オリゴフレニン-1は,X関連精神障害に関与するrhoGAPタンパク質をコードする

P Billuart¹, T Bienvenu, N Ronce

¹INSERM U129-ICGM, Faculté de Médecine Cochin, Paris, France.

Nature

|May 15, 1998

まとめ

研究者らは,X関連精神障害 (MRX) に関連した新遺伝子,オリゴフレンイン-1を特定した. この遺伝子の変異は,重要なシグナル伝達経路を妨害し,男性における脳の発達と認知機能に影響を及ぼします.

科学分野:

遺伝学遺伝学とは
神経科学は神経科学である.
分子生物学は分子生物学である.

背景:

X関連精神障害 (X-linked mental retardation,MRX) は,男性の約0.15-0.3%に影響する一般的な,まだよくわかっていない遺伝的疾患です.
ほとんどのMRX症例の遺伝的根拠は,十以上の遺伝子の潜在的関与にもかかわらず,未だに難解である.

研究の目的:

非特異的なX関連精神障害の新たな遺伝的原因を特定する.
認知障害に関連して,新たに発見された遺伝子とそのタンパク質産物の機能を特徴づける.

主な方法:

MRX.を持つ無親の個体における遺伝子識別と変異分析.
胎児の脳組織における遺伝子発現分析.
ドメイン分析 (rhoGAP) を含むタンパク質の特徴化.

主要な成果:

Xq12で新種の遺伝子であるオリゴフレニン-1が特定され,胎児の脳で高い発現があることが判明しました.
オリゴフレニン-1の機能喪失による異なる変異は,関係のない患者でも発見されました.
オリゴフレニン-1は,Rho-GTPase活性化タンパク質 (rhoGAP) ドメインを持つ91Kタンパク質をコードし,Rho/Ras信号伝達の調節における役割を示唆しています.

結論:

オリゴフレーニン-1およびその関連Ras型GTPaseシグナル伝達経路の欠陥は,MRX.MRXの特徴である認知機能障害に関与しています.
この発見は,精神障害の遺伝的基盤を理解するための新しい分子標的を提供します.

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