Decrease in levels of the evolutionarily conserved microRNA miR-124 affects oligodendrocyte numbers in Zebrafish, Danio rerio.
- Resource Type
- Academic Journal
- Authors
- Morris JK; Department of Biology, BaldwinWallace University, Berea, OH, 44017, USA.; Chomyk A; Song P; Parker N; Deckard S; Trapp BD; Pimplikar SW; Dutta R
- Source
- Publisher: Springer Verlag Country of Publication: Germany NLM ID: 9602489 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1439-1104 (Electronic) Linking ISSN: 13542516 NLM ISO Abbreviation: Invert Neurosci Subsets: MEDLINE
- Subject
- Language
- English
Oligodendrocytes produce multi-lamellar myelin membranes that surround axons in the central nervous system (CNS). Preservation and generation of myelin are potential therapeutic targets for dysmyelinating and demyelinating diseases. MicroRNAs (miRNAs) play a vital role in oligodendrocyte differentiation and overall CNS development. miR-124 is a well-conserved neuronal miRNA with important roles in neuronal differentiation and function. miR-124 levels increase following loss of myelin in both human and rodent brains. While the role of neuronal miR-124 in neurogenesis has been established, its effects on axonal outgrowth and oligodendrocytes are not currently known. We therefore explored the possible effect of selective knockdown of miR-124 in Danio rerio using a morpholino-based knockdown approach. No morphological abnormalities or loss of motor neurons were detected despite loss of axonal outgrowth. Morpholino-based knockdown of miR-124 led to reciprocal increases in mRNA levels of target genes that inhibit axonal and dendritic projections. Importantly, loss of miR-124 led to decreased oligodendrocyte cell numbers and myelination of axonal projections in the ventral hindbrain. Taken together, our results add a new dimension to the existing complexity of neuron-glial relationships and highlight the utility of Danio rerio as a model system to investigate such interactions.