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bioRxiv · 10.1101/485888

Bioinformatic analysis of long-lasting transcriptional and translational changes in the basolateral amygdala following acute stress

Abstract

Stress profoundly impacts the brain and increases the risk of developing a psychiatric disorder. The brains response to stress is mediated by a number of pathways that affect gene expression and protein function throughout the cell. Understanding how stress achieves such dramatic effects on the brain requires an understanding of the brains stress response pathways. The majority of studies focused on molecular changes have employed repeated or chronic stress paradigms to assess the long-term consequences of stress and have not taken an integrative genomic and/or proteomic approach. Here, we determined the lasting impact of a single stressful event (restraint) on the broad molecular profile of the basolateral amygdala complex (BLC), a key brain region mediating emotion, memory and stress. Molecular profiling performed thirty days post-restraint consisted of small RNA sequencing, RNA sequencing and quantitative mass spectrometry and identified long-lasting changes in microRNA (miRNA), messenger RNA (mRNA) and proteins. Alignment of the three datasets further delineated the regulation of stress-specific pathways which were validated by qPCR and Western Blot analysis. From this analysis, mir-29a-5p was identified as a putative regulator of stress-induced adaptations in the BLC. Further, a number of predicted mir-29a-5p targets are regulated at the mRNA and protein level. The concerted and long-lasting disruption of multiple molecular pathways in the amygdala by a single stress event is expected to be sufficient to alter behavioral responses to a wide array of future experiences, including exposure to additional stressors.

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BibTeXRIS

Sillivan, S. E., Jones, M. E., Jamieson, S., Rumbaugh, G., Miller, C. A.. 2018-12-04. Bioinformatic analysis of long-lasting transcriptional and translational changes in the basolateral amygdala following acute stress. https://doi.org/10.1101/485888

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