A genome-wide siRNA screen reveals multiple mTORC1 independent signaling pathways regulating autophagy under normal nutritional conditions.

ABSTRACT: Autophagy is a cellular catabolic mechanism that plays an essential function in protecting multicellular eukaryotes from neurodegeneration, cancer, and other diseases. However, we still know very little about mechanisms regulating autophagy under normal homeostatic conditions when nutrients are not limiting. In a genome-wide human siRNA screen, we demonstrate that under normal nutrient conditions upregulation of autophagy requires the type III PI3 kinase, but not inhibition of mTORC1, the essential negative regulator of starvation-induced autophagy. We show that a group of growth factors and cytokines inhibit the type III PI3 kinase through multiple pathways, including the MAPK-ERK1/2, Stat3, Akt/Foxo3, and CXCR4/GPCR, which are all known to positively regulate cell growth and proliferatio

SUBMITTER: Lipinski MM 

PROVIDER: S-EPMC2935848 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature