1. Cross-compartmental Modulation of Dendritic Signals for Retinal Direction Selectivity.
- Author
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Koren D, Grove JCR, and Wei W
- Subjects
- Action Potentials drug effects, Action Potentials physiology, Amino Acids pharmacology, Animals, Animals, Newborn, Cadmium Chloride pharmacology, Calcium Channel Blockers pharmacology, Dendrites drug effects, Excitatory Amino Acid Antagonists pharmacology, Female, Inhibitory Postsynaptic Potentials physiology, Male, Mice, Mice, Inbred C57BL, Mice, Transgenic, Photic Stimulation, Receptors, AMPA genetics, Receptors, AMPA metabolism, Retina physiology, Signal Transduction drug effects, Signal Transduction genetics, Synapses drug effects, Synapses physiology, Xanthenes pharmacology, omega-Conotoxin GVIA pharmacology, Amacrine Cells cytology, Amacrine Cells physiology, Dendrites physiology, Motion Perception physiology, Retina cytology, Signal Transduction physiology
- Abstract
Compartmentalized signaling in dendritic subdomains is critical for the function of many central neurons. In the retina, individual dendritic sectors of a starburst amacrine cell (SAC) are preferentially activated by different directions of linear motion, indicating limited signal propagation between the sectors. However, the mechanism that regulates this propagation is poorly understood. Here, we find that metabotropic glutamate receptor 2 (mGluR2) signaling, which acts on voltage-gated calcium channels in SACs, selectively restricts cross-sector signal propagation in SACs, but does not affect local dendritic computation within individual sectors. mGluR2 signaling ensures sufficient electrotonic isolation of dendritic sectors to prevent their depolarization during non-preferred motion, yet enables controlled multicompartmental signal integration that enhances responses to preferred motion. Furthermore, mGluR2-mediated dendritic compartmentalization in SACs is important for the functional output of direction-selective ganglion cells (DSGCs). Therefore, our results directly link modulation of dendritic compartmentalization to circuit-level encoding of motion direction in the retina., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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