ヒストンH3-H4テトラメアは,銅還元酵素である

Narsis Attar^1,2, Oscar A Campos^1,2, Maria Vogelauer¹

¹Department of Biological Chemistry, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.

Science (New York, N.Y.)

|July 8, 2020

まとめ

ユカリオットヒストンH3-H4テトラメルは,銅を結合および還元する酸化還元酵素である. この新しい機能は細胞の銅レベルと核細胞の銅に依存したプロセスに影響します

科学分野:

生物化学
細胞生物学
分子生物学

背景:

ユカリオットヒストンH3-H4テトラメアは,定義されていない役割を持つ二分化界面に銅 (Cu2+) の結合部位を有する.
ユカリオットの進化的出現は,大気中の酸素の増加と一致し,細胞の銅管理に課題をもたらした.

研究の目的:

ヒストンH3-H4テトラメアの銅結合部位の機能を調査する.
ヒストンが細胞のコッパー・ホメオスタシスに作用するかどうかを判断する.

主な方法:

リコンビナントのXenopus laevis H3- H4テトラメアは,コッパー結合と還元を in vitro で研究するために使用されました.
機能喪失と機能獲得の変異は,Saccharomyces cerevisiaeの銅の代謝と機能への影響を分析するために導入されました.

主要な成果:

リコンビナンスのH3-H4テトラメアは,Cu²⁺をCu¹⁺に還元し,酸化還元酵素の活性を示した.
推定活性部位における突然変異は,酵素結合,酵素活性,細胞内Cu¹⁺レベル,および酵母における銅に依存したミトコンドリア呼吸およびSod1機能を変化させた.

結論:

ヒストンH3-H4テトラメアは,クロマチンの凝縮と表遺伝学的調節を超えた新しい酵素的機能を有する.
これらのテトラメアは,生物学的利用可能なCu¹⁺イオンを生成し,真核生物における細胞銅の恒常化に寄与する.

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