分子クローニングと心臓のサルコレマのNa(+) -Ca2+交換器の機能的発現
D A Nicoll1, S Longoni, K D Philipson
1Department of Medicine, UCLA School of Medicine 90024-1760.
Science (New York, N.Y.)
|October 26, 1990
まとめ
研究者らは,心臓のサルコレム性ナトリウム・カルシウム交換器 (NCX1) の補完的なDNA (cDNA) クローンを特定した. このクローンは,心臓の興奮-収縮結合に不可欠なNa(+) -Ca2+交換器の機能的発現を可能にします.
科学分野:
- 心血管生理学 心血管の生理学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- 心臓のサルコレマのNa(+) -Ca2+交換器は,刺激-収縮結合中の細胞内Ca2+の調節に不可欠です.
- このトランスポーターの分子基礎を理解することは,心臓の機能を研究するために不可欠です.
研究 の 目的:
- 心臓のNa(+) - Ca2+交換タンパク質をコードする補完DNA (cDNA) を識別し,特徴づけること.
- Na(+) -Ca2+トランスポーターの分子研究を可能にするために.
主な方法:
- cDNAライブラリをスクリーニングするためにポリクローン抗体を利用しました.
- RNAのハイブリデーションを評価するために,Northern blot分析を行いました.
- ハイドロパシー分析とシーケンス類似性比較を実施しました.
- 合成ペプチドを生成し,抗体生成と免疫封じ込めを行う.
- 機能表現の研究のために合成RNAをXenopus卵細胞に注入した.
主要な成果:
- Na(+) - Ca2+交換タンパク質をコードするcDNAクローンが特定されました.
- cDNAは7キロ塩基RNAにハイブリッド化し,970アミノ酸の開いた読み取りフレームを含んでいます.
- ハイドロパシー分析は,Na(+) -およびK(+) -依存性ATPaseと配列の類似性を持つ複数のトランスメブランヘリクを示唆しています.
- 抗体は70,120,160 kDaのサルコーレマのタンパク質と反応した.
- cDNAから合成されたRNAは,Xenopusの卵細胞におけるNa(+) -Ca2+交換活動を誘発した.
結論:
- 特定されたcDNAクローンは,心臓のNa(+) -Ca2+交換器を表しています.
- この分子ツールは,機能的表現と心臓の生理学におけるトランスポーターの役割のさらなる調査を可能にします.
さらに関連する動画
07:38Functional Characterization of Na+/H+ Exchangers of Intracellular Compartments Using Proton-killing Selection to Express Them at the Plasma Membrane
Published on: March 30, 2015
11:32Determination of the Relative Cell Surface and Total Expression of Recombinant Ion Channels Using Flow Cytometry
Published on: September 28, 2016
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