A microRNA negative feedback loop downregulates vesicle transport and inhibits fear memory
- Howard Hughes Medical Institute, Harvard Medical School, United States
- The City College of the City University of New York, United States
- Harvard Medical School, United States
- Howard Hughes Medical Institute, Boston Children's Hospital, United States
- University of Vermont, United States
- Massachusetts Institute of Technology, United States
Abstract
The SNARE-mediated vesicular transport pathway plays major roles in synaptic remodeling associated with formation of long-term memories, but the mechanisms that regulate this pathway during memory acquisition are not fully understood. Here we identify miRNAs that are up-regulated in the rodent hippocampus upon contextual fear-conditioning and identify the vesicular transport and synaptogenesis pathways as the major targets of the fear-induced miRNAs. We demonstrate that miR-153, a member of this group, inhibits the expression of key components of the vesicular transport machinery, and down-regulates Glutamate receptor A1 trafficking and neurotransmitter release. MiR-153 expression is specifically induced during LTP induction in hippocampal slices and its knockdown in the hippocampus of adult mice results in enhanced fear memory. Our results suggest that miR-153, and possibly other fear-induced miRNAs, act as components of a negative feedback loop that blocks neuronal hyperactivity at least partly through the inhibition of the vesicular transport pathway.
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Funding
Howard Hughes Medical Institute
- Danesh Moazed
Howard Hughes Medical Institute
- Christopher A Walsh
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols of Harvard Medical School. The protocol was approved by the Committee on the Ethics of Animal Experiments of Harvard Medical School. All surgery was performed under sodium pentobarbital anesthesia, and every effort was made to minimize suffering.
Copyright
© 2016, Mathew et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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A microRNA negative feedback loop downregulates vesicle transport and inhibits fear memory
eLife 5:e22467.
https://doi.org/10.7554/eLife.22467
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