Format

Send to

Choose Destination
Nat Neurosci. 2018 Mar;21(3):353-363. doi: 10.1038/s41593-018-0084-6. Epub 2018 Feb 19.

Single excitatory axons form clustered synapses onto CA1 pyramidal cell dendrites.

Author information

1
Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA.
2
Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA, USA. sprustonn@janelia.hhmi.org.

Abstract

CA1 pyramidal neurons are a major output of the hippocampus and encode features of experience that constitute episodic memories. Feature-selective firing of these neurons results from the dendritic integration of inputs from multiple brain regions. While it is known that synchronous activation of spatially clustered inputs can contribute to firing through the generation of dendritic spikes, there is no established mechanism for spatiotemporal synaptic clustering. Here we show that single presynaptic axons form multiple, spatially clustered inputs onto the distal, but not proximal, dendrites of CA1 pyramidal neurons. These compound connections exhibit ultrastructural features indicative of strong synapses and occur much more commonly in entorhinal than in thalamic afferents. Computational simulations revealed that compound connections depolarize dendrites in a biophysically efficient manner, owing to their inherent spatiotemporal clustering. Our results suggest that distinct afferent projections use different connectivity motifs that differentially contribute to dendritic integration.

PMID:
29459763
DOI:
10.1038/s41593-018-0084-6
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center