György Lonart

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Presynaptic activation of protein kinase A (PKA) induces LTP in cerebellar parallel fiber synapses. Presynaptic LTP is known to require the active zone protein RIM1alpha, but the underlying induction mechanism remains unclear. We now show that PKA directly phosphorylates RIM1alpha at two sites. Using paired recordings from cultured cerebellar granule and(More)
In mossy fiber synapses of the hippocampal CA3 region, LTP is induced by cAMP and requires the synaptic vesicle protein rab3A. In contrast, CA1-region synapses do not exhibit this type of LTP. We now show that cAMP enhances glutamate release from CA3 but not CA1 synaptosomes by (1) increasing the readily releasable pool as tested by hypertonic sucrose; (2)(More)
Exposure to galactic cosmic radiation is a potential health risk in long-term space travel and represents a significant risk to the central nervous system. The most harmful component of galactic cosmic radiation is the HZE [high mass, highly charged (Z), high energy] particles, e.g., (56)Fe particle. In previous ground-based experiments, exposure to doses(More)
Previous studies established that genetic deletion of synapsins, synaptic vesicle-associated phosphoproteins that regulate neurotransmitter release, decreases the number of synaptic vesicles in nerve terminals. To investigate whether these changes affect the release properties of the remaining synaptic vesicles, we used a radioactive labeling technique to(More)
Long-term potentiation (LTP) of granule cell-Purkinje cell synapses in the mouse cerebellum requires phosphorylation by protein kinase A of the active-zone protein RIM1alpha at Ser413. Here, we show that the adapter protein 14-3-3 readily binds phosphorylated Ser413 in RIM1alpha, and that presynaptic transfection with a dominant-negative 14-3-3eta mutant,(More)
Brain-derived neurotrophic factor (BDNF) is known to activate proline-directed Ser/Thr protein kinases and to enhance glutamatergic transmission via a Rab3a-dependent molecular pathway. The identity of molecular targets in BDNF's action on Rab3a pathway, a synaptic vesicle protein involved in vesicle trafficking and synaptic plasticity, is not fully known.(More)
Exposure to galactic cosmic radiation (GCR) is considered to be a potential health risk in long-term space travel, and it represents a significant risk to the central nervous system (CNS). The most harmful component of GCR is the HZE [high-mass, highly charged (Z), high-energy] particles, e.g. (56)Fe. In ground-based experiments, exposure to HZE-particle(More)
Exposure to galactic cosmic radiation (GCR) is considered to be a potential health risk in long-term space travel, and it represents a significant risk to the central nervous system (CNS). The most harmful component of GCR is the HZE [high-mass, highly charged (Z), high-energy] particles, e.g. (56)Fe. In previous ground-based experiments, exposure to high(More)
Previous ground-based experiments have shown that cranial irradiation with mission relevant (20 cGy) doses of 1 GeV/nucleon (56)Fe particles leads to a significant impairment in Attentional Set Shifting (ATSET) performance, a measure of executive function, in juvenile Wistar rats. However, the use of head only radiation exposure and the biological age of(More)
Sleep mechanisms and synaptic plasticity are thought to interact to regulate homeostasis and memory formation. However, the influences of molecules that mediate synaptic plasticity on sleep are not well understood. In this study we demonstrate that mice lacking Rab3 interacting molecule 1 alpha (RIM1 alpha) (Rim1 alpha KO), a protein of the synaptic active(More)