Sec24 phosphorylation regulates autophagosome abundance during nutrient deprivation
- University of California, San Diego, United States
- Columbia University, United States
- University of Pittsburgh School of Medicine, United States
Abstract
Endoplasmic Reticulum (ER)-derived COPII coated vesicles constitutively transport secretory cargo to the Golgi. However, during starvation-induced stress, COPII vesicles have been implicated as a membrane source for autophagosomes, distinct organelles that engulf cellular components for degradation by macroautophagy (hereafter called autophagy). How cells regulate core trafficking machinery to fulfill dramatically different cellular roles in response to environmental cues is unknown. Here we show that phosphorylation of conserved amino acids on the membrane-distal surface of the Saccharomyces cerevisiae COPII cargo adaptor, Sec24, reprograms COPII vesicles for autophagy. We also show casein kinase 1 (Hrr25) is a key kinase that phosphorylates this regulatory surface. During autophagy, Sec24 phosphorylation regulates autophagosome number and its interaction with the C-terminus of Atg9, a component of the autophagy machinery required for autophagosome initiation. We propose that the acute need to produce autophagosomes during starvation drives the interaction of Sec24 with Atg9 to increase autophagosome abundance.
Article and author information
Author details
Susan Ferro-Novick
Funding
National Institute of General Medical Sciences (GM114111)
- Saralin Davis
- Juan Wang
- Susan Ferro-Novick
National Cancer Institute (CA169186)
- Yu Jiang
National Institute of General Medical Sciences (GM085089)
- Kyle Stahmer
- Ramya Lakshminarayan
- Elizabeth A Miller
National Institute of General Medical Sciences (GM115422)
- Saralin Davis
- Juan Wang
- Susan Ferro-Novick
Medical Research Council (MC_UP_1201/10)
- Elizabeth A Miller
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Noboru Mizushima, The University of Tokyo, Japan
Version history
- Received: September 1, 2016
- Accepted: November 14, 2016
- Accepted Manuscript published: November 18, 2016 (version 1)
- Version of Record published: December 8, 2016 (version 2)
Copyright
© 2016, Davis 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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Sec24 phosphorylation regulates autophagosome abundance during nutrient deprivation
eLife 5:e21167.
https://doi.org/10.7554/eLife.21167
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