TY - JOUR
T1 - Slit1a Inhibits Retinal Ganglion Cell Arborization and Synaptogenesis via Robo2-Dependent and -Independent Pathways
AU - Campbell, Douglas S.
AU - Stringham, Sydney A.
AU - Timm, Adam
AU - Xiao, Tong
AU - Law, Mei Yee
AU - Baier, Herwig
AU - Nonet, Michael L.
AU - Chien, Chi Bin
N1 - Funding Information:
We thank Lara Hutson for the slit1a morpholinos, Andrew Pittman for the isl3 promoter, Benjamin Mangum for the two-photon microscope conversion, Edward Ruthazer for advice for using his Object Image Morphometry macros, the Dorsky lab for use of their microscope and camera, Hitoshi Okamoto and Deborah Yelon for in situ probes, Susan Chapman for advice with sectioning, Reinhard Köster for plasmids, and Sherry Scott for critical reading of the manuscript. We are very grateful to Hitoshi Okamoto in whose laboratory some of the experiments were carried out. Time-lapse imaging was performed at the University of Utah School of Medicine Cell Imaging Facility and at the RIKEN Brain Science Institute. This work was supported by a European Molecular Biology Program Long-Term Fellowship and a Japan Society for the Promotion of Science post-doctoral fellowship (D.S.C.), a Neuroscience training grant postdoctoral fellowship (T.X.), grants from the NIH/NEI (EY12406, EY13855) and March of Dimes (H.B.), grants from the McDonnell Center for Cellular Neuroscience and the National Institutes of Health (M.L.N), and a grant from the NIH/NEI (EY12873, C.-B.C.).
PY - 2007/7/19
Y1 - 2007/7/19
N2 - Upon arriving at their targets, developing axons cease pathfinding and begin instead to arborize and form synapses. To test whether CNS arborization and synaptogenesis are controlled by Slit-Robo signaling, we followed single retinal ganglion cell (RGC) arbors over time. ast (robo2) mutant and slit1a morphant arbors had more branch tips and greater arbor area and complexity compared to wild-type and concomitantly more presumptive presynaptic sites labeled with YFP-Rab3. Increased arborization in ast was phenocopied by dominant-negative Robo2 expressed in single RGCs and rescued by full-length Robo2, indicating that Robo2 acts cell-autonomously. Time-lapse imaging revealed that ast and slit1a morphant arbors stabilized earlier than wild-type, suggesting a role for Slit-Robo signaling in preventing arbor maturation. Genetic analysis showed that Slit1a acts both through Robo2 and Robo2-independent mechanisms. Unlike previous PNS studies showing that Slits promote branching, our results show that Slits inhibit arborization and synaptogenesis in the CNS.
AB - Upon arriving at their targets, developing axons cease pathfinding and begin instead to arborize and form synapses. To test whether CNS arborization and synaptogenesis are controlled by Slit-Robo signaling, we followed single retinal ganglion cell (RGC) arbors over time. ast (robo2) mutant and slit1a morphant arbors had more branch tips and greater arbor area and complexity compared to wild-type and concomitantly more presumptive presynaptic sites labeled with YFP-Rab3. Increased arborization in ast was phenocopied by dominant-negative Robo2 expressed in single RGCs and rescued by full-length Robo2, indicating that Robo2 acts cell-autonomously. Time-lapse imaging revealed that ast and slit1a morphant arbors stabilized earlier than wild-type, suggesting a role for Slit-Robo signaling in preventing arbor maturation. Genetic analysis showed that Slit1a acts both through Robo2 and Robo2-independent mechanisms. Unlike previous PNS studies showing that Slits promote branching, our results show that Slits inhibit arborization and synaptogenesis in the CNS.
KW - DEVBIO
KW - MOLNEURO
UR - http://www.scopus.com/inward/record.url?scp=34447310566&partnerID=8YFLogxK
U2 - 10.1016/j.neuron.2007.06.034
DO - 10.1016/j.neuron.2007.06.034
M3 - Article
C2 - 17640525
AN - SCOPUS:34447310566
SN - 0896-6273
VL - 55
SP - 231
EP - 245
JO - Neuron
JF - Neuron
IS - 2
ER -