3'フラップベースのオカザキ断片の成熟は,細胞の生存を支えている

Haitao Sun¹, Zhaoning Lu¹, Amanpreet Singh¹

¹Department of Cancer Genetics and Epigenetics, Beckman Research Institute, City of Hope, 1500 East Duarte Road, Duarte, CA 91010, USA.

Science (New York, N.Y.)

|December 2, 2021

まとめ

DNA複製の欠陥を持つ細胞は,ストレスの下では誤りやすいオカザキ断片の成熟経路を活性化します. この経路は細胞の生存と進化を可能にする内部タンデム複製のような変異を生成します

科学分野:

分子生物学
遺伝学
細胞生物学

背景:

DNA複製の欠陥を持つ細胞は環境ストレスでアポトーシスに直面することが多いのです
これらの細胞が生き残るために変異を起こすメカニズムを理解することは極めて重要です

研究の目的:

ストレス下でのDNA複製欠陥を有する酵母細胞におけるオカザキ断片成熟経路 (OFM) の活性化を調査する.
この経路によって発生する特定の変異と細胞生存におけるその役割を特定する.

主な方法:

使用されたrad27Δ酵母細胞は,制限的な温度ストレスを受ける.
DNAポリメラーゼ δ (Polδ) を含むDun1キナーゼの活性化と3′核酸の役割を分析した.
3′フラップの二次構造の形成とその後のDNA拡張を調査した.

主要な成果:

制限温度でrad27Δ酵母細胞でストレス誘発の誤差を誘発する OFM経路が活性化されました.
この経路は,pol3 の内部タンデム複製のような,短いスペーサー配列を持つ代替複製の形成につながった.
生成された変異は,通常,ストレス下でのrad27Δによって誘発される致死性を抑制しました.

結論:

ストレスが原因で誤りやすい新しい OFM 経路を定義した.
この経路は細胞の進化と生存を促す複製の欠陥に対抗する特定の変異を生成します
複雑な環境下で細胞が適応し生き残る方法について洞察力を与えてくれます

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