β細胞のインスリン分泌には,ウビキチンリガゼCOP1が必要です
Rowena Suriben1, Kelly A Kaihara2, Magdalena Paolino1
1Department of Physiological Chemistry, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA.
Cell
|December 3, 2015
まとめ
ウビキチンリガゼCOP1は,胰腺ベータ細胞のETV転写因子を調節し,インスリン分泌と糖尿病の予防に不可欠です. これらの因子を消去すると 糖尿病を救うことが可能になり 血糖の恒常性における その役割が明らかになるのです
科学分野:
- 内分泌学
- 分子生物学
- 細胞生物学
背景:
- 臓のベータ細胞はインスリンを分泌し,血糖の恒常性を維持する.
- インスリン分泌の調節不良は,糖尿病に寄与する.
- 翻訳後の変化は 細胞の重要なプロセスを制御します
研究 の 目的:
- パンクレアベータ細胞におけるETV転写因子のCOP1媒介後の調節の役割を調査する.
- この規則がインスリン分泌とグルコースホメオスタシスに与える影響を決定する.
主な方法:
- ベータ細胞のCOP1を欠いたマウスを生成した.
- Etv1,Etv4,Etv5の遺伝子削除を行った.
- インスリン分泌と粒子のドッキングを分析した.
- 遺伝子発現パターンを調べました
主要な成果:
- ベータ細胞のCOP1の喪失は,インスリン粒子のドッキング障害による糖尿病を引き起こした.
- Etv1,Etv4,Etv5の遺伝的削除により 糖尿病の表型が救われました
- COP1欠乏細胞のETVによって調節される遺伝子は,ヒトの糖尿病に関連した遺伝子で濃縮された.
- ETV4は脱極化と高血糖期におけるインスリン分泌の制限により安定した.
結論:
- COP1によるETV転写因子の調節は,インスリン分泌と正常血糖の維持に不可欠である.
- ETVは,特に高血糖状態では,インスリン分泌の負の調節剤として作用する.
- これらの発見は,ヒトベータ細胞病理学と糖尿病におけるETVの役割が保存されていることを示唆している.
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