pp60v-srcの36キロダルトンの基板は,変換に敏感な方法でミリスチル化されます
まとめ
pp60v-srcキナーゼの基質である36kDのタンパク質は,アミド結合を通じてミリスティック酸で改変されます. このミリストイレーションは,ロース・サルコマウイルスに変異した細胞で減少する.
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:
- pp60v-srcキナーゼは,細胞シグナル伝達における重要な酵素である.
- その基質を特定することは,細胞のプロセスを理解するために極めて重要です.
- 34-39 kDのタンパク質は,pp60v-srcキナーゼの主要な細胞内基質である.
研究 の 目的:
- 36kDのタンパク質の共振変異の性質を調査する.
- ミリスティック酸が36kDのタンパク質に共振的に結合しているかどうかを判断する.
- Rous サルコマウイルスに変異した細胞におけるこの変異の変化を調べる.
主な方法:
- [3H]ミリスティック酸による鶏の胚性線維芽細胞 (CEF) のインキュベーション.
- 1次元と2次元におけるドデシル硫酸ナトリウム-ポリアクリルアミドゲル電泳 (SDS-PAGE) を用いた分析.
- クロロフォームメタノール溶解性試験とヒドロキシラミン水解.
主要な成果:
- 36kDのタンパク質は,共結合したミリスティック酸を組み込みました.
- この結合はヒドロキシラミンに耐性があり,アミド結合を示唆している.
- 36kDのタンパク質のミリスチル化は,正常な細胞と比較して,ロース・サルコマウイルス変異のCEFで最大45%まで減少した.
結論:
- 36kDのタンパク質は,アミド結合を通してミリスチル化されます.
- このミリストイレーションは,Rousのサルコマウイルスによって変形した細胞では著しく減少します.
- この発見は,pp60v-srcキナーゼ基板の改変と,ウイルスの変異におけるその変化についての洞察を提供します.
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