Ser-Thrキナーゼにおけるアロステル活性化の古代起源
Adelajda Hadzipasic1,2, Christopher Wilson1,2, Vy Nguyen1,2
1Department of Biochemistry, Brandeis University, Waltham, MA 02454, USA.
まとめ
オーロラAキナーゼとその活性化剤TPX2 (Xklp2を標的とするタンパク質) のアロステリック調節の進化を研究した. 古代のオートフォスフォリレーションメカニズムは安定したままで,TPX2媒介による調節はキナーゼ自体の中で進化した.
科学分野:
- 生物化学
- 進化生物学
- 分子生物学
背景:
- アロステリック調節は多数の細胞プロセスに不可欠です.
- アロステリーの進化を理解することで 生物学的メカニズムに関する 根本的な洞察が得られます
研究 の 目的:
- オーロラAキナーゼとTPX2間のアロステル活性化の進化軌道を再構築し,実験的に分析する.
- キナーゼ調節の古代起源とその後の発展を調査する.
主な方法:
- 祖先の配列を再構築して 祖先のタンパク質を再生する
- 復活した祖先のキナーゼとアクティベータの実験的な特徴付け
- タンパク質とタンパク質の相互作用と規制メカニズムの分析
主要な成果:
- 最も古い活性化メカニズムである活性化ループの自己リン酸化は,古くから存在し,高度に保存されている (>10億年).
- オーロラAキナーゼとマイクロチューブル関連タンパク質TPX2の間の効率的な結合はTPX2の出現後に進化した.
- TPX2媒介によるキナーゼのアロステリック調節は,主に共進化によってではなく,キナーゼの内部にある遺伝的基礎によって徐々に進化した.
結論:
- アロステリック・レギュレーションは 古代のルーツを持ち 核心的なメカニズムが保存されています
- TPX2によるオーロラAキナーゼのような特定のアロステル調節の進化は,調節されたタンパク質そのものにコード化され得る.
- この研究は,アロステル調節のための新しい進化の経路を明らかにし,キナーゼの適応の固有の能力を強調しています.
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