Invertebrate Neuroscience

, 15:4 | Cite as

Decrease in levels of the evolutionarily conserved microRNA miR-124 affects oligodendrocyte numbers in Zebrafish, Danio rerio

  • Jacqueline K. Morris
  • Anthony Chomyk
  • Ping Song
  • Nate Parker
  • Sadie Deckard
  • Bruce D. Trapp
  • Sanjay W. Pimplikar
  • Ranjan Dutta
Original Paper


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.


Danio rerio miR-124 Neuron Oligodendrocyte miRNA 



The authors would like to thank Dr. Stephen Stohlman for his comments and Dr. Christopher Nelson for manuscript editing.

Compliance with Ethical Standards


The work was supported by a Grant from the National Multiple Sclerosis Society, USA (RG-4280 to RD), and Baldwin Wallace University Faculty Development award (JKM).

Conflict of interests



  1. Akerblom M, Jakobsson J (2013) MicroRNAs as neuronal fate determinants. Neuroscientist 20(3):235–242CrossRefPubMedGoogle Scholar
  2. Akerblom M, Sachdeva R, Barde I, Verp S, Gentner B, Trono D, Jakobsson J (2012) MicroRNA-124 is a subventricular zone neuronal fate determinant. J Neurosci 32:8879–8889PubMedCentralCrossRefPubMedGoogle Scholar
  3. Barres BA, Raff MC (1993) Proliferation of oligodendrocyte precursor cells depends on electrical activity in axons. Nature 361:258–260CrossRefPubMedGoogle Scholar
  4. Bercury KK, Macklin WB (2015) Dynamics and mechanisms of CNS myelination. Dev Cell 32:447–458CrossRefPubMedGoogle Scholar
  5. Brosamle C, Halpern ME (2002) Characterization of myelination in the developing zebrafish. Glia 39:47–57CrossRefPubMedGoogle Scholar
  6. Cao X, Pfaff SL, Gage FH (2007) A functional study of miR-124 in the developing neural tube. Genes Dev 21:531–536PubMedCentralCrossRefPubMedGoogle Scholar
  7. Cheng LC, Pastrana E, Tavazoie M, Doetsch F (2009) miR-124 regulates adult neurogenesis in the subventricular zone stem cell niche. Nat Neurosci 12:399–408PubMedCentralCrossRefPubMedGoogle Scholar
  8. Chomczynski P, Sacchi N (1987) Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem 162:156–159CrossRefPubMedGoogle Scholar
  9. Clark AM, Goldstein LD, Tevlin M, Tavare S, Shaham S, Miska EA (2010) The microRNA miR-124 controls gene expression in the sensory nervous system of Caenorhabditis elegans. Nucleic Acids Res 38:3780–3793PubMedCentralCrossRefPubMedGoogle Scholar
  10. Czopka T, Ffrench-Constant C, Lyons DA (2013) Individual oligodendrocytes have only a few hours in which to generate new myelin sheaths in vivo. Dev Cell 25:599–609PubMedCentralCrossRefPubMedGoogle Scholar
  11. Dugas JC, Cuellar TL, Scholze A, Ason B, Ibrahim A, Emery B, Zamanian JL, Foo LC, McManus MT, Barres BA (2010) Dicer1 and miR-219 Are required for normal oligodendrocyte differentiation and myelination. Neuron 65:597–611PubMedCentralCrossRefPubMedGoogle Scholar
  12. Dutta R, Chomyk AM, Chang A, Ribaudo MV, Deckard SA, Doud MK, Edberg DD, Bai B, Li M, Baranzini SE, Fox RJ, Staugaitis SM, Macklin WB, Trapp BD (2013) Hippocampal demyelination and memory dysfunction are associated with increased levels of the neuronal microRNA miR-124 and reduced AMPA receptors. Ann Neurol 73:637–645PubMedCentralCrossRefPubMedGoogle Scholar
  13. Emery B (2010) Regulation of oligodendrocyte differentiation and myelination. Science 330:779–782CrossRefPubMedGoogle Scholar
  14. Fields RD (2008) Oligodendrocytes changing the rules: action potentials in glia and oligodendrocytes controlling action potentials. Neuroscientist 14:540–543PubMedCentralCrossRefPubMedGoogle Scholar
  15. Franke K, Otto W, Johannes S, Baumgart J, Nitsch R, Schumacher S (2012) miR-124-regulated RhoG reduces neuronal process complexity via ELMO/Dock180/Rac1 and Cdc42 signalling. EMBO J 31:2908–2921PubMedCentralCrossRefPubMedGoogle Scholar
  16. Giraldez AJ, Cinalli RM, Glasner ME, Enright AJ, Thomson JM, Baskerville S, Hammond SM, Bartel DP, Schier AF (2005) MicroRNAs regulate brain morphogenesis in zebrafish. Science 308:833–838CrossRefPubMedGoogle Scholar
  17. Hartline DK (2008) What is myelin? Neuron Glia Biol 4:153–163CrossRefPubMedGoogle Scholar
