
ATP Synthase: Structure
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
ATP Synthase: Mechanism
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
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...
ATP Driven Pumps II: P-type Pumps
The P-type pumps are a large family of integral membrane transporter ATPases. They are divided into five major types based on substrate specificity, from I to V.
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
ATP Driven Pumps I: An Overview
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...

