ミニチュアタンパク質は,最小のカチオンのPPIIモチーフを基に,内在的に細胞に浸透します
Douglas S Daniels1, Alanna Schepartz
1Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|November 7, 2007
まとめ
研究者は,ユニークなポリプロリンII (PPII) 螺旋構造を持つ新しい細胞浸透ペプチド (CPPs) を開発しました. これらのCPPは,優れた細胞吸収効率と低細胞毒性を実証し,分子配送技術の有望な進歩を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- バイオテクノロジー バイオテクノロジー
背景:
- 細胞に浸透するペプチド (CPP) は,様々な分子積荷を細胞に運ぶために不可欠です.
- 既存のCPPは,通常非構造的またはアルファヘリカルなカチオンまたはアンフィパティック構造に依存しています.
- 効率と安全性のプロファイルが向上した新しいCPPが必要である.
研究 の 目的:
- タイプIIポリプロリン (PPII) 螺旋構造に基づいた新しい細胞浸透モチーフの設計と特徴付け.
- これらの新しいCPPsの細胞吸収効率と細胞毒性を評価する.
- PPIIヘリが細胞に内在する透過性を与える可能性を評価する.
主な方法:
- PPIIの螺旋構造を組み込んだエンコード可能なCPPの設計.
- 様々な分子負荷を用いた細胞の吸収効率の評価.
- 細胞毒性測定は,高濃度での安全性プロフィールを決定する.
主要な成果:
- 設計されたPPIIベースのCPPは,既存のCPPと比較して,より高い吸収効率を示しました.
- これらの新しいCPPは,投与に必要な濃度より100倍も高い濃度でも,有意な細胞毒性を示しませんでした.
- PPIIヘリクスをミニチュアタンパク質に組み込むことで,サイズを増やさずに細胞の透過性を成功させました.
結論:
- タイプIIポリプロリン (PPII) 螺旋構造は,細胞に浸透するペプチドの新しく効果的なモチーフを表しています.
- これらのPPIIベースのCPPは,細胞内伝達のための安全で高度に効率的なプラットフォームを提供します.
- この研究は,CPPのバイオテクノロジーおよび治療アプリケーションのツールキットを拡張します.
関連する概念動画
Multi-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...
Structure of Porins
Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel precursors...
Single-pass Transmembrane Proteins
Integral membrane proteins are tightly associated with the cell membrane and play a crucial role in cell communication, signaling, adhesion, and transport of the molecules. Some integral membrane proteins are present only in the membrane monolayer. For example, the enzyme fatty acid amide hydrolase is present in the cytoplasmic side of the membrane monolayer. In contrast, another type of integral membrane protein, also known as a transmembrane protein, spans across the membrane. Transmembrane...
Aquaporins
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
Membrane Proteins
Plasma membranes have integral transmembrane proteins involved in facilitated transport. These proteins are collectively referred to as transport proteins, and they function as either channels for the material or as carriers themselves. Channel proteins have hydrophilic domains exposed to the intracellular and extracellular fluids and a hydrophilic channel through their core that provides a hydrated opening for solutes to pass through the membrane layers. Passage through the channel allows...
Introduction to Membrane Proteins
The cell membrane, or plasma membrane, is an ever-changing landscape. It is described as a fluid mosaic where various macromolecules are embedded in the phospholipid bilayer. Among the macromolecules are proteins. The protein content varies across cell types. For example, mitochondrial inner membranes contain ~76% protein content, while myelin contains ~18% protein content. Individual cells contain many types of membrane proteins—red blood cells contain over 50—and different cell types have...


