関連する実験動画
Updated: Jul 14, 2026
11:42
Measurement of Total Calcium in Neurons by Electron Probe X-ray Microanalysis
Published on: November 20, 2013
主に海馬のCA3細胞で発現する高親和性カイナート受容体のクローン化
P Werner1, M Voigt, K Keinänen
1Laboratory of Molecular Neuroendocrinology, Centre for Molecular Biology, University of Heidelberg, Germany.
Nature
|June 27, 1991
まとめ
研究者らは,KA-1という新しいラット遺伝子を特定し,カイナート刺激毒性に関与している. この遺伝子は,カイナートに対する高い親和性を持つ受容体をコードし,中枢神経系ニューロン敏感性および神経変性におけるその役割を示唆しています.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- 薬理学 薬理学とは
背景:
- カイン酸は,刺激性アミノ酸受容体に作用する神経毒です.
- カイナート受容体の理解は,神経刺激毒性と中枢神経系機能の研究に不可欠です.
研究 の 目的:
- 新しいカイネート受容体のサブユニットを特定し,特徴づけること.
- 新しく発見されたKA-1という遺伝子の神経毒性における役割を調査する.
主な方法:
- ネズミのKA-1遺伝子の遺伝子クローニングとシーケンシング.
- 再結合KA-1の発現と,放射性リガンド結合アッセイ ([3H]カイナート) を用いた薬理学的特徴づけ.
- ネズミの脳領域 (海馬) でのKA-1mRNA発現の分析. in situハイブリッド化を用いた.
主要な成果:
- KA-1遺伝子は,AMPA受容体サブユニットと30%のシーケンスの類似性を持つ新しい刺激性アミノ酸受容体サブユニットをコードする.
- 発現したKA-1はカイナート (Kd ≈ 5 nM) に対して高い親和性を示し,クローンされたAMPA受容体と区別する.
- KA-1 mRNAは,海馬のCA3領域で高度に発現し,高親和性カイナート結合部位と相関しています.
結論:
- KA-1受容体は,哺乳類の脳内の高親和性カイナート結合部位の重要な成分である可能性が高い.
- KA-1は,中枢神経系におけるカイナート誘発性神経毒性を媒介する重要な役割を果たす可能性があります.
- この発見は,エキシト毒性およびカイン酸に対するニューロンの感受性の基礎となる分子機構の洞察を提供します.
関連する概念動画
01:19The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
01:16Calmodulin-dependent Signaling
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The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
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01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
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