We have studied the time course of migratory behavior of cerebellar granule cells in the microwell tissue culture system. [3H]Thymidine served as a marker for particular granule cell generations. When cultured 4 hr after [3H]thymidine injection for 6 days in microwell cultures, labeled granule cells were seen to migrate along fiber bundles expanding between reaggregates called "cables" for 3 to...

The mammalian cerebellum is a highly multimodal structure, receiving inputs from multiple sensory modalities and integrating them during complex sensorimotor coordination tasks. Previously, using cell-type-specific anatomical projection mapping, it was shown that multimodal pathways converge onto individual cerebellar granule cells (Huang et al., 2013). Here we directly measure synaptic current...

Hilar mossy cells are the prominent glutamatergic cell type in the dentate hilus of the dentate gyrus (DG); they have been proposed to have critical roles in the DG network. To better understand how mossy cells contribute to DG function, we have applied new viral genetic and functional circuit mapping approaches to quantitatively map and compare local and long-range circuit connections of mossy...

Aberrant reorganization of dentate granule cell axons, the mossy fibers, occurs in human temporal lobe epilepsy and rodent epilepsy models. Whether this plasticity results from the remodeling of preexisting mossy fibers or instead reflects an abnormality of developing dentate granule cells is unknown. Because these neurons continue to be generated in the adult rodent and their production increa...

Neuregulin (NRG), a growth and differentiation factor that signals via erbB receptor tyrosine kinases, has been shown to have biological effects in both the CNS and the peripheral nervous system. We report here that erbB4 is expressed in mature cerebellar granule cells, where it appears to be concentrated at the granule cell postsynaptic terminals. We also show that one form of NRG, Ig-NRG, pla...

Using patch-clamp techniques, we have followed the attributes of the secretory granules of peritoneal mast cells obtained from rats of different ages. The granule attributes were determined by following the step increases in the cell surface membrane area caused by the exocytosis of the granules in GTP gamma S stimulated mast cells. Our data show that the amount of granule membrane available fo...

The extensive migration of granule cells and the parasagittal organization of Purkinje cells are two prominent features of cerebellar development. Using granule cell markers, we observed that the inward migration of a subset of granule cells occurs in streams that appear to be restricted to specific areas in the developing chick cerebellum. These streams are organized into a stereotypical serie...

Commentary Development of acquired temporal lobe epilepsy (TLE) is accompanied by selective cell loss and reorganization of excitatory synaptic circuits in key brain regions. Of particular research focus, the axons of granule cells in the dentate gyrus (i.e., mossy fibers) have long been known to sprout collaterals and form new excitatory synapses with other granule cells after an epileptogenic...

In humans and experimental animals, structural and functional changes in neural circuits can accompany the development of epilepsy. In the dentate gyrus, seizures enhance adult neurogenesis, but it is unclear to what extent newborn granule cells participate in seizure-induced synaptic reorganization. During the first weeks of their existence, mouse newborn granule cells labeled with enhanced gr...

by a short BrdU pulse, indicating that prevention of Bmi1 downregulation does not drive granule cells back into the cell cycle. No tumours were observed in two aging cohorts of transgenic mice derived from separate founder lines. However, these mice display an increase in astrocytes with the type II morphology in vitro compared to wild-type littermates. Cultures of FACSorted Math1-GFP+ granule ...