GRASPing the unconventional secretory machinery to bridge cellular stress signaling to the extracellular proteome.

Markus Plomann,Constantinos Demetriades,Julian Nüchel

doi:10.15698/cst2021.11.259

Abstract

Cellular adaptation to stress is a crucial homeostatic process for survival, metabolism, physiology, and disease. Cells respond to stress stimuli (e.g., nutrient starvation, growth factor deprivation, hypoxia, low energy, etc.) by changing the activity of signaling pathways, and interact with their environment by qualitatively and quantitatively modifying their intracellular, surface, and extracellular proteomes. How this delicate communication takes place is a hot topic in cell biological research, and has important implications for human disease.

Highlights

Part of the cellular response to stress is an evolutionarily conserved, poorly-understood process called unconventional protein secretion (UPS)
In our recent study (Nüchel et al, 2021), we identified UPS as a cellular function that is regulated by mTOR complex 1 (mTORC1), and showed that GRASP55 is a novel mTORC1 substrate, establishing GRASP55 as the first Golgi-based effector of mTORC1 and revealing a physiological role for mTORC1 at the Golgi
By artificially tethering GRASP55 at the Golgi surface, we showed that GRASP55 relocalization is a prerequisite for UPS induction upon stress

Summary

Introduction

Part of the cellular response to stress is an evolutionarily conserved, poorly-understood process called unconventional protein secretion (UPS). GRASPing the unconventional secretory machinery to bridge cellular stress signaling to the extracellular proteome

Results

Conclusion