使用子突触向的GCaMP8变体来解决突触事件
Jiawen Chen1,2, Junhao Lin1, Kaikai He1,2
1University of Southern California, Department of Neurobiology, Los Angeles, CA USA.
bioRxiv : the preprint server for biology
|July 4, 2025
概括
下一代遗传编码指标 (GCaMP8) 和分析软件 (CaFire) 现在与化学染料和电生理学相匹配,用于突触成像的速度和灵敏度.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 基因编码的指标 (如GCaMP) 对于可视化神经活动至关重要.
- 与化学染料和电生理学相比,以前的GCaMP版本在速度和灵敏度方面存在局限性,特别是在突触区.
- 这些局限性阻碍了对突触动态的详细分析.
研究的目的:
- 设计下一代基于GCaMP8的指标,以提高突触成像的速度和灵敏度.
- 开发一种用于自动定量信号的新型分析程序.
- 为了验证这些新指标和软件在Drosophila神经肌肉结处的性能.
主要方法:
- 工程和GCaMP8变体的验证,以预突触点,活跃区域和后突触区为目标.
- 开发基于Python的分析程序CaFire,用于自动量化唤起和自发信号.
- 在Drosophila神经肌肉结处进行放射性成像和与化学染料和电生理学记录进行比较.
主要成果:
- 与以前的版本相比,工程设计的GCaMP8传感器表现出了卓越的性能.
- 一个比率测量前联想GCaMP8m传感器准确地捕获了前联想变化,具有高灵敏度和可与化学染料相比的动力学.
- 一个后突触GCaMP8m传感器检测到量子事件,其时间和信号分辨率与电生理学相美.
结论:
- 下一代GCaMP8传感器,当针对突触区时,可以实现与传统方法相比的速度和灵敏度.
- 该CaFire软件可以自动和精确量化突触信号.
- 这些进步为解决突触中的快速动态提供了强大的工具.
相关概念视频
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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...
01:12GPCR Desensitization
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01:21G-Protein Gated Ion Channels
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Sensory organs,...
Sensory organs,...
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...
01:26Chemical 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...
01:28Integration of Synaptic Events
Synaptic integration mainly includes the summation of graded potentials. Graded potentials, regardless of their type, cause subtle alterations in membrane voltage, resulting in either depolarization or hyperpolarization. These incremental changes, when combined or summed, can propel the neuron toward its threshold. Consider, for example, a membrane experiencing a +15 mV shift, causing it to depolarize from -70 mV to -55 mV. In this scenario, graded potentials govern the membrane's ability to...