Although several neural pathways have been implicated in feeding behaviors in mammals [1-7], it remains unclear how the brain coordinates feeding motivations to maintain a constant body weight (BW). Here, we identified a neuropeptide pathway important for the satiety and BW control in Drosophila. Silencing of myoinhibitory peptide (MIP) neurons significantly increased BW through augmented food intake and fat storage. Likewise, the loss-of-function mutation of mip also increased feeding and BW. Suppressing the MIP pathway induced satiated flies to behave like starved ones, with elevated sensitivity toward food. Conversely, activating MIP neurons greatly decreased food intake and BW and markedly blunted the sensitivity of starved flies toward food. Upon terminating the activation protocol of MIP neurons, the decreased BW reverts rapidly to the normal level through a strong feeding rebound, indicating the switch-like role of MIP pathway in feeding. Surprisingly, the MIP-mediated BW decrease occurred independently of sex peptide receptor (SPR), the only known receptor for MIP, suggesting the presence of a yet-unknown MIP receptor. Together, our results reveal a novel anorexigenic pathway that controls satiety in Drosophila and provide a new avenue to study how the brain actively maintains a constant BW.
Bibliographical noteFunding Information:
J.C. was supported by the National Creative Research Initiatives grant through the National Research Foundation of Korea (NRF) funded by Ministry of Science, ICT and Future Planning, Korea (NRF-2010-0018291). Y.-J.K. was supported by NRF grants funded by Ministry of Education, Science and Technology (MEST), Korea (NRF-2013R1A1A2010475 and NRF-2015R1A2A1A10054304) and a “Cooperative Research Program for Agriculture Science & Technology Development” grant (project PJ01168102) funded by the Rural Development Administration, Korea. S.M. was supported by the NRF-2012-Global Ph.D. Fellowship Program and was the recipient of a fellowship from Seoul National University for Fundamental Academic Fields. S.M., J.C., Y.-H.J., and Y.-J.K. were supported by BK21 Plus Programs from MEST, Korea.
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All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Agricultural and Biological Sciences(all)