Bioinformatic approaches to screening the molecular framework underlying local dendritic mRNA translation

Learning and memory systems within the brain are believed to be the result of molecular events that occur at the synapse. These molecular events control synaptic efficacy – the modulation of the underlying molecular architecture of the synapse to influence the strength or weakness of connections between pre- and postsynaptic neurons. Deficits in any of these molecular processes results in neuronal dysfunction. The Mammalian/Mechanistic Target of Rapamycin Complex (mTORC1) is a protein complex within the brain composed of the serine/threonine kinase mTOR and other interacting proteins. Dysregulation of mTOR disrupts the many processes under its control such as local dendritic translation at the synapse. Since mTOR is at the core of many important signaling pathways, aberrant mTOR activity results in neuronal disease. The network of interactions between these molecular components is vast, forming an interconnected system that is dynamic and directed. In order to better understand the mechanistic nature of these interactions, the application of high-throughput technologies must be employed. Here we utilize multiple bioinformatics approaches combined with high-throughput technologies to clarify the role of mTOR in local dendritic translation. Using mass spectrometry, we provide the first evidence that mTOR bidirectionally controls the expression of over 700 proteins in the cortex, many of which are known to be associated with diseases in which mTOR is overactive (Chapter 2). Our investigations reveal a novel role PARK7 in tuberous sclerosis complex. Furthermore, we use and develop multiple bioinformatics tools to further delineate the nature of the RNA-binding properties of PARK7 and alternative avenues for drug discovery (Chapter 3). Finally, we provide evidence that the Fragile-X Mental Retardation protein sequesters a population of mRNAs involved in trans-synaptic signaling that mTOR translates to remodel the synapse, providing a mechanistic basis for the action of rapidly-acting antidepressants (Chapter 4). Collectively, our work stresses the importance of applying high-throughput technologies to answer long-standing questions in the field of local dendritic translation. Our findings provide new avenues of investigation and research to better understand neuronal disease and synaptic plasticityNeuroscienc