Regulation of hunger-driven behaviors by neural ribosomal S6 kinase in Drosophila

Proc Natl Acad Sci U S A. 2005 Sep 13;102(37):13289-94. doi: 10.1073/pnas.0501914102. Epub 2005 Sep 6.

Abstract

Hunger elicits diverse, yet coordinated, adaptive responses across species, but the underlying signaling mechanism remains poorly understood. Here, we report on the function and mechanism of the Drosophila insulin-like system in the central regulation of different hunger-driven behaviors. We found that overexpression of Drosophila insulin-like peptides (DILPs) in the nervous system of fasted larvae suppressed the hunger-driven increase of ingestion rate and intake of nonpreferred foods (e.g., a less accessible solid food). Moreover, up-regulation of Drosophila p70/S6 kinase activity in DILP neurons led to attenuated hunger response by fasted larvae, whereas its down-regulation triggered fed larvae to display motivated foraging and feeding. Finally, we provide evidence that neural regulation of food preference but not ingestion rate may involve direct signaling by DILPs to neurons expressing neuropeptide F receptor 1, a receptor for neuropeptide Y-like neuropeptide F. Our study reveals a prominent role of neural Drosophila p70/S6 kinase in the modulation of hunger response by insulin-like and neuropeptide Y-like signaling pathways.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptation, Physiological
  • Animals
  • Drosophila / physiology*
  • Drosophila Proteins / physiology
  • Feeding Behavior / physiology*
  • Hunger / physiology*
  • Intercellular Signaling Peptides and Proteins / genetics
  • Larva / physiology
  • Neurons / metabolism
  • Receptors, Neuropeptide
  • Ribosomal Protein S6 Kinases, 90-kDa / genetics
  • Ribosomal Protein S6 Kinases, 90-kDa / physiology*
  • Signal Transduction
  • Up-Regulation / physiology

Substances

  • Drosophila Proteins
  • Intercellular Signaling Peptides and Proteins
  • NPFR protein, Drosophila
  • Receptors, Neuropeptide
  • Ribosomal Protein S6 Kinases, 90-kDa