テロメア長さの制御は,ヒトのテロメアタンパク質TRF1によって行われます

B van Steensel¹, T de Lange

¹The Rockefeller University, New York 10021, USA.

Nature

|February 20, 1997

まとめ

人間のテロメア-リピート結合因子1 (TRF1) は,テロメア延長の抑制剤として作用する. TRF1は,染色体末端のテロメラーゼ活性を抑制することによってテロメアの長さを安定させます.

科学分野:

分子生物学は分子生物学である.
遺伝学遺伝学とは
細胞生物学細胞生物学

背景:

人間のテロメアは染色体の末端を保護し,細胞分裂によって短縮されます.
テロメア縮小は,がん細胞と不死の細胞のテロメラーゼによって逆転する.
テロメラーゼによるテロメア延長を制限する規制メカニズムがある可能性が高い.

研究の目的:

テロメア長さの調節におけるヒトのテロメア重複結合因子1 (TRF1) の役割を調査する.
TRF1がテロメラーゼによって媒介されるテロメアの延長に影響を与えるかどうかを判断する.

主な方法:

テロメラーゼ陽性HT1080腫瘍細胞におけるTRF1の過剰発現.
支配的な陰性TRF1変異体の発現.
テロメア長さの変化のモニタリング.

主要な成果:

長期にわたるTRF1過剰発現は,テロメアの漸進的な縮小につながった.
支配的な陰性TRF1変異体が誘発したテロメアの延長.
テロメア長さのTRF1の影響は,テロメラーゼ発現レベルとは無関係でした.

結論:

TRF1はテロメア延長抑制剤として作用する.
TRF1は,テロメアの長さを安定させる負のフィードバックループに関与しています.
テロメアに結合するTRF1は,cisにおけるテロメラーゼの作用を抑制し,テロメアの長さを調節する.

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