Publications by authors named "Stephen Janoschka"

In neurons, intracellular membrane rafts are essential for specific actions of brain-derived neurotrophic factor (BDNF), which include the regulation of axon outgrowth, growth cone turning and synaptic transmission. Virtually, all the actions of BDNF are mediated by binding to its receptor, TrkB. The association of TrkB with the tyrosine kinase, Fyn, is critical for its localization to intracellular membrane rafts.

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Parkinson's disease (PD) is characterized by the degeneration of nigral dopaminergic (DA) neurons and non-DA neurons in many parts of the brain. Mutations of parkin, an E3 ubiquitin ligase that strongly binds to microtubules, are the most frequent cause of recessively inherited PD. The lack of robust PD phenotype in parkin knockout mice suggests a unique vulnerability of human neurons to parkin mutations.

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Accumulating evidence suggests that global depletion of adult hippocampal neurogenesis influences its function and that the timing of the depletion affects the deficits. However, the behavioral roles of adult-born neurons during their establishment of projections to CA3 pyramidal neurons remain largely unknown. We used a combination of retroviral and optogenetic approaches to birth date and reversibly control a group of adult-born neurons in adult mice.

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Plasticity in the adult brain enables lifelong learning. The fundamental mechanism of adult neural plasticity is activity-dependent reorganization of pre-existing structure, in contrast to the widespread cellular proliferation and migration that occurs during development. Whereas adult hippocampal dentate gyrus continuously generates cohorts of neurons, and newborn neurons integrate into the existing neural circuit under the regulation of existing global and local neural activity, demonstrating a unique cellular and synaptic flexibility in adult brain.

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The sequential synaptic integration of adult-born neurons has been widely examined in rodents, but the mechanisms regulating the integration remain largely unknown. The primary cilium, a microtubule-based signaling center, is essential for vertebrate development, including the development of the CNS. We examined the assembly and function of the primary cilium in the synaptic integration of adult-born mouse hippocampal neurons.

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Neurogenesis occurs in adult mammalian brains in the sub-ventricular zone (SVZ) of the lateral ventricle and in the sub-granular zone (SGZ) of the hippocampal dentate gyrus throughout life. Previous reports have shown that adult hippocampal neurogenesis is associated with diverse brain disorders, including epilepsy, schizophrenia, depression and anxiety (1). Deciphering the process of normal and aberrant adult-born neuron integration may shed light on the etiology of these diseases and inform the development of new therapies.

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Biofluorescence exists in only a few classes of organisms, with Anthozoa possessing the majority of species known to express fluorescent proteins. Most species within the Anthozoan subgroup Scleractinia (reef-building corals) not only express green fluorescent proteins, they also localize the proteins in distinct anatomical patterns.We examined the distribution of biofluorescence in 33 coral species, representing 8 families, from study sites on Australia's Great Barrier Reef.

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Synapsin III is a synaptic vesicle-associated protein that is expressed in cells of the subgranular layer of the hippocampal dentate gyrus, a brain region known to sustain substantial levels of neurogenesis into adulthood. Here we tested the hypothesis that synapsin III plays a role in adult neurogenesis with synapsin III knockout and wild-type mice. Immunocytochemistry of the adult hippocampal dentate gyrus revealed that synapsin III colocalizes with markers of neural progenitor cell development (nestin, PSA-NCAM, NeuN, and Tuj1) but did not colocalize with markers of mitosis (Ki67 and PCNA).

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