Send to

Choose Destination
Cell Rep. 2017 Dec 12;21(11):3049-3064. doi: 10.1016/j.celrep.2017.11.044.

Strict Independence of Parallel and Poly-synaptic Axon-Target Matching during Visual Reflex Circuit Assembly.

Author information

Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94304, USA.
Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94304, USA; Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA 94303, USA; Bio-X, Stanford University, Stanford, CA 94305, USA. Electronic address:


The use of sensory information to drive specific behaviors relies on circuits spanning long distances that wire up through a range of axon-target recognition events. Mechanisms assembling poly-synaptic circuits and the extent to which parallel pathways can "cross-wire" to compensate for loss of one another remain unclear and are crucial to our understanding of brain development and models of regeneration. In the visual system, specific retinal ganglion cells (RGCs) project to designated midbrain targets connected to downstream circuits driving visuomotor reflexes. Here, we deleted RGCs connecting to pupillary light reflex (PLR) midbrain targets and discovered that axon-target matching is tightly regulated. RGC axons of the eye-reflex pathway avoided vacated PLR targets. Moreover, downstream PLR circuitry is maintained; hindbrain and peripheral components retained their proper connectivity and function. These findings point to a model in which poly-synaptic circuit development reflects independent, highly stringent wiring of each parallel pathway and downstream station.


Tbr2; Tph2; axon competition; axon-target matching; ipRGC; olivary pretectal nucleus; pretectum; pupillary light reflex; retina; subcortical

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center