S. pombe の遺伝子 sds22+ は,ミトーシスの中間の移行に不可欠なもので,タンパク質フォスファタゼ-1を正に調節するレウシンに富んだリピートタンパク質をコードする
1Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Cell
|January 11, 1991
まとめ
新しい遺伝子であるsds22+は,分裂酵母における細胞分裂サイクル,特にメタフェーズからアナフェーズへの移行に不可欠です. タンパク質フォスファタゼ1 (PP1) の活性を増強しますが,PP1濃度が高い場合,必要ありません.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- 分裂酵母には2種類の1型タンパク質ファスファタゼ (PP1) がある.
- dis2+遺伝子は1つのPP1をコードし,その変異体dis2-11はミトーシスに欠陥がある.
- ミトーシスには,タンパク質の脱リン酸化の正確な調節が必要です.
研究 の 目的:
- dis2-11変異を補完する高用量抑制剤であるsds22+を特徴づける.
- ミトーシスにおけるsds22+の機能とPP1との関係を研究する.
- sds22+タンパク質の構造的および機能的性質を決定する.
主な方法:
- 遺伝子クローニングとsds22+の配列決定
- 遺伝子破壊と高用量補充を含む遺伝分析.
- タンパク質の局所を決定するための生化学的分化.
- 野生型および変異株における細胞サイクル進行の分析.
主要な成果:
- sds22+は,溶解不可能な核分数に局所化された,レウシンリピートに富んだ新しい30kDのタンパク質をコードします.
- sds22+は,メタフェーズ/アナフェーズ移行に不可欠であり,その中断はミトーシス停止を引き起こす.
- PP1遺伝子の高用量は,sds22+ヌルフェノタイプを抑制し,機能的相互作用を示しています.
- sds22+製品はPP1に依存した脱リン酸化を強化しますが,PP1の機能を置き換えることはありません.
結論:
- sds22+は,分裂酵母におけるミトス進行に必要な不可欠な遺伝子である.
- sds22+タンパク質はPP1の調節サブユニットまたはコファクターとして作用し,PP1の活性を増強する可能性がある.
- sds22+は,ミトーシス中期における重要なPP1依存型脱酸化を促します.
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