筋肉の発達におけるアセチルコリン受容体の構造的なスイッチ
Huanhuan Li1, Jinfeng Teng1, Ryan E Hibbs2,3
1Department of Neurobiology, University of California San Diego, La Jolla, CA, USA.
Nature
|July 31, 2024
まとめ
研究者らは,胎児と成人におけるニコチンアセチルコリン受容体 (AChR) の構造的基礎を明らかにした. これらの発見は,受容体の違いがシナプスの成熟と高精度筋肉の収縮をどのように可能にするかを説明し,先天性筋縮症候群の洞察を提供します.
科学分野:
- 神経科学
- 構造生物学
- 生物化学
背景:
- モーターニューロンは骨格筋とシナプスを形成し,アセチルコリン (ACh) を放出し,ニコチン ACh受容体 (AChR) に結合する.
- 胎児と成人のACHRイソフォームの差異的発現は,神経筋シナプスの成熟に極めて重要です.
- AChRのタイプ間の切り替えを制御する構造的メカニズムは,ほとんど不明のままです.
研究 の 目的:
- 胎児と成人の筋肉のニコチン AChR の高解像度構造を解明する.
- 神経筋シナプスの発達と機能中のACHRアイソフォームチューニングを理解するための構造的文脈を提供すること.
- 生まれながらの筋縮症候群の 病原性メカニズムを明らかにする
主な方法:
- 胎児および成人の筋肉のニコチン AChR の高解像度構造的決定
- アセチルコリン (ACh) の存在と欠如の構造分析
主要な成果:
- AChの差異は,拘束的な場所のアクセシビリティに起因する.
- チャンネル伝導性は,表面の静電学によって調節されます.
- 開放期間は,サブユニット間の相互作用と構造的柔軟性によって影響されます.
- 生まれながらのミアステニック症候群の病原性メカニズムが特定されました.
結論:
- 胎児および成人のACHRに関する構造的な洞察は,シナプスの発達と筋肉の収縮におけるその役割を説明する.
- これらの構造を理解すると,先天性筋疲労症候群の理解に役立ちます.
- この研究は,神経筋疾患を標的とした将来の治療戦略の基盤を提供します.
さらに関連する動画
11:57Using an α-Bungarotoxin Binding Site Tag to Study GABA A Receptor Membrane Localization and Trafficking
Published on: March 28, 2014
15.8K
12:18The Neuromuscular Junction: Measuring Synapse Size, Fragmentation and Changes in Synaptic Protein Density Using Confocal Fluorescence Microscopy
Published on: December 26, 2014
21.7K
関連する概念動画
01:25Cholinergic Receptors: Muscarinic
2.1K
The pharmacological actions of acetylcholine are elicited via its binding to two families of cholinergic receptors or cholinoceptors, namely, muscarinic and nicotinic receptors. Muscarinic receptors are G protein-coupled receptors and have five subtypes, M1–M5. All mAChR subtypes are activated by acetylcholine and blocked by the antagonist, atropine.
The subtypes M1, M3, and M5 couple with the Gq subunit and activate the phospholipase C (PLC) activity, mobilizing intracellular Ca2+....
The subtypes M1, M3, and M5 couple with the Gq subunit and activate the phospholipase C (PLC) activity, mobilizing intracellular Ca2+....
2.1K
01:26Chemical Synapses
8.8K
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...
8.8K
01:15Muscle Contraction
90.5K
90.5K
01:15Cholinergic Receptors: Nicotinic
2.5K
Nicotinic receptors are ligand-gated ion channels that are activated by acetylcholine and nicotine. Upon activation, they cause a rapid increase in the permeability of cells to K+, Na+, and Ca2+, followed by depolarization and excitation. They are in the autonomic ganglia, skeletal neuromuscular junction, CNS, and adrenal medulla.
There are two types of nicotinic receptors: neuromuscular (NM/NM/N1) and neuronal (NN/NN/N2). The two families differ based on their location and selectivity to...
There are two types of nicotinic receptors: neuromuscular (NM/NM/N1) and neuronal (NN/NN/N2). The two families differ based on their location and selectivity to...
2.5K
01:29Neuromuscular Junction And Blockade
3.0K
The site of chemical communication between a motor neuron and a muscle fiber is called the neuromuscular junction (NMJ). The end of the motor neuron at the NMJ divides into a cluster of synaptic end bulbs. The cytoplasm of these bulbs consists of synaptic vesicles enclosing acetylcholine molecules, the principal neurotransmitter released at the NMJ. The region opposite the synaptic bulb that ends in the muscle fiber is called the motor end plate, which has acetylcholine receptors. Within the...
3.0K
01:23Cholinergic Neurons: Neurotransmission
2.8K
Cholinergic neurotransmission involves the synthesis and the release of acetylcholine (ACh) in order to transmit nerve impulses across the synapse. The process begins with the synthesis of acetyl CoA, a precursor for ACh, from ATP, acetate, and coenzyme A in the mitochondria. Choline, another vital precursor, is transported inside the neuron through choline transporters, including high-affinity choline transporter CHT1, low-affinity choline transporter CTL1, and lower-affinity choline...
2.8K