Local processing in neurites of VGluT3-expressing amacrine cells differentially organizes visual information.

Jen-Chun Hsiang,Linda Madisen,Keith P Johnson,Daniel Kerschensteiner,Hongkui Zeng

doi:10.7554/elife.31307

Abstract

Neurons receive synaptic inputs on extensive neurite arbors. How information is organized across arbors and how local processing in neurites contributes to circuit function is mostly unknown. Here, we used two-photon Ca2+ imaging to study visual processing in VGluT3-expressing amacrine cells (VG3-ACs) in the mouse retina. Contrast preferences (ON vs. OFF) varied across VG3-AC arbors depending on the laminar position of neurites, with ON responses preferring larger stimuli than OFF responses. Although arbors of neighboring cells overlap extensively, imaging population activity revealed continuous topographic maps of visual space in the VG3-AC plexus. All VG3-AC neurites responded strongly to object motion, but remained silent during global image motion. Thus, VG3-AC arbors limit vertical and lateral integration of contrast and location information, respectively. We propose that this local processing enables the dense VG3-AC plexus to contribute precise object motion signals to diverse targets without distorting target-specific contrast preferences and spatial receptive fields.

Highlights

Neurons receive most of their synaptic input on large intricately branched dendritic arborizations.Traditionally, distributed inputs were thought to be summed linearly at the cell body (Yuste, 2011).recent studies uncovered extensive local processing and clustered plasticity of synaptic inputs that enhance the computational power of dendrites (Grienberger et al, 2015, Harvey and Svoboda, 2007, Kleindienst et al, 2011, London and Hausser, 2005, Losonczy et al, 2008)
We used two-photon Ca2+ imaging in a novel transgenic mouse line to analyze how stimulus contrast, size, and motion are processed in VGluT318 expressing amacrine cells (VG3-Amacrine cells (ACs)) neurites
Staining for VGluT3 confirmed that GCaMP6f labeling in the inner nuclear layer (INL) and the inner plexiform layer (IPL) of

Summary

Introduction

Neurons receive most of their synaptic input on large intricately branched dendritic arborizations.Traditionally, distributed inputs were thought to be summed linearly at the cell body (Yuste, 2011).recent studies uncovered extensive local processing and clustered plasticity of synaptic inputs that enhance the computational power of dendrites (Grienberger et al, 2015, Harvey and Svoboda, 2007, Kleindienst et al, 2011, London and Hausser, 2005, Losonczy et al, 2008). We used two-photon Ca2+ imaging in a novel transgenic mouse line to analyze how stimulus contrast, size, and motion are processed in VG3-AC neurites.

Results

Conclusion