関連する実験動画
Updated: Jun 21, 2026

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DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers
Published on: October 25, 2017
螺旋型のナノフィラメントフェーズ
まとめ
アキラル分子は,ナノスケールフィラメントの内部で,歪んだホモキラル層に自己組織化します. このユニークな構造は,マクロスコプ的一貫性を持つ液晶相を形成し,新しいキラル順序を明らかにします.
科学分野:
- 材料科学 材料科学とは
- クリスタログラフィーです.
- ソフトマター物理学 ソフトマター物理学
背景:
- チラルの結晶形成は,典型的には分子チラリティを含みますが,歪みはしばしばストレスのために格子から排出されます.
- アキラル分子は通常,アキラル構造を形成し,固有の手性がない.
研究 の 目的:
- キラル性質を示すアキラル分子から形成された物質の秩序ある状態を調査する.
- 空間的拘束が分子秩序と対称性の破綻にどのように影響するかを理解する.
主な方法:
- ナノスケールフィラメントにアキラル分子の自己組み立て.
- フィラメント内の層次的な組織の構造分析.
- マクロスコーピック液晶相の特徴.
主要な成果:
- アキラル分子が自己組織化して,周期的に秩序づけられたナノスケールフィラメントを形成する.
- これらのフィラメントの内部の層は,重要な歪みと厳格なホモキラリティ,すなわち,折れた対称性の形態を示した.
- フィラメントの集合的組織は,回転のマクロスコプ的一貫性をもたらし,液晶相を形成しました.
結論:
- フィラメントに空間的に閉じ込められることで,アキラルな分子がキラルな構造を形成できます.
- この自己組み立てプロセスは,トウィストと格子順序の不一致を克服します.
- その結果生じる液晶相は,マクロスコーピカルキラル組織のための新しいメカニズムを示しています.
関連する概念動画
Formation of Intermediate Filaments
Intermediate filaments are cytoskeletal proteins with higher tensile strength and flexibility than microfilaments and microtubules. Unlike the other two cytoskeletal proteins, intermediate filament formation lacks the enzymatic activity to hydrolyze nucleotides like ATP and GTP to generate energy for polymerization. Therefore, the formation of intermediate filaments is multistep self-assembly. The involvement of any accessory proteins in intermediate filament formation has not yet been reported.
Generation of Straight or Branched Actin Filaments
The straight or branched structure formation of actin filaments is controlled by nucleating proteins such as the formins and Arp2/3 complex. Formin-mediated assembly results in straight filaments, whereas Arp2/3 protein complex-mediated assembly results in branched actin filaments.
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
Arp2/3 Complex
Arp2/3 complex is a seven-subunit complex consisting of two proteins similar to actin- Arp2 and Arp3, and five other subunits that help keep Arp2 and Arp3 inactive. When required, the complex is...
The Structure of Intermediate Filaments
The intermediate filaments are one of three widely studied cytoskeletal filaments. They are so named as their diameter (10 nm) is in between that of microfilaments (7 nm) and the microtubules (25 nm). These filaments are highly stable and can remain intact when exposed to high salt concentrations and detergents. These filaments are responsible for providing stability and mechanical support to the cells. They also help in cell adhesion and maintaining tissue integrity.
Intermediate filaments...
Intermediate filaments...
Actin Polymerization
Actin polymerization occurs through the head-to-tail association of binding sites on monomeric actin or G-actin to form filamentous or F-actin. The polymerization can be divided into three phases ̶ nucleation, elongation, and steady-state phase.
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
The nucleation phase involves forming a stable nucleus consisting of three actin monomers to form a new actin filament. Actin-binding proteins such as formins and Arp2/3 complex help filament growth post-nucleation. The Formins form straight actin...
Types of Intermediate Filaments
The intermediate filaments are an essential component of the cytoskeleton. Presently six types of intermediate filament have been identified. Type I and II are acidic and basic keratin proteins. Type III is of mesodermal origin and comprises four proteins: vimentin, desmin, glial fibrillary acidic protein (GFAP), and peripherin. Vimentin is commonly found in mesenchymal cells, desmin in muscle cells, GFAP in astrocytes, while peripherin is found in peripheral nervous system neurons (PNS). Type...
Disassembly of Intermediate Filaments
Intermediate filaments (IFs) do not undergo spontaneous disassembly. Enzymes, kinases, and phosphatases add and remove phosphates from specific sites to regulate their disassembly. The IF concentration in the cytoplasm also regulates the disassembly. If the concentration crosses a threshold, it activates the protein kinases in the vicinity, allowing the phosphorylation of IFs.
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...
Keratin proteins, found at the cell periphery near cell junctions, undergo a cycle of assembly and disassembly. In Type...

