人間の癌細胞におけるAPOBEC3変異のメカニズム
Mia Petljak1, Alexandra Dananberg2, Kevan Chu2
1Broad Institute of MIT and Harvard, Cambridge, MA, USA. mpetljak@broadinstitute.org.
Nature
|July 21, 2022
まとめ
内生APOBEC3酵素は癌の変異を誘導する. APOBEC3Aを削除すると,シグネチャが減少し,APOBEC3Bを削除すると,APOBEC3Aの活性が増加し,重要な突然変異のメカニズムが明らかになりました.
科学分野:
- 遺伝学
- 分子生物学
- 癌 研究
背景:
- APOBEC3 (アポリプロテインB mRNA編集酵素,触媒性ポリペプチド型3) 細胞酸脱アミナゼのファミリーは,一般的な癌の変異シグネチャーに関連しています.
- APOBEC3変異のメカニズムとヒトがんゲノムにおけるその因果的な役割は,まだ十分に理解されていません.
研究 の 目的:
- ヒトの癌細胞系におけるAPOBEC3変異のメカニズムを調査する.
- 内生APOBEC3酵素と癌の変異シグネチャーの間の直接的な因果関係を確立する.
主な方法:
- 人間の癌細胞系におけるAPOBEC3AとAPOBEC3Bの遺伝子削除
- 251の癌細胞系クローン (乳房,膀,リンパ腫) の全ゲノム配列解析
- APOBEC3媒介による変異におけるUNGとREV1の役割の評価
主要な成果:
- APOBEC3Aの削除はAPOBEC3に関連した変異シグネチャを大幅に減少させた.
- APOBEC3AとAPOBEC3Bを併せて削除すると,突然変異の負荷は減ったが,排除されなかった.
- APOBEC3Aタンパク質の濃度,活性,および変異を上位に調節した.
結論:
- 固有のAPOBEC3デアミナゼは,ヒトの癌細胞に直接的な変異シグネチャを生成する.
- APOBEC3Aはこれらの変異の主な原動力として特定されています.
- APOBEC3BはAPOBEC3Aの活性を調節し,独自の変異を寄与する.UNGとREV1は特定の変異タイプで役割を果たします.
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