Dicer1 is required for pigment cell and craniofacial development in zebrafish

Biochim Biophys Acta Gene Regul Mech. 2019 Apr;1862(4):472-485. doi: 10.1016/j.bbagrm.2019.02.005. Epub 2019 Mar 3.


The multidomain RNase III endoribonuclease DICER is required for the generation of most functional microRNAs (miRNAs). Loss of Dicer affects developmental processes at different levels. Here, we characterized the zebrafish Dicer1 mutant, dicer1sa9205, which has a single point mutation induced by N-ethyl-N-nitrosourea mutagenesis. Heterozygous dicer1sa9205 developed normally, being phenotypically indistinguishable from wild-type siblings. Homozygous dicer1sa9205 mutants display smaller eyes, abnormal craniofacial development and aberrant pigmentation. Reduced numbers of both iridophores and melanocytes were observed in the head and ventral trunk of dicer1sa9205 homozygotes; the effect on melanocytes was stronger and detectable earlier in development. The expression of microphthalmia-associated transcription factor a (mitfa), the master gene for melanocytes differentiation, was enhanced in dicer1-depleted fish. Similarly, the expression of SRY-box containing gene 10 (sox10), required for mitfa activation, was higher in mutants than in wild types. In silico and in vivo analyses of either sox10 or mitfa 3'UTRs revealed conserved potential miRNA binding sites likely involved in the post-transcriptional regulation of both genes. Based on these findings, we propose that dicer1 participates in the gene regulatory network governing zebrafish melanocyte differentiation by controlling the expression of mitfa and sox10.

Keywords: Neural crest; Zebrafish; miRNAs; sox10.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Animals
  • Apoptosis
  • Cartilage / abnormalities*
  • Cartilage / growth & development
  • Embryo, Nonmammalian / abnormalities
  • Embryo, Nonmammalian / anatomy & histology
  • Gene Expression Regulation
  • Head
  • Larva / anatomy & histology
  • Melanocytes / cytology*
  • Melanocytes / metabolism
  • Microphthalmia-Associated Transcription Factor / genetics
  • Microphthalmia-Associated Transcription Factor / metabolism
  • Monophenol Monooxygenase / metabolism
  • Mutation
  • Neural Crest / cytology
  • Ribonuclease III / genetics
  • Ribonuclease III / physiology*
  • SOXE Transcription Factors / genetics
  • SOXE Transcription Factors / metabolism
  • Zebrafish / embryology
  • Zebrafish / genetics
  • Zebrafish / growth & development
  • Zebrafish / metabolism
  • Zebrafish Proteins / genetics
  • Zebrafish Proteins / metabolism
  • Zebrafish Proteins / physiology*


  • 3' Untranslated Regions
  • Microphthalmia-Associated Transcription Factor
  • SOXE Transcription Factors
  • Zebrafish Proteins
  • mitfa protein, zebrafish
  • sox10 protein, zebrafish
  • Monophenol Monooxygenase
  • Ribonuclease III