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C9orf72 ディペプチドリピート 膜のない器官の組立,動力,機能を損なう
Kyung-Ha Lee1, Peipei Zhang1, Hong Joo Kim1
1Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
Cell
|October 22, 2016
まとめ
ALS/FTDにおけるC9ORF72の再発は,細胞のコンパートメントを破壊する有毒なタンパク質を生成します. アルギニンを含むディペプチドリピートタンパク質は,膜のない臓器細胞と相互作用し,その機能を変化させます.
科学分野:
- 神経科学
- 分子生物学
- 遺伝学
背景:
- アミオトロフィック横筋硬化症 (ALS) とフロントテンポラル認知症 (FTD) の最も一般的な遺伝的原因は,C9ORF72遺伝子のヘクサヌクレオチド再発 (GGGGCCまたはG4C2) です.
- この反復拡張は,非従来の翻訳によって毒性ダイペプチド反復 (DPR) タンパク質の生成につながります.
- これらのDPRタンパク質はC9ORF72関連ALSとFTDの病原化に関与しています.
研究 の 目的:
- C9ORF72の繰り返し拡張によって生成されたすべてのDPRのタンパク質インタラクトームを識別する.
- これらの相互作用の機能的結果,特に膜のない器官について調査する.
- DPR が神経変性に寄与するメカニズムを解明する.
主な方法:
- DPRのインタラクタを特定するためのプロテオミック分析
- タンパク質とタンパク質の相互作用と相分離を研究する生化学的測定法
- 細胞と遺伝子モデル (ドロソフィラ) で,確認された相互作用とメカニズムのインビボ関連性を評価する.
主要な成果:
- アルギニンを含むDPRs,特にポリGly-Arg (GR) とポリPro-Arg (PR) は,RNA結合タンパク質と低複雑性配列ドメイン (LCD) のタンパク質と相互作用することが判明した.
- GR/PRインタラクターの有意な部分は,核細胞,核孔複合体,およびストレス粒子を含む,重要な膜のない臓器細胞の構成要素である.
- GRとPRタンパク質は,LCDを含むタンパク質の相分離特性を変化させ,これらの細胞区画の動態と機能を破壊することが示された.
- ドロソフィラの遺伝子研究では,これらの相互作用がDPR媒介の毒性における役割を確認した.
結論:
- DPR,特にGRとPRは,膜のない臓器の成分と相互作用し,その正常な機能を妨害する.
- C9ORF72に関連したALSとFTDで観察された神経毒性には,DPRによる膜のない臓器動態の破壊が寄与する.
- これらの相互作用や 変化した相分離をターゲットにすることで これらの破壊的な神経変性疾患の 治療戦略を提供できます
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