Background: MicroRNAs (miRNAs) are short non-coding RNAs that are emerging as important post-transcriptional regulators of neuronal and synaptic development. The precise impact of miRNAs on presynaptic function and neurotransmission remains, however, poorly understood.
Results: Here, we identify miR-27b-an abundant neuronal miRNA implicated in neurological disorders-as a global regulator of the presynaptic transcriptome. miR-27b influences the expression of three quarters of genes associated with presynaptic function in cortical neurons. Contrary to expectation, a large majority of these genes are up-regulated by miR-27b. This stimulatory effect is mediated by miR-27b-directed silencing of several transcriptional repressors that cooperate to suppress the presynaptic transcriptome. The strongest repressive activity appears to be mediated by Bmi1, a component of the polycomb repressive complex implicated in self-renewal of neural stem cells. miR-27b knockdown leads to reduced synaptogenesis and to a marked decrease in neural network activity, which is fully restored by RNAi-mediated silencing of Bmi1.
Conclusions: We conclude that silencing of Bmi1 by miR-27b relieves repression of the presynaptic transcriptome and supports neurotransmission in cortical networks. These results expand the repressive activity of Bmi1 to genes involved in synaptic function and identify a unique post-transcriptional circuitry that stimulates expression of synaptic genes and promotes synapse differentiation.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5050705 | PMC |
http://dx.doi.org/10.1186/s12864-016-3139-7 | DOI Listing |
Biosci Trends
January 2025
School of Pharmacy, Sungkyunkwan University, Suwon, Korea.
Alzheimer's disease (AD) is the most common type of dementia. Its incidence is rising rapidly as the global population ages, leading to a significant social and economic burden. AD involves complex pathologies, including amyloid plaque accumulation, synaptic dysfunction, and neuroinflammation.
View Article and Find Full Text PDFJ Physiol
December 2024
Department of Pharmacology & Physiology, Georgetown University Medical Center, Washington, D.C., USA.
Alzheimer's disease (AD), the most common form of dementia among the elderly, affects numerous individuals worldwide. Despite advances in understanding the molecular underpinnings of AD pathology, effective treatments to prevent or cure the disease remain elusive. AD is characterized not only by pathological hallmarks such as amyloid plaques and neurofibrillary tangles but also by impairments in synaptic physiology, circuit activity and cognitive function.
View Article and Find Full Text PDFCell Genom
December 2024
Centre Hospitalier Universitaire Sainte-Justine Research Center, Montreal, QC, Canada; Department of Pediatrics, Université de Montréal, Montreal, QC, Canada. Electronic address:
Copy-number variants (CNVs) that increase the risk for neurodevelopmental disorders also affect cognitive ability. However, such CNVs remain challenging to study due to their scarcity, limiting our understanding of gene-dosage-sensitive biological processes linked to cognitive ability. We performed a genome-wide association study (GWAS) in 258,292 individuals, which identified-for the first time-a duplication at 2q12.
View Article and Find Full Text PDFNeuron
January 2025
Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA; McCance Center for Brain Health, Massachusetts General Hospital, Boston, MA 02114, USA. Electronic address:
J Neurosci
November 2024
Institute of Neuroscience, CNR, Vedano al Lambro, Italy.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!