A stress assembly that confers cell viability by preserving ERES components during amino-acid starvation.
Nutritional restriction leads to protein translation attenuation that results in the storage and degradation of free mRNAs in cytoplasmic assemblies. In this study, we show in Drosophila S2 cells that amino-acid starvation also leads to the inhibition of another major anabolic pathway, the protein transport through the secretory pathway, and to the formation of a novel reversible non-membrane bound stress assembly, the Sec body that incorporates components of the ER exit sites. Sec body formation does not depend on membrane traffic in the early secretory pathway, yet requires both Sec23 and Sec24AB. Sec bodies have liquid droplet-like properties, and they act as a protective reservoir for ERES components to rebuild a functional secretory pathway after re-addition of amino-acids acting as a part of a survival mechanism. Taken together, we propose that the formation of these structures is a novel stress response mechanism to provide cell viability during and after nutrient stress.
Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
Margarita
M
Zacharogianni
Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
Angelica
A
Aguilera-Gomez
Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
Tineke
T
Veenendaal
Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
Jan
J
Smout
Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
Catherine
C
Rabouille
D000596:Amino Acids / Q000172:deficiency*; D000818:Animals; D001692:Biological Transport; D022181:COP-Coated Vesicles / Q000378:metabolism; D002470:Cell Survival; D020755:Coat Protein Complex I / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology* / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D036681:Fluorescence Recovery After Photobleaching; D055571:Secretory Pathway; D022142:Secretory Vesicles / Q000378:metabolism / Q000648:ultrastructure; D013312:Stress, Physiological; D059008:Time-Lapse Imaging
D000596:Amino Acids; D020755:Coat Protein Complex I; D029721:Drosophila Proteins
COPII; D. melanogaster; ER exit sites; amino-acid starvation; cell biology; liquid droplets; protein transport through the secretory pathway; stress granules