核プラズミンの核標的配列の2つの相互依存の基本ドメイン:二重核標的配列のクラスの一種を特定する

J Robbins¹, S M Dilworth, R A Laskey

¹Zoology Department, University of Cambridge, England.

Cell

|February 8, 1991

まとめ

ポイント変異は,核プラズミンの核標的配列の2つの相互依存する基本ドメインを明らかにした. これらの領域の変異は,輸送の欠陥を拡大し,核の輸入における重要な協力的役割を強調する.

科学分野:

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

背景:

核標的配列 (NTS) は,細胞核へのタンパク質の輸入を媒介する.
核プラズミンは,核輸送とクロマチンの組立に関与する重要なタンパク質です.
NTSの構造と機能の関係を理解することは,核輸入メカニズムを解読する上で極めて重要です.

研究の目的:

核プラズミンの核標的配列内の機能領域を調査する.
NTS内の異なる地域の相互依存性を明らかにする.
他のタンパク質における核標的化に関連する保存モチーフを特定する.

主な方法:

ポイント変異は,核プラズミンNTS.内の特定のアミノ酸を変更するために使用されました.
ミュタゲネシスの後のタンパク質輸送欠陥の分析が行われました.
配列を他の既知の核標的配列と比較した.

主要な成果:

NTS内の相互依存する2つの基本領域が特定されました.
これらのドメイン間の10アミノ酸のスペーサー領域は,突然変異を許容します.
ある基本的な領域の突然変異は,他の領域の突然変異によって引き起こされる輸送欠陥を悪化させた.

結論:

特定された基本ドメインは,核プラズミンの核標的化に不可欠であり,機能的に相互依存しています.
2つの基本的なクラスターからなる保存モチーフは,異なるタンパク質の核輸入に関与しています.
これらの発見は,核タンパク質の輸入の分子基礎についての洞察を提供します.

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