The Kolodkin lab reports in Science
The Kolodkin lab reports in Science that signaling between the transmembrane guidance cue semaphorin 6A (Sema6A) and its receptor plexinA2 (PlexA2) regulates dendritic morphology of On, but not Off, starburst amacrine cells, thereby controlling direction-selective responses to visual stimuli in the mouse.
Direction-selective responses to visual cues depend upon precise connectivity between inhibitory starburst amacrine cells (SACs) and direction-selective ganglion cells (DSGCs). Motion is detected by SAC responses to illumination onset (On) or cessation (Off). On and Off SACs costratify in the inner plexiform layer of the vertebrate retina with distinct DSGC dendritic arborizations that mediate On or Off directional responses. Here, we study the molecular mechanisms that specify On versus Off SACs and the signaling pathways governing the functional assembly of murine retinal direction-selective circuitry. We show that signaling between the transmembrane guidance cue semaphorin 6A (Sema6A) and its receptor plexinA2 (PlexA2) regulates dendritic morphology of On but not Off SACs, thereby controlling direction-selective responses to visual stimuli.