CREBは,コアクティベーターPGC-1を通じて肝臓のグルコネオゲネシスを調節する
1Peptide Biology Laboratories, Salk Institute for Biological Studies, 10010 N Torrey Pines Road, La Jolla, California 92037-1002, USA.
Nature
|September 15, 2001
まとめ
循環型AMP (cAMP) 応答要素結合 (CREB) タンパク質は,グルコン生成の重要な要因であるPGC-1を活性化することによって,断食中のグルコースホメオスタシスを調節する. この経路は,断食中の低血糖症の予防に不可欠であり,II型糖尿病に関与している可能性があります.
科学分野:
- メタボリック調節 メタボリック調節
- 分子内分泌学は分子内分泌学である.
- 遺伝子発現 遺伝子発現 遺伝子発現 遺伝子発現
背景:
- 哺乳類の断食は,グルカゴンとグルココルチコイドを介してグルコネオゲネシスを引き起こす.
- 糖質合成のシナギスティック誘導のための正確な分子機構は不明である.
- これらの経路を理解することは,代謝疾患の研究に不可欠です.
研究 の 目的:
- CREBがグルコン生成を調節するメカニズムを解明する.
- CREB媒介のグルコースホメオスタシスにおけるPGC-1の役割を特定する.
- CREB,PGC-1,および肝臓のグルコン生成の関連性を調査する.
主な方法:
- マウスでの遺伝子破壊と過剰発現の研究.
- グルコネオゲン遺伝子発現の分析.
- In vivo CREB 調節アッセイについて.
- PGC-1の機能を評価するためのトランジントトランスフェクションアッセイ.
主要な成果:
- CREBの欠乏または抑制は,断食中の低血糖症とグルコネオゲン酵素発現の低下につながる.
- CREBは,PGC-1の発現をin vivoで直接調節する.
- CREB欠乏したマウスのPGC-1過剰発現は,グルコースホメオスタシスを回復させた.
- PGC-1は,重要なグルコネオゲン酵素であるPEPCKのグルココルチコイド誘導を強化します.
結論:
- CREBは,PGC-1を直接調節することによって,グルコネオゲン系プログラムを活性化します.
- PGC-1は肝臓のグルコネオゲネシスのためのcAMPとグルココルチコイドシグナリングを統合する重要な共同活性化剤として作用します.
- 肝臓におけるCREB-PGC-1経路の調節障害は,II型糖尿病の病原化に寄与する可能性があります.
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