神経伝達物質の分泌の欠如で脳のシナプスアセンブリ
まとめ
Munc18-1タンパク質が欠けているマウスは,神経伝達物質を分泌することができないが,それでも脳構造を形成する. これは,神経伝達物質の分泌は初期脳組成に不可欠ではないことを示唆しますが,シナプス結合の維持と神経変異の予防に不可欠です.
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.
- 発達生物学 発達生物学について
背景:
- ニューロンの接続性は,脳の機能に不可欠です.
- シナプスの形成は,軸索から分泌される信号を含むと考えられています.
- 脳の発達と維持における神経伝達物質の分泌の役割は完全に理解されていません.
研究 の 目的:
- 神経伝達物質の分泌におけるMunc18-1の役割と,脳の発達とシナプス結合に及ぼす影響を調査する.
- 神経伝達物質の分泌が,ニューロン構造の初期形成に不可欠であるか,または長期的な維持に不可欠であるかどうかを判断する.
主な方法:
- Munc18-1遺伝子の削除によるマウスモデルを使用しました.
- 層構造や繊維経路を含む脳アセンブリを観察した.
- 評価されたシナプス形成とニューロンの生存/退化.
主要な成果:
- Munc18-1 が欠けていたマウスは,神経伝達物質の分泌を完全に失っていた.
- 分泌の欠如にもかかわらず,シナプス形成を含む正常な脳の組み立てが起こりました.
- これらのマウスのニューロンはアポトーシスを経験し,組み立て段階の後の神経変性につながった.
結論:
- シナプス接続性は,その初期確立のために神経伝達物質の分泌に厳密に依存するものではありません.
- 神経伝達物質の分泌は,確立されたシナプス結合の維持に不可欠です.
- 神経伝達物質の分泌は,既存のシナプス結合を検証し,その分解を防止する役割を果たす可能性があります.
関連する概念動画
Synaptic 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.
The Synapse
Neurons communicate with one another by passing on their electrical signals to other neurons. A synapse is the location where two neurons meet to exchange signals. At the synapse, the neuron that sends the signal is called the presynaptic cell, while the neuron that receives the message is called the postsynaptic cell. Note that most neurons can be both presynaptic and postsynaptic, as they both transmit and receive information.
Fusion 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...
Synaptic 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.
Most synapses are chemical, meaning an electrical impulse or action potential spurs the release of chemical messengers called neurotransmitters. The neuron sending the signal is called the presynaptic neuron, and the neuron receiving the signal is the postsynaptic neuron.
The presynaptic neuron fires an action potential that...
Most synapses are chemical, meaning an electrical impulse or action potential spurs the release of chemical messengers called neurotransmitters. The neuron sending the signal is called the presynaptic neuron, and the neuron receiving the signal is the postsynaptic neuron.
The presynaptic neuron fires an action potential that...
Chemical 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...
Chemical 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...


