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Updated: Jul 6, 2026

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Induction and Analysis of Epithelial to Mesenchymal Transition
Published on: August 27, 2013
循環型AMPは,CREBをセルリン133でリン酸化することによって,ソマトスタチン遺伝子転写を刺激する
1Clayton Foundation Laboratory for Peptide Biology, Salk Institute, La Jolla, California 92037.
Cell
|November 17, 1989
まとめ
セル-133でのCREBのリン酸化は,cAMP反応性遺伝子転写に不可欠である. この研究では,フォルスコリンは生体内でCREBのリン酸化を誘導し,遺伝子発現を活性化することを示しています.
科学分野:
- 分子生物学は分子生物学である.
- セルラー・シグナリング
- 遺伝子規制 遺伝子規制
背景:
- サイクルAMP (cAMP) は,遺伝子発現を調節する重要な第2メッセンジャーです.
- CREB (cAMP応答要素結合タンパク質) は,cAMPによって活性化される転写因子である.
- CREBのリン酸化を理解することは,cAMP媒介の細胞応答の解読に不可欠です.
研究 の 目的:
- cAMP反応性遺伝子のトランス活性化におけるセル-133におけるCREBリン酸化の役割を調査する.
- CREBのリン酸化と遺伝子転写の間の因果関係を確立する.
- CREBのリン酸化が転写を刺激するメカニズムを解明する.
主な方法:
- フォルスコリンによるPC12細胞およびF9テロカルシノーマ細胞の治療.
- キナーゼA欠乏PC12細胞系 (A126-1B2) を利用する.
- セル-133のリン酸化部位を変更するためのCREBcDNAのインビトロ変異.
主要な成果:
- フォースコリン治療は,生体内でセル-133でCREBのリン酸化を6倍に増加させた.
- キナーゼA欠乏細胞では,CREBのリン酸化誘導は観察されなかった.
- セル-133のリン酸化部位を変異させることで,CREBの転写活動が廃止された.
- セル-133の酸性残留を有するCREB変異体も,転写的に無活性であった.
結論:
- セル-133でCREBのリン酸化は,その転写活動に不可欠である.
- CREBのリン酸化は,cAMP反応性遺伝子の誘導における重要なイベントである.
- CREBのリン酸化による転写刺激のメカニズムには,単なる電荷変化以上のものが含まれている可能性があります.
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