Regulation of autophagy by miRNAs

Official URL: http://www.sciencedirect.com/science/article/pii/B9780124055308000133

To cope with stress factors including nutrient deprivation, toxins, abnormal protein accumulation, cells developed mechanisms to repair damage caused by stress or, in cases where the damage is irrepairable, cell death responses. Autophagy and apoptosis are among the most important stress and death response mechanisms. Autophagy is defined by sequestration and transport of cytoplasm pieces and organelles by double- or multi-membrane vesicles and, degradation of the cargo following fusion with lysosomes. Consequently, autophagy plays an important role in elimination of long-lived proteins, damaged organelles, mutant proteins and even intracellular bacteria and viruses, helping to survive stressfull conditions. Paradoxically, depending stress and cell type, autophagy may kill cells by a non-apoptotic programmed cell death mechanism called “autophagic cell death”. Recent studies including our publications suggest that miRNAs add a novel layer of regulation to autophagy pathways. Molecular details of autophagy regulation by miRNAs started to emerge in the last 2 years. In this chapter we will summarize acccumulating data on this novel mechanism of autophagy regulation.