エンドキュトーシス. 内細胞部位は,クラトリン層の絶え間ない屈折と再構成によって成熟する
Ori Avinoam1, Martin Schorb2, Carsten J Beese3
1Cell Biology and Biophysics Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. Structural and Computational Biology Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany.
まとめ
クラスリン媒介性内分細胞症は,クラスリンコートの動的屈曲を伴うもので,最初の平らな膜組立ではない. このプロセスは,事前に組み立てられたクラトリンの構造を再構成することによって,膀の芽生えを容易にします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学と細胞生物学について
- バイオフィジックス 生物物理学
背景:
- クラトリン媒介内分細胞症 (CME) は,分子回収のために,血膜領域を内化します.
- CMEにおける重要な議論は,クラトリンの組成が曲線か平らな膜で起こるかどうかである.
研究 の 目的:
- エンドサイトーシス中のクラトリンコート組成と膀形成のメカニズムを調査する.
- 曲線膜のクラトリンの直接組成モデルと,その後の再構成による平面膜への採用モデルを区別する.
主な方法:
- 先進的な光顕微鏡と電子トモグラフィを組み合わせた.
- 内細胞部位を視覚化し,陰性期中のクラトリンコートと膜の形状を分析した.
主要な成果:
- 膀の芽生えの間に,ほぼ恒常的なコーティングされた表面積でクラトリンコートの曲線が増加することが観察されました.
- クラスリン媒介性エンドサイトーシスプロセスのすべての段階において,迅速なクラスリン交換が実証されています.
結論:
- CMEにおけるコーティングされた膀の芽生えは,事前に組み立てられたダイナミックなクラスリンコートの曲げによって引き起こされます.
- この発見は,クラスリン層が,平らな膜にデノボで組み立てられるのではなく,積極的に再構成されるモデルを支持する.
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