oncogene v-fmsによってコードされたグリコプロテインのトランスメブラン方向性
Cell
|April 1, 1985
まとめ
レトロウイルス性腫瘍遺伝子のv-fmsグリコタンパク質は,細胞変異のために細胞膜輸送を必要とします. その膜を横断するセグメントは,成長因子受容体と同様のシグナル伝達に不可欠なタンパク質の方向性を決定します.
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
- 腫瘍学 腫瘍学
背景:
- レトロウイルス腫瘍遺伝子のv-fmsは,細胞変異に不可欠なグリコタンパク質をコードする.
- このグリコプロテインをプラズマ膜に適切に輸送することは,その腫瘍性機能の前提条件である.
研究 の 目的:
- v-fmsグリコタンパク質の膜を横断するセグメントが,その細胞の局所化と変換活動における役割を調査する.
- v-fmsが細胞変異を誘導するメカニズムを解明する.
主な方法:
- 変形した細胞のマイクロソームからのトリプティック消化産物の分析.
- 予測された膜を横断するペプチドを削除するためのサイト指向型変異.
- バイオケミカルアッセイは,野生型および変異型グリコプロテインのグリコシル化,キナーゼ活性,および細胞の局所性を評価する.
主要な成果:
- 細胞表面エピトープを含むv-fmsの膜で保護されたアミノ端末断片が特定されました.
- 膜を横断するセグメントの削除は,マイクロソームの封じ込めと変換活動の喪失をもたらしました.
- 変異したグリコプロテインは,変化したグリコシル化を示し,インビトロキナーゼ活性が欠如し,細胞表面輸送に失敗しました.
結論:
- v-fmsの膜横断セグメントは,グリコタンパク質のトポロジーを制御し,信号伝導のためのドメインを指向します.
- v-fmsは,成長因子受容体を模倣する異常なシグナル伝達経路を通じて細胞を変化させる可能性が高い.
- v-fmsの構造-機能を理解することは,腫瘍学的メカニズムと標的療法にとって非常に重要です.
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