A role for betaFTZ-F1 in regulating ecdysteroid titers during post-embryonic development in Drosophila melanogaster

Dev Biol. 2005 Jun 1;282(1):84-94. doi: 10.1016/j.ydbio.2005.02.028.

Abstract

Variations in ecdysteroid titers play crucial roles in arthropods by initiating and regulating molting and metamorphosis. The recent identification of genes coding for cytochrome P450 enzymes involved in Drosophila ecdysteroidogenesis provides new molecular tools to investigate the regulation of insect hormone production. In the present study, we used an enzyme immunoassay to show that the molting hormone titer is strictly correlated with the steroidogenic capacity of the ring gland. A temporal correlation between dynamics of ecdysone production and expression of genes encoding steroidogenic enzymes was observed during the third instar, suggesting that the timing of hormone production depends on transcriptional regulation of the biosynthetic enzymes. Using clonal analysis, levels of two steroidogenic enzymes, Phantom (PHM) and Disembodied (DIB), were shown to be very reduced in ftz transcription factor 1 (ftz-f1) mutant ring gland cells whereas there was no effect of the without children (woc) mutation, suggesting that FTZ-F1 regulates phm and dib expression. Since betaFTZ-F1 is the homolog of the vertebrate steroidogenic factor 1 (SF1), which plays a key role in the differentiation of vertebrate steroidogenic organs through transcriptional regulation of steroidogenic enzymes, this study emphasizes the strong parallels between insects and vertebrates with respect to the regulatory mechanisms of steroidogenesis.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cytochrome P-450 Enzyme System / metabolism
  • DNA Primers
  • DNA-Binding Proteins / metabolism*
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / growth & development*
  • Drosophila melanogaster / metabolism
  • Ecdysteroids / biosynthesis*
  • Ecdysteroids / genetics
  • Gene Expression Regulation, Developmental*
  • Gene Expression Regulation, Enzymologic*
  • Immunoenzyme Techniques
  • In Situ Hybridization
  • Insect Proteins
  • Larva / growth & development
  • Larva / metabolism
  • Mixed Function Oxygenases / genetics
  • Molting / physiology*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transcription Factors / metabolism*

Substances

  • DNA Primers
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Ecdysteroids
  • Insect Proteins
  • Transcription Factors
  • nuclear hormone receptor FTZ-F1, Drosophila
  • Cytochrome P-450 Enzyme System
  • Mixed Function Oxygenases
  • Phm protein, Drosophila
  • DIB protein, Drosophila