Deep sequencing identifies new and regulated microRNAs in Schmidtea mediterranea

RNA. 2009 Aug;15(8):1483-91. doi: 10.1261/rna.1702009. Epub 2009 Jun 24.


MicroRNAs (miRNAs) play important roles in directing the differentiation of cells down a variety of cell lineage pathways. The planarian Schmidtea mediterranea can regenerate all lost body tissue after amputation due to a population of pluripotent somatic stem cells called neoblasts, and is therefore an excellent model organism to study the roles of miRNAs in stem cell function. Here, we use a combination of deep sequencing and bioinformatics to discover 66 new miRNAs in S. mediterranea. We also identify 21 miRNAs that are specifically expressed in either sexual or asexual animals. Finally, we identified five miRNAs whose expression is sensitive to gamma-irradiation, suggesting they are expressed in neoblasts or early neoblast progeny. Together, these results increase the known repertoire of S. mediterranea miRNAs and identify numerous regulated miRNAs that may play important roles in regeneration, homeostasis, neoblast function, and reproduction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Gamma Rays
  • Genome, Helminth
  • MicroRNAs / chemistry
  • MicroRNAs / genetics*
  • MicroRNAs / radiation effects
  • Models, Biological
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Planarians / cytology
  • Planarians / genetics*
  • Planarians / physiology
  • Pluripotent Stem Cells / physiology
  • Pluripotent Stem Cells / radiation effects
  • RNA, Helminth / chemistry
  • RNA, Helminth / genetics*
  • RNA, Helminth / radiation effects
  • Regeneration / genetics
  • Regeneration / physiology
  • Sequence Analysis, RNA
  • Species Specificity


  • MicroRNAs
  • RNA, Helminth