Drosophila larval to pupal switch under nutrient stress requires IP3R/Ca2+ signalling in glutamatergic interneurons
- Tata Institute of Fundamental Research, India
- Janelia Research Campus, Howard Hughes Medical Institute, United States
Abstract
Neuronal circuits are known to integrate nutritional information, but the identity of the circuit components is not completely understood. Amino acids are a class of nutrients that are vital for the growth and function of an organism. Here, we report a neuronal circuit that allows Drosophila larvae to overcome amino acid deprivation and pupariate. We find that nutrient stress is sensed by the class IV multidendritic cholinergic neurons. Through live calcium imaging experiments, we show that these cholinergic stimuli are conveyed to glutamatergic neurons in the ventral ganglion through mAChR. We further show that IP3R-dependent calcium transients in the glutamatergic neurons convey this signal to downstream medial neurosecretory cells (mNSCs). The circuit ultimately converges at the ring gland and regulates expression of ecdysteroid biosynthetic genes. Activity in this circuit is thus likely to be an adaptation that provides a layer of regulation to help surpass nutritional stress during development.
Article and author information
Author details
Funding
National Centre for Biological Sciences (Core funding)
- Gaiti Hasan
Council of Scientific and Industrial Research (Graduate fellowship)
- Siddharth Jayakumar
National Centre for Biological Sciences (Graduate fellowship)
- Shlesha Richhariya
Howard Hughes Medical Institute
- Michael Texada
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Jayakumar et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Drosophila larval to pupal switch under nutrient stress requires IP3R/Ca2+ signalling in glutamatergic interneurons
eLife 5:e17495.
https://doi.org/10.7554/eLife.17495
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