Synaptic Ca2+ channels and neurexins are linked through direct and indirect binding complexes
Nils Hohaus1, Carsten Reissner2, Markus Missler3
1Institute of Anatomy and Molecular Neurobiology, University of Münster, Münster, Germany.
Scientific Reports
|July 15, 2026
Summary
Neurexins (Nrxn) interact with voltage-gated calcium channels (VGCCs) through distinct molecular complexes. These interactions, involving VGCC subunits and scaffold proteins like Mint2, regulate presynaptic calcium influx and neurotransmitter release.
Area of Science:
- Neuroscience
- Molecular Biology
- Cell Biology
Background:
- Presynaptic neurotransmitter release relies on calcium (Ca2+) influx via voltage-gated calcium channels (VGCCs).
- Neurexins (Nrxn) are crucial regulators of neurotransmission and Ca2+ influx, but their direct interactions with VGCC subunits are not well understood.
Purpose of the Study:
- To investigate the physical interactions between VGCC subunits and different Neurexin variants.
- To elucidate the molecular mechanisms by which Neurexins modulate presynaptic Ca2+ influx.
Main Methods:
- Utilized a nanobody-based co-precipitation system to study recombinant VGCC-Nrxn complexes.
- Examined interactions between VGCC α1, α2δ subunits, and Nrxn1α/β variants.
Main Results:
- α2δ-1 and α2δ-3 variants of VGCCs bind distinct CaV2.1/CaV2.2 α1 subunits.
- Nrxn1α interacts with α1 independently of α2δ via Mint2, enhancing Nrxn1α/α2δ complex formation.
- Nrxn1β indirectly associates with CaV2 α1 subunits through Mint2 or CASK proteins.
Conclusions:
- Distinct molecular complexes mediate interactions between Nrxn variants and VGCC subunits.
- These interactions provide novel insights into the regulation of presynaptic Ca2+ influx and neurotransmitter release.
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