KAR3は,酵母核融合に必要なキネシン関連遺伝子です

P B Meluh¹, M D Rose

¹Department of Biology, Lewis Thomas Laboratory, Princeton University, New Jersey 08544-1014.

Cell

|March 23, 1990

まとめ

KAR3遺伝子は酵母核融合に不可欠であり,キネシンのようなタンパク質として作用します. 変異は,このプロセスを妨害し,KAR3を強調します.

科学分野:

細胞生物学細胞生物学
分子遺伝学分子遺伝学
バイオケミストリーバイオケミストリー

背景:

KAR3遺伝子は,交配中の酵母核融合に重要な役割を果たしています.
KAR3の発現は,重要な交配フェロモンであるアルファ因子によって著しく上調されます.

研究の目的:

酵母核融合におけるKAR3タンパク質の機能とメカニズムを調査する.
KAR3の構造領域と,マイクロチューブル結合と運動活動におけるその役割の特徴を明らかにする.

主な方法:

機能ドメインを特定するために,KAR3タンパク質の配列分析.
機能におけるその役割を評価するために,推定ATP結合部位のサイト指向型変異.
ハイブリッド構造を含む,野生型および突然変異のKAR3タンパク質のインビボ局所化研究.

主要な成果:

KAR3タンパク質は,2つの球状ドメインと,アルファヘリル状のコイル状のコイルを持ち,キネシン重鎖の同型である.
ATP結合部位における突然変異は,核融合に多大な悪影響を及ぼし,マイクロチューブルの結合が強化された.
KAR3のアミノ端末ドメインは,サイトプラズマ微小管との結合を媒介する.

結論:

KAR3は,マイクロチューブルベースのプロセスに関与するキネシンのようなタンパク質です.
このタンパク質は,核融合および潜在的にミトーシス中のマイクロチューブルスライディングを媒介することによって機能する可能性があります.
KAR3は,様々なタンパク質結合ドメインを持つキネシンのようなタンパク質の家族を表しています.

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