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Macroautophagy (autophagy) is an evolutionarily conserved recycling and stress response mechanism. Active at basal levels in eukaryotes, autophagy is upregulated under stress providing cells with building blocks such as amino acids. A lysosome-integrated sensor system composed of RRAG GTPases and MTOR complex 1 (MTORC1) regulates lysosome biogenesis and autophagy in response to amino acid availability. Stress-mediated inhibition of MTORC1 results in the dephosphorylation and nuclear translocation of the TFE/ MITF family of transcriptional factors, and triggers an autophagy-and lysosomal-related gene transcription program. The role of family members TFEB and TFE3 have been studied in detail, but the importance of MITF proteins in autophagy regulation is not clear so far. Here we introduce for the first time a specific role for MITF in autophagy control that involves upregulation of MIR211. We show that, under stress conditions including starvation and MTOR inhibition, a MITF-MIR211 axis constitutes a novel feed-forward loop that controls autophagic activity in cells. Direct targeting of the MTORC2 component RICTOR by MIR211 led to the inhibition of the MTORC1 pathway, further stimulating MITF translocation to the nucleus and completing an autophagy amplification loop. In line with a ubiquitous function, MITF and MIR211 were co-expressed in all tested cell lines and human tissues, and the effects on autophagy were observed in a cell-type independent manner. Thus, our study provides direct evidence that MITF has rate-limiting and specific functions in autophagy regulation. Collectively, the MITF-MIR211 axis constitutes a novel and universal autophagy amplification system that sustains autophagic activity under stress conditions.

Sulcus vocalis is a common pathology in the population and can be observed at all ages. The accuracy of diagnosis seems to depend on the measurement of the sulcus depth and the histological characteristics. For this reason, tools and strategies should be established in living subjects for effective management of this challenging disorder.

Background Although the lung is seen as the main target organ affected by SARS-CoV-2, other organs are also damaged. Aim We aimed to determine the extrapulmonary findings of autopsies performed on cases with positive results with postmortem polymerase chain reaction test. Methods Pathological changes in extrapulmonary organs were examined with light microscopy. Results Heart, liver, spleen, kidney, pancreas, and central nervous system samples of these cases were evaluated. About 80% of the cases were men, and 20% were women. In the examination of heart, 28 of the cases had scar, 14 had acute myocardial infarction, 6 had acute and previous myocardial infarction findings, 2 had myocarditis, and 4 had interstitial mononuclear inflammatory cell infiltration. In the examination of the liver, portal inflammation was observed in 84 of the cases, steatosis in 54, centrilobular necrosis in 9, and capillary endotheliitis in the portal area in 7 of them. In the evaluation of the kidney, 37 cases had chronic pyelonephritis, 36 had tubular damage, 15 had tubulointerstitial necrosis, 16 had subcapsular microhemorrhage, 10 had capillary endothelitis, and 9 had a microvascular fibrin trombosis in their glomerular capillaries. In the central nervous system, 8 cases had infarction and liquefaction, 56 had perivascular petechial hemorrhage, 54 had acute hypoxic ischemic change, 3 had parenchymal microhemorrhage, and 52 had capillary endotheliitis. Conclusion Autopsies play an important role in systematically examining the damage caused by the virus in all organs in order to elucidate the pathogenesis of SARS-CoV-2 infection and contribute to the clinical management of infected patients.