Remodeling of an identified motoneuron during metamorphosis: Central and peripheral actions of ecdysteroids during regression of dendrites and motor terminals

Laura M. Knittel, Karla S. Kent

Research output: Contribution to journalArticle

5 Scopus citations


During metamorphosis of the moth Manduca sexta, an identified leg motoneuron, the femoral depressor motoneuron (FeDe MN), undergoes reorganization of its central and peripheral processes. This remodeling is under the control of two insect hormones: the ecdysteroids and juvenile hormone (JH). Here, we asked whether peripheral or central actions of the ecdysteroids influenced specific regressive aspects of MN remodeling. We used stable hormonal mimics to manipulate the hormonal environment of either the FeDe muscle or the FeDe MN soma. Our results demonstrate that motor-terminal retraction and dendritic regression can be experimentally uncoupled, indicating that central actions of ecdysteroids trigger dendritic, regression whereas peripheral actions trigger terminal retraction. Our results further demonstrate that discrete aspects of motor-terminal retraction can also be experimentally uncoupled, suggesting that they also are regulated differently.

Original languageEnglish (US)
Pages (from-to)99-116
Number of pages18
JournalJournal of Neurobiology
Issue number2
StatePublished - Aug 3 2002



  • Insect
  • Manduca
  • Neuromuscular junction
  • Steroid
  • Synapse elimination

ASJC Scopus subject areas

  • Neuroscience(all)
  • Cellular and Molecular Neuroscience

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