シス-ヒドロキシプロリンを含む非螺旋型プロコラーゲンの保持は,粗末なエンドプラズマ網膜に留まります

J Uitto, H Hoffman, D J Prockop

Science (New York, N.Y.)

|December 19, 1975

まとめ

プロリンアナログで治療された線維芽細胞は,非螺旋型のプロコラーゲンを蓄積した. この異常なコラーゲンは,粗なエンドプラズマの網膜に留まり,正常なタンパク質の処理と輸送を妨げました.

科学分野:

バイオケミストリーバイオケミストリー
細胞生物学細胞生物学
分子生物学は分子生物学である.

背景:

コラーゲンは,繊維芽細胞によって合成される重要な構造タンパク質です.
コラーゲンの適切な折り畳みと加工は,その機能に不可欠です.
プロリン水酸化は,コラーゲンの安定性のための重要な翻訳後の修正です.

研究の目的:

プロリンアナログの存在下で合成されたプロコラーゲンの細胞内運命を調査する.
プロリンアナログがコラーゲンの加工と輸送に影響するかどうかを判断する.
エンドプラズマ網膜の機能に対する非螺旋型プロコラーゲンの影響を調べる.

主な方法:

主要な線維芽細胞培養は,胚から確立されました.
細胞は,プロリンアナログであるcis-4-hydroxy-L-prolineでインキュベートされました.
細胞区間のタンパク質の蓄積と局所化を分析した.

主要な成果:

新しく合成されたタンパク質にcis-4-hydroxy-L-prolineを組み込む.
非螺旋型プロコラーゲンの重要な細胞内蓄積.
アナログを含むプロコラーゲンの保持は,粗末なエンドプラズマ網膜内にある.
円滑なエンドプラズマ網膜とゴルギ装置への輸送が遅れたり阻害されたりします.

結論:

プロリンアナログであるcis-4-hydroxy-L-prolineは,正常なプロコラーゲン折り畳みを妨害する.
非螺旋型のプロコラーゲンは,粗末なエンドプラズマ網膜に留まり,チェックポイントメカニズムを示しています.
この保持は,コラーゲンの正常な分泌経路を損なう.

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