転写因子XBP1による肝臓脂質生成の調節
Ann-Hwee Lee1, Erez F Scapa, David E Cohen
1Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA. ahlee@hsph.harvard.edu
まとめ
転写因子XBP1は,肝臓における脂肪酸合成を調節する. マウスのXBP1を削除すると,コレステロールとトリグリセリドが低下し,脂質代謝におけるXBP1の役割と脂質不全症への潜在的な影響を示唆した.
科学分野:
- 代謝の調節 メタボリックの調節
- 分子生物学は分子生物学である.
- 脂質代謝 脂質代謝とは
背景:
- 食事中の炭水化物は,重要な酵素発現を制御することによって,肝臓の脂肪生成に影響を与えます.
- 展開されたタンパク質応答の調節体であるXBP1は,タンパク質の折り畳みを超えた役割について調査されています.
研究 の 目的:
- 転写因子XBP1が肝臓の脂質生成を調節するかどうかを判断する.
- 脂肪酸合成と肝臓における脂質生成におけるXBP1の役割を調査する.
主な方法:
- マウスモデルを使用して,炭水化物を摂取した後のXBP1タンパク質発現を研究した.
- 肝臓におけるXBP1の誘導性および選択的消去は,その機能を評価するために行われました.
- コレステロール,トリグリセリド,肝臓ステアトーシス,タンパク質分泌機能の測定が行われました.
主要な成果:
- XBP1タンパク質のレベルは,炭水化物を摂取したマウスで増加し,誘発性脂質生成遺伝子と相関しています.
- 肝臓XBP1の選択的消去は,血液中のコレステロールとトリグリセリドの有意な低下につながった.
- 肝臓の脂質の産生が減少したところは,肝臓脂肪酸症を引き起こすことなく,タンパク質の分泌を阻害することなく観察されました.
結論:
- XBP1は肝臓の脂質生成と脂肪酸合成の重要な調節体です.
- XBP1をターゲットにすることで,ヒトの脂質不全症に対する治療戦略を提供することができる.
- XBP1の機能は,展開されたタンパク質応答における役割とは独立して,代謝調節に及ぶ.
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