Delivery of circulating lipoproteins to specific neurons in the Drosophila brain regulates systemic Insulin signaling
Abstract
The Insulin signaling pathway couples growth, development and lifespan to nutritional conditions. Here, we demonstrate a function for the Drosophila lipoprotein LTP in conveying information about dietary lipid composition to the brain to regulate Insulin signaling. When yeast lipids are present in the diet, free calcium levels rise in Blood Brain Barrier glial cells. This induces transport of LTP across the Blood Brain Barrier by two LDL receptor-related proteins: LRP1 and Megalin. LTP accumulates on specific neurons that connect to cells that produce Insulin-like peptides, and induces their release into the circulation. This increases systemic Insulin signaling and the rate of larval development on yeast-containing food compared with a plant-based food of similar nutritional content.
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Reviewing Editor
- Mani Ramaswami, Trinity College Dublin, Ireland
Version history
- Received: May 1, 2014
- Accepted: October 1, 2014
- Accepted Manuscript published: October 2, 2014 (version 1)
- Version of Record published: October 28, 2014 (version 2)
Copyright
© 2014, Brankatschk 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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