p21が欠けている細胞における抗がん剤によって誘発されたS相とミトーシスの解離
T Waldman1, C Lengauer, K W Kinzler
1The Howard Hughes Medical Institute, Johns Hopkins Oncology Center, and Program in Human Genetics, Baltimore, Maryland 21231, USA.
Nature
|June 20, 1996
まとめ
タンパク質p21WAF1/CIP1は,ヒト細胞の細胞サイクル相の調整に不可欠です. それなしでは,DNAに損傷した細胞は異常な細胞分裂を経験し,ポリプロイジアとアポトーシスを引き起こします.
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:
- 細胞分裂とストレス誘発による成長停止には,真核細胞周期のS (DNA合成) とM (ミトーシス) 段階の正確な調整が不可欠である.
- 細胞のチェックポイントは,適切な細胞サイクル進行を保証し,ミトーシスブロック後の追加のS相のようなエラーを防止しますが,哺乳類の細胞のメカニズムは完全に理解されていません.
研究 の 目的:
- 人間の細胞におけるSとM相の調整におけるp21WAF1/CIP1の役割を調査する.
- DNA損傷のストレス下における細胞サイクル調整の基礎となる分子機構を解明する.
主な方法:
- 細胞サイクル進行を研究するためにヒトの細胞系を利用した.
- DNA損傷への反応としてp21WAF1/CIP1の機能を調査した.
- p21WAF1/CIP1.1.が欠けている細胞の核形態とDNA含有量を観察した.
主要な成果:
- p21WAF1/CIP1が存在しない場合,DNAに損傷したヒト細胞はG2のような状態で停止するが,正常なミトーシスなしに追加のS段階を経る.
- p21WAF1/CIP1が欠けている細胞は,変形した多倍体核を形成する.
- これらの細胞は,その後アポトーシスを経験します.
結論:
- p21WAF1/CIP1は,ヒト細胞のSとM相の調整に必要であり,重要なチェックポイントの調節器として作用する.
- p21WAF1/CIP1機能の喪失は,S/M相解離,ゲノム不安定,細胞死につながる.
- このメカニズムの理解は,臨床的に使用されるDNAを損傷する薬剤が同様のS/M解離を引き起こす可能性があるため,がん治療に役立つかもしれません.
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