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Puthanveettil, S.

Publications and source records attributed to Puthanveettil, S..

3 recordsLinked to original sources

PKA Activity-Driven Modulation of Bidirectional Long-Distance transport of Lysosomal vesicles During Synapse Maintenance

The bidirectional long-distance transport of organelles is crucial for cell body-synapse communication. However, the mechanisms by which this transport is modulated for synapse formation, maintenance, and plasticity are not fully understood. Here, we demonstrate through quantitative analyses that maintaining sensory neuron-motor neuron synapses in the Aplysia gill-siphon withdrawal reflex is linked to a sustained reduction in the retrograde transport of lysosomal vesicles in sensory neurons. Interestingly, while mitochondrial transport in the anterograde direction increases within 12 hours of synapse formation, the reduction in lysosomal vesicle retrograde transport appears three days after synapse formation. Moreover, we find that formation of new synapses during learning induced by neuromodulatory neurotransmitter serotonin further reduces lysosomal vesicle transport within 24 hours, whereas mitochondrial transport increases in the anterograde direction within one hour of exposure. Pharmacological inhibition of several signaling pathways pinpoints PKA as a key regulator of retrograde transport of lysosomal vesicles during synapse maintenance. These results demonstrate that synapse formation leads to organelle-specific and direction specific enduring changes in long-distance transport, offering insights into the mechanisms underlying synapse maintenance and plasticity.

neuroscience↗

lncRNA ADEPTR loss-of-function elicits sex-specific behavioral and spine deficits

Activity-dependent changes in neuronal connections are fundamental to learning and long-term memory storage. However, the precise contribution of long noncoding RNAs (lncRNAs) to these modifications remains unclear. In this study, we assessed the role of the lncRNA ADEPTR, a cAMP-modulated lncRNA localized in dendrites, which is crucial for synapse morphology. By generating two different mouse models--one with a deletion of ADEPTR (L-ADEPTR) and one with a deletion of its protein interaction region (S-ADEPTR)--we investigated the sex-specific impacts of ADEPTR loss of function on learning, memory, dendritic arborization, and synapse morphology. Our behavioral analyses revealed a reduction in anxiety in adult male mice, while learning and memory remained unaffected in both models. Systematic evaluations of neuronal morphology across various developmental stages ([~]3-day-old postnatal neuronal cultures and postnatal 14- and 42-day-old male and female mice) uncovered substantial deficits in neuronal architecture in both S- and L-ADEPTR male and female neuronal cultures. At postnatal day 42, in contrast to their male counterparts, L-ADEPTR female mice exhibited a significant deficiency in thin spines. Additionally, we found that the expression of plasticity-related gene BDNF, and immediate early gene cFOS were enhanced in both the cortex and hippocampus of adult male and female S- and L-ADEPTR mice, suggesting the activation of a compensatory mechanism protecting against learning and memory deficits. Collectively, these observations underscore the sex-specific role of lncRNA ADEPTR in shaping neuronal morphology and anxiety behavior.

neuroscience↗

A cAMP/PKA-dependent synaptically targeted lncRNA mediates structural plasticity in hippocampal neurons by functionally interacting with the Spectrin/Ankyrin Network

Activity-dependent structural plasticity at the synapse requires specific changes in the neuronal transcriptome. While much is known about the role of coding elements in this process, the role of the long-noncoding transcriptome remains elusive. Here we report the discovery of an intronic long noncoding RNA (lncRNA)--termed ADEPTR--whose expression is upregulated and is synaptically transported in a cAMP/PKA-dependent manner in hippocampal neurons, independent of its protein-coding host gene. Loss of ADEPTR function suppresses activity-dependent changes in synaptic transmission and structural plasticity of dendritic spines. Mechanistically, dendritic localization of ADEPTR is mediated by molecular motor protein Kif2A. ADEPTR physically binds to actin-scaffolding regulators Ankyrin (AnkB) and Spectrin (Sptn1) and is required for their dendritic localization. Taken together, this study demonstrates that ADEPTR regulates the dendritic Spectrin-Ankyrin network for structural plasticity at the synapse and illuminates a novel role for lncRNAs at the synapse. One Sentence SummaryWe have uncovered an intronic long noncoding RNA that is synaptically transported in a cAMP-dependent manner and is linked to cytoskeletal components of structural plasticity in hippocampal neurons.

neuroscience↗