Mohrmann, L.; Seebach, J.; Missler, M.; Rohlmann, A. Distinct Alterations in Dendritic Spine Morphology in the Absence of β-Neurexins. Int. J. Mol. Sci.2024, 25, 1285.
Mohrmann, L.; Seebach, J.; Missler, M.; Rohlmann, A. Distinct Alterations in Dendritic Spine Morphology in the Absence of β-Neurexins. Int. J. Mol. Sci. 2024, 25, 1285.
Mohrmann, L.; Seebach, J.; Missler, M.; Rohlmann, A. Distinct Alterations in Dendritic Spine Morphology in the Absence of β-Neurexins. Int. J. Mol. Sci.2024, 25, 1285.
Mohrmann, L.; Seebach, J.; Missler, M.; Rohlmann, A. Distinct Alterations in Dendritic Spine Morphology in the Absence of β-Neurexins. Int. J. Mol. Sci. 2024, 25, 1285.
Abstract
Dendritic spines are essential for synaptic function because they constitute the neurons' postsynaptic compartment that receives the most excitatory input. The extracellularly shorter variant of the presynaptic cell adhesion molecules neurexins, β-neurexins, has been implicated in various aspects of synapse function including neurotransmitter release. However, its role in developing or stabilizing dendritic spines as fundamental computational units of excitatory synapses remained unclear. Here, we show by morphological analysis that the deletion of β-neurexins in hippocampal neurons in vitro and in hippocampal tissue in vivo affects presynaptic dense-core vesicles and, unexpectedly, postsynaptic spine structure. Specifically, we observed that the absence of β-neurexins led to an increase in longer spinous protrusions in vitro and more mature mushroom-type spines in the CA1 region of adult knockout mice. In addition, deletion of β-neurexins caused alterations in spine head dimension and more spines with perforations of their postsynaptic density but no change in the overall number of spines or synapses. Our results indicate that presynaptic β-neurexins play a role across the synaptic cleft, possibly by aligning with postsynaptic binding partners and glutamate receptors via transsynaptic columns.
Keywords
cell-adhesion molecules; synaptic plasticity; mushroom spine; 3D reconstruction; perforated PSD, transmission electron microscopy; dense-core vesicles; mouse; hippocampus
Subject
Biology and Life Sciences, Neuroscience and Neurology
Copyright:
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