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Moffat, J. J.

Publications and source records attributed to Moffat, J. J..

3 recordsLinked to original sources

Prosapip1 in the dorsal hippocampus mediates synaptic protein composition, long-term potentiation, and spatial memory

Prosapip1 is a brain-specific protein localized to the postsynaptic density, where it promotes dendritic spine maturation in primary hippocampal neurons. However, nothing is known about the role of Prosapip1 in vivo. To examine this, we utilized the Cre-loxP system to develop a Prosapip1 neuronal knockout mouse. We found that Prosapip1 controls the synaptic localization of its binding partner SPAR, along with PSD-95 and the GluN2B subunit of the NMDA receptor (NMDAR) in the dorsal hippocampus (dHP). We next sought to identify the potential contribution of Prosapip1 to the activity and function of the NMDAR and found that Prosapip1 plays an important role in NMDAR-mediated transmission and long-term potentiation (LTP) in the CA1 region of the dHP. As LTP is the cellular hallmark of learning and memory, we examined the consequences of neuronal knockout of Prosapip1 on dHP-dependent memory. We found that global or dHP-specific neuronal knockout of Prosapip1 caused a deficit in learning and memory whereas developmental, locomotor, and anxiety phenotypes were normal. Taken together, Prosapip1 in the dHP promotes the proper localization of synaptic proteins which, in turn, facilitates LTP driving recognition, social, and spatial learning and memory.

neuroscience↗

Male mice carrying the BDNF Val68Met polymorphism exhibit alcohol preferences versus social interaction and acute tolerance through malfunction of BDNF in the ventral hippocampus

The brain-derived neurotrophic factor (BDNF) Valine 66 to Methionine human polymorphism results in impaired activity-dependent BDNF release and has been linked to psychiatric disorders including depression and anxiety. We previously showed that male knock-in mice carrying the mouse Methionine homolog (Met68BDNF) exhibit excessive and compulsive alcohol drinking behaviors as compared to the wild-type Val68BDNF mice. Here, we set out to determine the potential mechanism for the heightened and compulsive alcohol drinking phenotypes detected in Met68BDNF mice. We found that male, but not female Met68BDNF mice exhibit social anxiety-like behaviors. We further show that male Met68BDNF mice exhibit a preference for alcohol over social interaction. In contrast, alcohol place preference without an alternative social reward, is similar in male Met68BDNF and Val68BDNF mice. Since the Met68BDNF mice show social anxiety phenotypes, we tested whether alcohol reliefs anxiety similarly in Met68BDNF and Val68BDNF mice and found that male, but not female Met68BDNF mice are insensitive to the acute anxiolytic action of alcohol. Finally, we show that this acute tolerance to alcohol-dependent anxiolysis can be restored by overexpressing wild-type Val68BDNF in the ventral hippocampus (vHC) of Met68BDNF mice. Together, our results suggest that excessive alcohol drinking in the Met68BDNF may be attributed, in part, to heighted social anxiety and a lack of alcohol-dependent anxiolysis, a phenotype that is associated with malfunction of BDNF signaling in the vHC of male Met68BDNF mice.

neuroscience↗

BRAIN-DERIVED NEUROTROPHIC FACTOR IN AN ORBITOFRONTAL CORTICAL-DORSOLATERAL STRIATAL CIRCUIT GATES ALCOHOL CONSUMPTION

Brain-derived neurotrophic factor (BDNF) signaling in the dorsolateral striatum (DLS) gates alcohol self-administration in rodents. The major source of BDNF in the striatum is the cortex, and we recently found that BDNF-expressing neurons in the ventrolateral orbitofrontal cortex (vlOFC) extend axonal projections to the DLS. We therefore hypothesized that BDNF in the vlOFC to DLS circuit moderates alcohol intake. We show that overexpression of BDNF in the vlOFC, which activates BDNF signaling in the DLS, is sufficient to attenuate voluntary consumption and seeking of 20% alcohol in the home cage using a two-bottle choice paradigm. Overexpressing BDNF in the vlOFC had no effect on the consumption of a sweetened saccharin solution. In addition, BDNF overexpression in the neighboring motor cortex did not alter alcohol intake. Finally, pathway-specific overexpression of BDNF in DLS-projecting vlOFC neurons significantly reduced alcohol intake and preference. Overall, BDNF in the vlOFC, and specifically in a vlOFC-DLS pathway, keeps alcohol drinking in moderation.

neuroscience↗