核からタンパク質を迅速に輸出するための信号の識別

W Wen¹, J L Meinkoth, R Y Tsien

¹Department of Chemistry and Biochemistry, Howard Hughes Medical Institute, University of California, San Diego, La Jolla 92093-0654, USA.

Cell

|August 11, 1995

まとめ

核輸出信号 (NES) は,核からタンパク質の輸送を媒介する. 研究者らは,遺伝子調節に不可欠な核輸出を推進するタンパク質キナーゼ阻害剤 (PKI) の新しいNESを特定しました.

科学分野:

細胞生物学細胞生物学
分子生物学は分子生物学である.
バイオケミストリーバイオケミストリー

背景:

核の輸入は核の局所化信号 (NLS) によって規制されていますが,核の輸出メカニズムは依然として理解されていないままです.
タンパク質キナーゼA (PKA) 触媒サブユニット (C) 核取引は遺伝子発現の調節に不可欠です.

研究の目的:

cAMP依存タンパク質キナーゼ (cAPK) の触媒子単位の核輸出のメカニズムを調査する.
核からC-PKl複合体の流出を起こす核輸出信号 (NES) を特定し,特徴づけること.

主な方法:

特定されたNES配列の融合と結合が異質タンパク質に.
核内のタンパク質の密輸の動態の分析.

主要な成果:

cAPKの熱安定阻害剤 (PKI) 内にある特定の領域 (残基35-49) は,強力なNES.として機能する.
PKIから派生したこのNESは,他のタンパク質と融合しても,迅速な核輸出を媒介する.
NES内の排水性残留物は,その機能にとって極めて重要です.
より短い配列 (残留数37-46) も,NES活性を示しています.
特定されたNESは,SV40 NLSと同等の強さですが,輸出用の機能があります.

結論:

PKIには,C-PKI複合体の核輸出を積極的に推進する機能的なNESが含まれています.
このタンパク質ベースのNESは,RNA関連性とは独立しています.
この調査結果は,積極的な核輸出のメカニズムについての洞察を提供し,核輸入信号の理解を補完します.

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