GRASPに依存する非従来の分泌経路を通じて ΔF508-CFTR の密輸を救済する
Heon Yung Gee1, Shin Hye Noh, Bor Luen Tang
1Department of Pharmacology, Brain Korea 21 Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 120-752, Korea.
Cell
|September 3, 2011
まとめ
胞性線維症変異の ΔF508-CFTR 表面表現は,従来とは異なる GRASP 依存経路によって回復されます. このアプローチは,マウスのCFTR機能と生存を救出し,潜在的な治療戦略を提供します.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 生理学 生理学とは
背景:
- 性線維症の主要な変異であるPhe508デリエーション (ΔF508) は,CFTRタンパク質の密輸と細胞表面発現を損なう.
- 従来のタンパク質分泌経路では,ΔF508-CFTRを細胞表面に適切に輸送することができません.
研究 の 目的:
- ΔF508-CFTRの表面表現を救出するための非常識な分泌経路を調査する.
- CFTR機能不全を修正するGRASP依存分泌の役割を調査する.
主な方法:
- CFTRの密輸を研究するために,分子および生理学的分析を用いた.
- ストレス誘発のER経路とGRASP媒介の分泌を調査した.
- フォスフォリレーションとタンパク質の相互作用を調査し,密輸に不可欠である.
- GRASP.発現するトランスジェニック ΔF508-CFTR マウスを生成した.
主要な成果:
- ΔF508-CFTRの表面発現は,GRASPに依存した経路を介して,in vitroおよびin vivoで救出されました.
- ERのストレスメカニズムは,この非常識な経路を通じて,野生型と ΔF508-CFTR の密輸を促進します.
- GRASPのリン酸化と,CFTRとのPDZベースの相互作用は,この救済に不可欠です.
- マウスのトランスジェニックGRASP発現はCFTR機能を回復させ,毒性のない生存率を向上させた.
結論:
- 非伝統的なGRASP依存分泌は,ΔF508-CFTRの欠陥を修正するための実行可能な戦略を提供します.
- この経路は,ERストレス媒介によるタンパク質の密輸に関する洞察を提供します.
- GRASPをターゲットにすることは,システィック線維症やその他のタンパク質の誤折り疾患に対する潜在的な治療の道を示しています.
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