C9orf72 GGGGCCのリピートは,FTLD/ALSにおける二ペプチドリピートタンパク質の集積に変換される
Kohji Mori1, Shih-Ming Weng, Thomas Arzberger
1Adolf Butenandt-Institute, Biochemistry, Ludwig-Maximilians University (LMU) Munich, Munich, Germany.
まとめ
ファミリアルフロントテンポラルロバー変性およびALSの最も一般的な遺伝的原因であるC9orf72ヘクサヌクレオチドの繰り返し膨張は,特定のタンパク質の含有につながります. これらのインクルージョンにはディペプチドリピートタンパク質が含まれており,遺伝子変異を観察された病理学と直接関連付けています.
科学分野:
- 神経科学は神経科学である.
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
背景:
- ファミリアル前頭側頭葉変性およびアミオトロフィック横筋硬化症 (FTLD/ALS) は,しばしばC9orf72ヘクサヌクレオチドの繰り返し膨張によって引き起こされます.
- C9orf72に関連した病理学の基礎となる病理メカニズムとタンパク質インクルージョンの組成は,依然としてほとんど不明です.
研究 の 目的:
- C9orf72病理学で見られる特徴的な細胞内インクルージョン内のコアタンパク質を特定する.
- C9orf72遺伝子の変異と観察された病理的なタンパク質集積物との間の直接的なリンクを確立する.
主な方法:
- C9orf72ヘクサヌクレオチドの繰り返し膨張による患者サンプルにおける細胞内インクルージョンの分析.
- プロテオミックおよび生化学的技術を用いて,これらのインクルージョン内のタンパク質成分を特定する.
主要な成果:
- 特徴的なインクルージョンのほとんどは,ポリ- ((Gly-Ala) ディペプチドリピートタンパク質を含んでいる.
- また,より少量のポリ- ((Gly-Pro) とポリ- ((Gly-Arg) ディペプチド・リピートタンパク質も特定されました.
- これらの二ペプチド重複タンパク質は,拡張されたGGGGCC重複の非ATGが開始した翻訳から生じると考えられています.
結論:
- この研究では,特定のダイペプチド重複タンパク質が,C9orf72に関連したFTLD/ALS.のインクルージョンの主な成分として特定されています.
- この発見は,C9orf72遺伝子の変異と患者で観察された主要な病理学的特徴との間の直接的な分子関連性を示しています.
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