The Deubiquitinase USP9x is a New Player in autophagosome biogenesis and is involved in VMP1-dependent selective autophagy.

FELIPE RENNA; DANIEL GRASSO; VACCARO, MARÍA INÉS; TAMARA ORQUERA

CABA

Congreso; IV INTERNATIONAL CONGRESS IN TRANSLATIONAL MEDICINE; 2018

Universidad de Buenos Aires y Universidad Albert Ludwigs, Friburgo, Alemania

Intracellular activation of zymogen granules triggers pancreas self-digestion and leads to acute pancreatitis. Most of acute pancreatitis cases are self-limited, suggesting the importance of response mechanisms of acinar cells. VMP1 is an autophagy-related protein whose expression is essential for autophagosome biogenesis and its expression is induced by pancreatitis. VMP1 mediates zymophagy, a protective selective type of autophagy-mediated degradation of zymogen granules that prevents the spreading of activated enzymes within pancreas tissue. Previously we demonstrated that the deubiquitinase USP9x interacts with VMP1 during zymophagy in acute pancreatitis. The aim of this work is to elucidate the role of USP9x in autophagosome formation. By immunofluorescence, USP9x presents a cytoplasmic diffuse pattern at basal conditions, and it relocates after 15 min of starvation to a perinuclear area (48.0% ± 1.2 vs 40.5% ± 1.9 p