脳のRNA編集は,グルタミン酸ゲートチャネルにおけるイオンフローの決定因子を制御する
B Sommer1, M Köhler, R Sprengel
1Laboratory for Molecular Neuroendocrinology, University of Heidelberg, Federal Republic of Germany.
Cell
|October 4, 1991
まとめ
RNA編集はグルタミン酸受容体のトランスクリプトを変化させ,イオンチャネル内のアルギニン/グルタミン酸残留物を変化させます. このプロセスは脳内のイオンフローの性質に影響し,受容体タイプによって効率が異なる.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- L-グルタミン酸は,脳の主要な興奮神経伝達物質であり,イオンチャネル経由で急速な神経伝達を調節します.
- グルタミン酸受容体チャネルは,亜単位で構成され,特定の残留物がイオンフロー特性に影響します.
研究 の 目的:
- グルタミン酸受容体チャネルサブユニットで見つかったアルギニン残留物の源を調査する.
- グルタミン酸受容体のトランスクリプトにアルジニンコドンの存在にRNA編集が責任があるかどうかを判断する.
主な方法:
- グルタミン酸受容体チャネルセグメントをコードするゲノムDNA配列の分析.
- ゲノム配列と対応するmRNA配列の比較.
- コドン変異の源として複数の遺伝子と代替エクソンを排除する.
主要な成果:
- ゲノムDNA配列は,特定のチャネルセグメントの位置にグルタミンコドン (CAG) を一貫してコードする.
- 3つのグルタミン酸受容体サブユニットのmRNAトランスクリプトには,同じ位置にあるアルギニンコドン (CGG) が含まれています.
- アルギニンコドンの存在は,複数の遺伝子または代替スプライシングによるものではありません.
結論:
- RNA編集は,グルタミン酸受容体のサブユニットトランスクリプトをアルジニンコドンを含むように変更するメカニズムとして提案されています.
- このRNA編集プロセスは,アルギニン残基を導入することにより,イオンチャネル特性に影響を及ぼします.
- RNA編集の効率性と選択性は,研究されたグルタミン酸受容体サブユニットの2つのクラス間で異なります.
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