Protocadherin-dependent dendritic self-avoidance regulates neural connectivity and circuit function
- Harvard University, United States
Abstract
Dendritic and axonal arbors of many neuronal types exhibit self-avoidance, in which branches repel each other. In some cases, these neurites interact with those of neighboring neurons, a phenomenon called self/non-self discrimination. The functional roles of these processes remain unknown. Here, we used retinal starburst amacrine cells (SACs), critical components of a direction-selective circuit, to address this issue. In SACs, both processes are mediated by the gamma-protocadherins (Pcdhgs), a family of 22 recognition molecules. We manipulated Pcdhg expression in SACs and recorded from them and their targets, direction-selective ganglion cells (DSGCs). SACs form autapses when self-avoidance is disrupted and fail to form connections with other SACs when self/non-self discrimination is perturbed. Pcdhgs are also required to prune connections between closely spaced SACs. These alterations degrade the direction selectivity of DSGCs. Thus, self-avoidance, self/non-self discrimination, and synapse elimination are essential for proper function of a circuit that computes directional motion.
Article and author information
Author details
Reviewing Editor
- Kang Shen, Howard Hughes Medical Institute, Stanford University, United States
Ethics
Animal experimentation: Animals were used in accordance with NIH guidelines and protocols approved by Institutional Animal Use and Care Committee at Harvard University (IACUC protocol #24-10).Animals were euthanized by intraperitoneal injection of pentobarbital or euthasol.
Version history
- Received: May 24, 2015
- Accepted: July 2, 2015
- Accepted Manuscript published: July 3, 2015 (version 1)
- Version of Record published: August 25, 2015 (version 2)
Copyright
© 2015, Kostadinov & Sanes
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Protocadherin-dependent dendritic self-avoidance regulates neural connectivity and circuit function
eLife 4:e08964.
https://doi.org/10.7554/eLife.08964
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