アルファニューレキシンがCa2+チャネルをカップル化し,シナプス膀エクソサイトーシスへと導きます
Markus Missler1, Weiqi Zhang, Astrid Rohlmann
1Center for Basic Neuroscience, Department of Molecular Genetics, Dallas, Texas 75390-9111, USA.
Nature
|June 27, 2003
まとめ
アルファニューレキシンは,シナプス機能に不可欠であり,カルシウムによって引き起こされる神経伝達物質の放出を可能にするために,シナプス前端を組織します. これらのタンパク質は,カルシウムチャネルと放出機構の結合に不可欠であり,効率的なシナプス伝達を確保します.
科学分野:
- 神経科学は神経科学である.
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- シナプスは,複雑な分子組織を含む神経細胞のコミュニケーションに不可欠です.
- アルファニューレキシンは,シナプス前とシナプス後のコンパートメントを結びつけるシナプス前細胞粘着分子です.
- シナプス解離機構の組織化におけるアルファニューレキシンの正確な役割は不明である.
研究 の 目的:
- シナプスの形成と機能におけるアルファニューレキシンの役割を調査する.
- アルファニューレキシンがカルシウム誘発の神経伝達物質の放出にどのように影響するかを決定するために.
- アルファニューレキシンがプレシナプス端末を組織するメカニズムを解明する.
主な方法:
- アルファニューレキシン遺伝子が欠けているトリプルノックアウトマウスを利用した.
- 評価されたシナプス形成と神経伝達物質の放出.
- 定量化された細胞表面カルシウムチャネル数と機能.
主要な成果:
- アルファニューレキシンはシナプス形成に不可欠ではありません.
- シナプス伝達とカルシウム誘発の神経伝達物質の放出は,ノックアウトマウスでは著しく低下しています.
- プレシナプスカルシウムチャネル機能は,正常な表面表現にもかかわらず,著しく低下しています.
結論:
- アルファニューレキシンは,シナプス形成ではなく,適切なシナプス機能に不可欠です.
- これらのタンパク質は,プレシナプス端末の組織化において重要な役割を果たします.
- アルファニューレキシンは,カルシウムチャネルを神経伝達物質の放出機構に機能的に結合させます.
関連する概念動画
01:12Synaptic Signaling
Neurons communicate at synapses, or junctions, to excite or inhibit the activity of other neurons or target cells, such as muscles. Synapses may be chemical or electrical.
01:26Fusion of Secretory Vesicles with the Plasma Membrane
Proteins and neurotransmitters in secretory vesicles can be released from a cell upon vesicle docking, priming, and fusion with the plasma membrane. Vesicles are docked and primed in preparation for the quick exocytosis of their contents in response to a stimulus. The fusion process is mainly carried out by a SNAP Receptor or SNARE complex, consisting of synaptobrevin, syntaxin-1, and SNAP-25.
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
01:30Ligand-Gated Ion Channel Receptor: Gating Mechanism
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
01:27Adrenergic Neurons: Neurotransmission
Postganglionic sympathetic fibers (except those supplying the sweat glands) releasing noradrenaline or norepinephrine are called noradrenergic or adrenergic neurons. Noradrenaline, dopamine, adrenaline, or epinephrine are collectively called "catecholamines" as they contain a catechol moiety and an amine side chain. The five stages of neurotransmitter release involve their synthesis, storage, release, reuptake and metabolism.
Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...