ftz-f1 and Hr39 opposing roles on EcR expression during Drosophila mushroom body neuron remodeling

Nat Neurosci. 2011 Jan;14(1):37-44. doi: 10.1038/nn.2700. Epub 2010 Dec 5.


Developmental axon pruning is a general mechanism that is required for maturation of neural circuits. During Drosophila metamorphosis, the larval-specific dendrites and axons of early γ neurons of the mushroom bodies are pruned and replaced by adult-specific processes. We found that the nuclear receptor ftz-f1 is required for this pruning, activates expression of the steroid hormone receptor EcR-B1, whose activity is essential for γ remodeling, and represses expression of Hr39, an ftz-f1 homologous gene. If inappropriately expressed in the γ neurons, HR39 inhibits normal pruning, probably by competing with endogenous FTZ-F1, which results in decreased EcR-B1 expression. EcR-B1 was previously identified as a target of the TGFβ signaling pathway. We found that the ftz-f1 and Hr39 pathway apparently acts independently of TGFβ signaling, suggesting that EcR-B1 is the target of two parallel molecular pathways that act during γ neuron remodeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Drosophila
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila Proteins / physiology*
  • Gene Expression Regulation, Developmental / genetics
  • Gene Expression Regulation, Developmental / physiology*
  • Metamorphosis, Biological / genetics
  • Metamorphosis, Biological / physiology*
  • Mushroom Bodies / growth & development
  • Mushroom Bodies / metabolism*
  • Mutant Proteins / metabolism
  • Mutant Proteins / physiology
  • Neurons / metabolism*
  • Neurons / physiology
  • Receptors, Steroid / genetics
  • Receptors, Steroid / metabolism*
  • Receptors, Steroid / physiology*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • DNA-Binding Proteins
  • Drosophila Proteins
  • Mutant Proteins
  • Receptors, Steroid
  • Transcription Factors
  • ecdysone receptor
  • nuclear hormone receptor FTZ-F1 beta, Drosophila
  • nuclear hormone receptor FTZ-F1, Drosophila