  18. Higashijima S, Hotta Y, Okamoto H (2000) Visualization of cranial motor neurons in live transgenic zebrafish expressing green fluorescent protein under the control of the islet-1 promoter/enhancer. J Neurosci 20:206–218PubMedGoogle Scholar
  19. Kapsimali M, Kloosterman WP, De Bruijn E, Plasterk RH, Wilson SW (2007) MicroRNAs show a wide diversity of expression profiles in the developing and mature central nervous system. Genome Biol 8:R173PubMedCentralCrossRefPubMedGoogle Scholar
  20. Krichevsky AM, Sonntag KC, Isacson O, Kosik KS (2006) Specific microRNAs modulate embryonic stem cell-derived neurogenesis. Stem Cells 24:857–864PubMedCentralCrossRefPubMedGoogle Scholar
  21. Lim LP, Lau NC, Garrett-Engele P, Grimson A, Schelter JM, Castle J, Bartel DP, Linsley PS, Johnson JM (2005) Microarray analysis shows that some microRNAs downregulate large numbers of target mRNAs. Nature 433:769–773CrossRefPubMedGoogle Scholar
  22. Mastronardi FG, Moscarello MA (2005) Molecules affecting myelin stability: a novel hypothesis regarding the pathogenesis of multiple sclerosis. J Neurosci Res 80:301–308CrossRefPubMedGoogle Scholar
  23. Nave KA (2010) Myelination and the trophic support of long axons. Nat Rev Neurosci 11:275–283CrossRefPubMedGoogle Scholar
  24. Nave K-A, Trapp BD (2008) Axon-glial signaling and the glial support of axon function. Annu Rev Neurosci 31:535–561CrossRefPubMedGoogle Scholar
  25. Preston MA, Macklin WB (2015) Zebrafish as a model to investigate CNS myelination. Glia 63:177–193CrossRefPubMedGoogle Scholar
  26. Rajasethupathy P, Fiumara F, Sheridan R, Betel D, Puthanveettil SV, Russo JJ, Sander C, Tuschl T, Kandel E (2009) Characterization of small RNAs in Aplysia reveals a role for miR-124 in constraining synaptic plasticity through CREB. Neuron 63:803–817PubMedCentralCrossRefPubMedGoogle Scholar
  27. Sanuki R, Onishi A, Koike C, Muramatsu R, Watanabe S, Muranishi Y, Irie S, Uneo S, Koyasu T, Matsui R, Cherasse Y, Urade Y, Watanabe D, Kondo M, Yamashita T, Furukawa T (2011) miR-124a is required for hippocampal axogenesis and retinal cone survival through Lhx2 suppression. Nat Neurosci 14:1125–1134CrossRefPubMedGoogle Scholar
  28. Schumacher S, Franke K (2013) miR-124-regulated RhoG: A conductor of neuronal process complexity. Small GTPases 4:42–46PubMedCentralCrossRefPubMedGoogle Scholar
  29. Silber J, Lim DA, Petritsch C, Persson AI, Maunakea AK, Yu M, Vandenberg SR, Ginzinger DG, James CD, Costello JF, Bergers G, Weiss WA, Alvarez-Buylla A, Hodgson JG (2008) miR-124 and miR-137 inhibit proliferation of glioblastoma multiforme cells and induce differentiation of brain tumor stem cells. BMC Med 6:14PubMedCentralCrossRefPubMedGoogle Scholar
  30. Smirnova L, Grafe A, Seiler A, Schumacher S, Nitsch R, Wulczyn FG (2005) Regulation of miRNA expression during neural cell specification. Eur J Neurosci 21:1469–1477CrossRefPubMedGoogle Scholar
  31. Song P, Pimplikar SW (2012) Knockdown of amyloid precursor protein in zebrafish causes defects in motor axon outgrowth. PLoS One 7:e34209PubMedCentralCrossRefPubMedGoogle Scholar
  32. Sun Y, Luo ZM, Guo XM, Su DF, Liu X (2015) An updated role of microRNA-124 in central nervous system disorders: a review. Front Cell Neurosci 9:193PubMedCentralCrossRefPubMedGoogle Scholar
  33. Thisse C, Thisse B (2008) High-resolution in situ hybridization to whole-mount zebrafish embryos. Nat Protoc 3:59–69CrossRefPubMedGoogle Scholar
  34. Weng R, Cohen SM (2012) Drosophila miR-124 regulates neuroblast proliferation through its target anachronism. Development 139:1427–1434CrossRefPubMedGoogle Scholar
  35. Zeller J, Granato M (1999) The zebrafish diwanka gene controls an early step of motor growth cone migration. Development 126:3461–3472PubMedGoogle Scholar
  36. Zuchero JB, Barres BA (2013) Intrinsic and extrinsic control of oligodendrocyte development. Curr Opin Neurobiol 23:914–920PubMedCentralCrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Department of BiologyBaldwinWallace UniversityBereaUSA
  2. 2.Department of Neuroscience, Lerner Research InstituteCleveland Clinic FoundationClevelandUSA

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