新しい145kDの脳細胞性タンパク質は,透過性神経内分泌細胞のCa2+) 調節分泌を再構成する
J H Walent1, B W Porter, T F Martin
1Department of Zoology, University of Wisconsin, Madison 53706.
Cell
|September 4, 1992
まとめ
研究者らは,神経内分泌細胞のカルシウム活性化分泌に不可欠な新しい脳タンパク質,p145を特定しました. このタンパク質,p145は,カルシウム信号を膜融合イベントに変換する上で重要な役割を果たしています.
科学分野:
- 神経生物学 神経生物学とは
- 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:
- 調節された分泌経路は,細胞のコミュニケーションとホルモンの放出に不可欠です.
- カルシウムイオン (Ca2+) は,この経路のトリガーとして知られていますが,特定の分子プレーヤーはほとんど不明です.
研究 の 目的:
- 分泌経路のカルシウム (Ca2+) 調節を媒介するサイトゾール成分を特定する.
- Ca2+活性化分泌に関与する新発見のタンパク質の機能と性質を特徴づける.
主な方法:
- 半完全な神経内分泌細胞を使って,Ca2+活性化分泌を研究した.
- 新型タンパク質p145.5を特定し,特徴づけるために生化学的測定法を使用した.
- 分泌におけるp145の役割を評価するためにp145固有の抗体を用いた.
主要な成果:
- 新しい脳タンパク質であるp145を,神経内分泌細胞におけるCa2+活性化分泌を回復する細胞分裂因子として特定した.
- p145は145 kDaのサブユニットのダイマーで,フォスフォリピドベシクルを結合し,Ca2+依存の方法で水嫌性マトリックスと相互作用します.
- p145に対する抗体は,Ca2+活性化分泌物の再構成を阻害し,その重要な役割を確認した.
結論:
- p145は,調節された分泌経路におけるCa2+シグナル伝達の重要な媒介である.
- タンパク質の性質は,Ca2+信号を膜融合に変換する膜関連機能を示唆しています.
- 分泌組織におけるp145の制限された発現は,この基本的な細胞過程におけるその特定の役割を強調しています.
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