ペプチドアンフィフィールナノファイバーの自己組み立てと鉱化
J D Hartgerink1, E Beniash, S I Stupp
1Department of Materials Science and Engineering, Medical School, Northwestern University, 2225 North Campus Drive, Evanston, IL 60208, USA.
まとめ
研究者らは,細胞外マトリックスを模倣するペプチドアンフィフィール・ナノファイバー・スカファードを作成した. このバイオマテリアルは,その整合性を制御するためにクロスリンクされ,骨のような複合材料のためのヒドロキシアパタイト鉱化を直接することができます.
科学分野:
- バイオマテリアル科学 バイオマテリアル科学
- ナノテクノロジー ナノテクノロジー
- バイオミネラライゼーション
背景:
- 細胞外マトリックス (ECM) は,組織機能に不可欠な構造的サポートと生化学的シグナルを提供します.
- ECMのナノ構造を模倣することは,組織工学と再生医療のための高度な生体材料の開発に不可欠です.
- ペプチドの自己組み立てを制御して秩序あるナノ構造を作ることは,ECMにインスパイアされた支架への有望な経路を提供します.
研究 の 目的:
- 自己組み立てナノファイバーを形成できるペプチド-アンフィフィール系を開発する.
- 逆転可能なクロスリンクメカニズムを設計して,脚本の構造的整合性を調節する.
- これらのナノファイバーが,ヒドロキシアパタイトの鉱化を秩序ある方法で誘導する能力を調査する.
主な方法:
- ナノファイバーを形成するために設計されたペプチドアンフィフィルのpH誘発の自己組み立てを利用しました.
- ナノファイバー・スカファードの機械的性質を変更するための可逆的なクロスリンク戦略を実装しました.
- ハイドロキシアパタイトの前駆物質を用いた in vitro 鉱化実験を行いました.
主要な成果:
- ペプチド-アンフィフィールセルフアセンブリによるナノ構造の繊維構造を成功裏に形成した.
- クロスリンクを通じて,脚架の構造的整合性に対する可逆的な制御が実証されています.
- 水酸化アパタイトの指向された鉱化が達成され,結晶学的なc軸は繊維軸に並べられています.
結論:
- ペプチド-アンフィフィール自己組み立ては,ECM模倣の脚本を作るための多用途のプラットフォームを提供します.
- リバーシブルクロスリンクは,バイオマテリアルアプリケーションに合わせて調整可能な機械的性質を提供します.
- この研究で達成された並べられたヒドロキシアパタイト鉱化は,骨構造を模倣し,骨組織工学の可能性を示唆しています.
関連する概念動画
Assembly of Cytoskeletal Filaments
Cytoskeletal filaments are polymeric forms of smaller protein subunits. However, individual cytoskeletal filaments may easily disassemble or associate with other similar filaments to form rigid structures. Microfilaments, made of actin monomers, rely on actin-binding proteins to form bundles and create networks of individual actin filaments. Microtubules rely on microtubule-associated proteins (MAPs) to form sturdy cylindrical structures. However, the proteins involved in forming complex...
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...
Formation of Higher-order Actin Filaments
The polymerization of G-actin monomers into filamentous F-actin is a multi-step process. Once the F-actins are formed, they can bundle together in different arrangements to form higher-order networks and regulate cellular functions. Common examples include the formation of lamellipodia and filopodia at the cell's leading edge by actin reorganization in a migrating cell. The microvilli on the brush border epithelial cells are also formed through the F-actin network.
The high-order actin networks...
The high-order actin networks...
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.
Mechanism of Filopodia Formation
Filopodia are thin, actin-rich cellular protrusions that play an important role in many fundamental cellular functions. They vary in their occurrence, length, and positioning in different cell types, suggesting their diverse roles.
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
Mechanism of Lamellipodia Formation
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...


