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On and off retinal circuit assembly by divergent molecular mechanisms.

ABSTRACT: Direction-selective responses to motion can be to the onset (On) or cessation (Off) of illumination. Here, we show that the transmembrane protein semaphorin 6A and its receptor plexin A2 are critical for achieving radially symmetric arborization of On starburst amacrine cell (SAC) dendrites and normal SAC stratification in the mouse retina. Plexin A2 is expressed in both On and Off SACs; however, semaphorin 6A is expressed in On SACs. Specific On-Off bistratified direction-selective ganglion cells in semaphorin 6A(-/-) mutants exhibit decreased tuning of On directional motion responses. These results correlate the elaboration of symmetric SAC dendritic morphology and asymmetric responses to motion, shedding light on the development of visual pathways that use the same cell types for divergent outputs.

SUBMITTER: Sun LO

PROVIDER: S-EPMC3863450 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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On and off retinal circuit assembly by divergent molecular mechanisms.

Sun Lu O LO Jiang Zheng Z Rivlin-Etzion Michal M Hand Randal R Brady Colleen M CM Matsuoka Ryota L RL Yau King-Wai KW Feller Marla B MB Kolodkin Alex L AL

Science (New York, N.Y.) 20131101 6158

Direction-selective responses to motion can be to the onset (On) or cessation (Off) of illumination. Here, we show that the transmembrane protein semaphorin 6A and its receptor plexin A2 are critical for achieving radially symmetric arborization of On starburst amacrine cell (SAC) dendrites and normal SAC stratification in the mouse retina. Plexin A2 is expressed in both On and Off SACs; however, semaphorin 6A is expressed in On SACs. Specific On-Off bistratified direction-selective ganglion cel ...[more]

PMID: 24179230

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