リモートサイトリン酸化による内在的に乱れた脚架タンパク質,LATへのGrb2のアロステリック変調
William Y C Huang1,2, Jonathon A Ditlev1,3, Han-Kuei Chiang2
1The Howard Hughes Medical Institute Summer Institute, Marine Biological Laboratory , Woods Hole, Massachusetts 02543, United States.
Journal of the American Chemical Society
|November 29, 2017
まとめ
T細胞受容体 (TCR) のシグナル伝達において重要な役割を果たすLATタンパク質の多価リン酸化は,Grb2結合を調節するアロステリックメカニズムを明らかにする. この複雑なプロセスは信号伝送を妨げ,効率的なT細胞活性化には複数のリン酸化イベントが必要です.
科学分野:
- セルラー信号
- 分子生物学
- 免疫学
背景:
- 細胞内信号伝導は,受容体と支架タンパク質のチロシンリン酸化に依存する.
- T細胞活性化 (LAT) のリンカーとGrb2募集は,T細胞受容体 (TCR) の初期活性化において極めて重要です.
- LATの複数のリン酸化部位は複雑な調節作用を示唆している.
研究 の 目的:
- LATの多価リン酸化がTCRシグナル伝達に与える影響を定量的に分析する.
- LAT:Grb2の相互作用を制御するアロステリックメカニズムを解明する.
- 膜の局所化がLAT:Grb2結合と信号伝送にどのように影響するかを理解する.
主な方法:
- 支持膜のTCR信号経路の初期反応を再構成する.
- 結合型チロシン残留変異によるLAT構造の分析
- Grb2をレポーターとして使用し,ZAP-70キナーゼを用いてLATリン酸化をモニターする.
主要な成果:
- リモートチロシンリン酸化がLAT:Grb2結合親和に影響する新しいアロステリックメカニズムを発見した.
- LAT:Grb2結合は膜局所によって調節され,主に運動オンレートに影響する.
- 膜のZAP-70によるLATのリン酸化は,弱いプロセス性触媒を示している.
結論:
- LATの多価リン酸化はゲートとして作用し,効率的な信号伝送には複数のイベントが必要です.
- リン酸化はLATの構造を変化させ,Grb2のアクセシビリティを調節する.
- このアロステリック調節はT細胞における信号伝播の制御に不可欠である.
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