Figure 9: Model of Sema3B function proposing that Sema3B is a CSF-derived extracellular signal secreted by the floor plate in the spinal cord and the roof of the IVth ventricle (including the presumptive choroid plexus) in the hindbrain at E10.5.
CSF-derived Sema3B promotes the planar orientation of neural progenitor division in the spinal cord.
