Unipolar (Dendritic) Brush Cells Are Morphologically Complex and Require Tbr2 for Differentiation and Migration.

Previous studies demonstrated specific expression of transcription factor Tbr2 in unipolar brush cells (UBCs) of the cerebellum during development and adulthood. To further study UBCs and the role of Tbr2 in their development we examined UBC morphology in transgenic mouse lines (reporter and lineage tracer) and also examined the effects of Tbr2 deficiency in (MGI: ) conditional knock-out (cKO) mice. In reporter and lineage tracer cerebellum, UBCs exhibited more complex morphologies than previously reported including multiple dendrites, bifurcating dendrites, and up to four dendritic brushes.

Low availability of choline disrupts development and function of the retina.

Adequate supply of choline, an essential nutrient, is necessary to support proper brain development. Whether prenatal choline availability plays a role in development of the visual system is currently unknown. In this study, we addressed the role of choline supply for the development and later function of the retina in a mouse model.

Reduced phosphoCREB in Müller glia during retinal degeneration in mice.

Purpose: The mechanisms that trigger retinal degeneration are not well understood, despite the availability of several animal models with different mutations. In the present report, the mouse, a model for retinitis pigmentosa (RP) that contains a mutation in the gene for PDE6β (), is used to evaluate gliosis, as a marker for retinal stress, and cyclic AMP response element binding protein (CREB) phosphorylation, which may be important early in retinal degeneration.

Methods: Wild-type C57Bl6J and mice raised under cyclic light were examined for changes in gliosis and CREB phosphorylation for approximately 3 weeks beginning at P14 to P17 using immunocytochemistry.

Sox2-Deficient Müller Glia Disrupt the Structural and Functional Maturation of the Mammalian Retina.

Purpose: Müller glia (MG), the principal glial cells of the vertebrate retina, display quiescent progenitor cell characteristics. They express key progenitor markers, including the high mobility group box transcription factor SOX2 and maintain a progenitor-like morphology. In the embryonic and mature central nervous system, SOX2 maintains neural stem cell identity.

SOX2 maintains the quiescent progenitor cell state of postnatal retinal Muller glia.

Within discrete regions of the developing mammalian central nervous system, small subsets of glia become specialized to function as neural stem cells. As a result of their self-renewal and neurogenic capacity, these cells later serve to replenish neurons and glia during persistent or injury-induced adult neurogenesis. SOX2, an HMG box transcription factor, plays an essential role in the maintenance of both embryonic and adult neural progenitors.

Arl13b in primary cilia regulates the migration and placement of interneurons in the developing cerebral cortex.

Coordinated migration and placement of interneurons and projection neurons lead to functional connectivity in the cerebral cortex; defective neuronal migration and the resultant connectivity changes underlie the cognitive defects in a spectrum of neurological disorders. Here we show that primary cilia play a guiding role in the migration and placement of postmitotic interneurons in the developing cerebral cortex and that this process requires the ciliary protein, Arl13b. Through live imaging of interneuronal cilia, we show that migrating interneurons display highly dynamic primary cilia and we correlate cilia dynamics with the interneuron's migratory state.

Expression of histone deacetylases in cellular compartments of the mouse brain and the effects of ischemia.

Drugs that inhibit specific histone deacetylase (HDAC) activities have enormous potential in preventing the consequences of acute injury to the nervous system and in allaying neurodegeneration. However, very little is known about the expression pattern of the HDACs in the central nervous system (CNS). Identifying the cell types that express HDACs in the CNS is important for determining therapeutic targets for HDAC inhibitors and evaluating potential side effects.

Histone deacetylase inhibitors preserve white matter structure and function during ischemia by conserving ATP and reducing excitotoxicity.

The importance of white matter (WM) injury to stroke pathology has been underestimated in experimental animal models and this may have contributed to the failure to translate potential therapeutics into the stroke clinic. Histone deacetylase (HDAC) inhibitors are neuroprotective and also promote neurogenesis. These properties make them ideal candidates for stroke therapy.

Role of interstitial branching in the development of visual corticocortical connections: a time-lapse and fixed-tissue analysis.

We combined fixed-tissue and time-lapse analyses to investigate the axonal branching phenomena underlying the development of topographically organized ipsilateral projections from area 17 to area 18a in the rat. These complementary approaches allowed us to relate static, large-scale information provided by traditional fixed-tissue analysis to highly dynamic, local, small-scale branching phenomena observed with two-photon time-lapse microscopy in acute slices of visual cortex. Our fixed-tissue data revealed that labeled area 17 fibers invaded area 18a gray matter at topographically restricted sites, reaching superficial layers in significant numbers by postnatal day 6 (P6).