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Mahringer, D.

Publications and source records attributed to Mahringer, D..

3 recordsLinked to original sources

Functional correlates of immediate early gene expression in mouse visual cortex

AO_SCPLOWBSTRACTC_SCPLOWDuring visual development, response properties of layer 2/3 neurons in visual cortex are shaped by experience. Both visual and visuomotor experience are necessary to coordinate the integration of bottom-up visual input and top-down motor-related input. Whether visual and visuomotor experience engage different plasticity mechanisms, possibly associated with the two separate input pathways, is still unclear. To begin addressing this, we measured the expression level of three different immediate early genes (IEG) (c-fos, egr1 or Arc) and neuronal activity in layer 2/3 neurons of visual cortex before and after a mouses first visual exposure in life, and subsequent visuomotor learning. We found that expression levels of all three IEGs correlated positively with neuronal activity, but that first visual and first visuomotor exposure resulted in differential changes in IEG expression patterns. In addition, IEG expression levels differed depending on whether neurons exhibited primarily visually driven or motor-related activity. Neurons with strong motor-related activity preferentially expressed EGR1, while neurons that developed strong visually driven activity preferentially expressed Arc. Our findings are consistent with the interpretation that bottom-up visual input and top-down motor-related input are associated with different IEG expression patterns and hence possibly also with different plasticity pathways.

neuroscience↗

Expression of c-Fos and Arc in hippocampal region CA1 marks neurons that exhibit learning-related activity changes

Immediate early genes (IEGs) are transcribed in response to neural activity and necessary for many forms of plasticity. However, the dynamics of their expression during learning, as well as their relationship to neural activity, remain unclear. Here we used two-photon imaging in transgenic mice that express a GFP-tagged variant of Arc or c-Fos and a red-shifted calcium indicator to measure learning-related changes in IEG expression levels and neural activity in hippocampal region CA1 as mice learned to perform a two-alternative forced choice task. Neural activity levels correlated positively with IEG expression levels in vivo. In addition, we found that with learning, a subset of neurons in CA1 increased their responses to the reward-predicting cue, and IEG expression levels early in learning were selectively increased in neurons that would exhibit the strongest learning-related changes. Our findings are consistent with an interpretation of IEG expression levels as markers for experience dependent plasticity.

neuroscience↗

Drosophila female-specific brain neuron elicits persistent position- and direction-selective male-like social behaviors

Latent neural circuitry in the female brain encoding male-like mating behaviors has been revealed in both mice and flies. In Drosophila, a key component of this circuitry consists of the doublesex-expressing pC1 neurons, which were deemed to exist in both sexes and function based on the amount of cells being activated. Here, we identify pC1-alpha, a female-specific subtype of pC1, as responsible for inducing persistent male-like social behaviors in females. We demonstrate that activation of a single pC1-alpha neuron is sufficient for such induction in a position- and direction-selective manner, and activity of pC1-alpha neurons as a whole is indispensable for maintaining normal sexual receptivity. These dual functions of pC1-alpha may require different neurotransmission, with acetylcholine specifically required for the former but not the latter. Our findings suggest that pC1-alpha may be the female counterpart of male P1 due to their shared similarities in morphology, lineage, and social promoting function.

neuroscience↗