Neurexins regulate presynaptic GABAB-receptors at central synapses
Fujun Luo1,2, Alessandra Sclip3, Sean Merrill3
1Department of Molecular and Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, CA, USA. luo_fujun@grmh-gdl.cn.
Nature Communications
|April 23, 2021
Summary
Neurexins are essential for organizing GABAB-receptor signaling complexes at the presynaptic active zone. Their absence impairs neurotransmitter release regulation and receptor localization, highlighting neurexins as key organizers.
Area of Science:
- Neuroscience
- Molecular Biology
- Synaptic Function
Background:
- Presynaptic active zones assemble diverse signaling complexes crucial for synaptic transmission and plasticity.
- GABAB-receptors are key regulators of neurotransmitter release, but their assembly mechanisms are not fully understood.
Purpose of the Study:
- To elucidate the molecular mechanisms governing the assembly of GABAB-receptor signaling complexes at the presynaptic active zone.
- To investigate the role of neurexins in the localization and function of these complexes.
Main Methods:
- Investigated neurexin function across four distinct model synapses (calyx of Held, hippocampal CA1, cerebellar basket cell synapses).
- Utilized genetic deletion of neurexins to assess impacts on neurotransmitter release sensitivity and receptor localization.
Main Results:
- Deletion of neurexins significantly reduced neurotransmitter release sensitivity to GABAB-receptor activation at all tested synapses.
- Neurexin deficiency led to the loss of GABAB-receptors from the presynaptic active zone, particularly observed at calyx synapses.
Conclusions:
- Neurexins are indispensable for the proper localization and function of presynaptic GABAB-receptor signaling complexes.
- These findings establish neurexins as central organizers of active zone signaling, extending their role beyond previously known functions.
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