プロソマトスタチンのアミノ端末配列は直接細胞内を標的とするが,特異性を処理しない
K A Sevarino1, P Stork, R Ventimiglia
1Department of Medicine, New England Medical Center Hospital, Boston, Massachusetts 02111.
Cell
|April 7, 1989
まとめ
前駆体配列ではなく,細胞因子がソマトスタチンの処理を決定する. ネズミのプレプロソマトスタチン (rPPSS) のN端末残留は,哺乳類の細胞の欠陥を標的とするアングラーフィッシュのプロソマトスタチン-2を正します.
科学分野:
- エンドクリノロジー エンドクリノロジー
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
背景:
- ネズミのプレプロソマトスタチン (rPPSS) はソマトスタチン-14とソマトスタチン-28.を産生する.
- アングラーフィッシュの島は,これらのペプチドのための明確な前駆体 (a(I) PPSS, a(II) PPSS) を生成します.
- 以前は,魚の前駆物の差異処理が観察されていた.
研究 の 目的:
- アングラーフィッシュのプレプロソマトスタチン-1と -2.2の間の異なる処理の基礎を調査する.
- 細胞因子または前駆体配列がソマトスタチンの処理パターンを決定するかどうかを判断する.
- 適切なターゲティングと処理を担当する前駆体内の領域を特定します.
主な方法:
- 感染した哺乳類内分泌細胞系が,魚のプレプロソマトスタチン-1 (a(I) PPSS) と -2 (a(II) PPSS) 発現ベクトルを持つ.
- 哺乳類の細胞におけるアングラーフィッシュの前駆体両方の処理パターンを分析した.
- ネズミのプレプロソマトスタチン (rPPSS) 要素とアングラーフィッシュのプロソマトスタチン-2を融合させるハイブリッドタンパク質を構成し,発現した.
主要な成果:
- a(I) PPSSとa(II) PPSSは,哺乳類の細胞で同じように処理され,細胞因子が処理を制御することを示しています.
- 処理されていないアングラーフィッシュのプロソマトスタチン-2は,同様の加工場所にもかかわらず,構成的に分泌されました.
- a(II) PPSSに融合したrPPSSのN端末残基を持つハイブリッドタンパク質が,適切に処理され,制御された経路で分泌されました.
結論:
- 固有の前駆体差異ではなく,細胞的要因が,ソマトスタチンの処理パターンを支配する.
- ネズミのプレプロソマトスタチンのN端末78の残留物は,適切な標的と処理のための信号を含んでいます.
- これらの発見は,差異的なソマトスタチン前駆体処理の基礎にある分子機構を明らかにします.
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