ヒトT細胞白血病ウイルスI型pXタンパク質の核の局所化のための配列要件は,ウイルスのRNA処理を調節するタンパク質です

H Siomi¹, H Shida, S H Nam

¹Institute for Virus Research Kyoto University, Japan.

Cell

|October 21, 1988

まとめ

ヒトT細胞白血病ウイルスI型 (HTLV-I) 調節体p27x-IIIは細胞核を標的とする. 特定のアミノ端末配列は,ハイブリッドタンパク質をこの細胞位置に導きます.

科学分野:

分子生物学は分子生物学である.
ウイルス学ウイルス学ウイルス学
細胞生物学細胞生物学

背景:

ヒトT細胞白血病ウイルスI型 (HTLV-I) は,様々な癌に関与しているレトロウイルスです.
転写後の調節体p27x-IIIは,HTLV-Iの複製と病原化に役割を果たしています.
ウイルスのタンパク質の局所性を理解することは,その機能を解読する上で極めて重要です.

研究の目的:

HTLV-Iの転写後のレギュレータp27x-III.の細胞下部位を調査する.
細胞核にp27x-IIIを誘導する特定のタンパク質配列を特定する.

主な方法:

免疫光を用いたサブセルラー局所化研究.
融合タンパク質構造は,p27x-IIIのアミノ端末配列をレポータータンパク質 (β-ガラクトシダゼおよびp40x) にリンクすることによって作成されました.
細胞内のこれらのハイブリッドタンパク質の局所化の分析.

主要な成果:

HTLV-Iの調節体p27x-IIIは,主に細胞核に存在します.
p27x-IIIの非常に基本的なアミノ端末配列が特定されました.
この配列は自律的な信号として機能し,融合したタンパク質を核に導きます.

結論:

p27x-IIIの核の局所化は,特定のアミノ端末配列によって媒介されます.
この配列は,強力な核の局所化信号 (NLS) として作用します.
この発見は,HTLV-Iタンパク質の細胞内密輸についての洞察を提供します.

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