UBAC2 serves as a reticulophagy receptor to suppress inflammatory responses.

Abstract

Reticulophagy selectively degrades fragments of the endoplasmic reticulum (ER) through macroautophagy/autophagy to maintain ER homeostasis. The deficiency of reticulophagy results in the unfolded protein response (UPR), which is a crucial clue to the pathogenesis of inflammatory diseases. However, the detailed mechanism underlying the cross-regulation between reticulophagy and inflammatory diseases remains largely unclear. Recently, we have revealed that UBAC2 (UBA domain containing 2) is essential for controlling ER homeostasis as a novel reticulophagy receptor. MARK2 catalyzes the phosphorylation of UBAC2 at serine (S) 223, hence facilitating the progression of reticulophagy and inhibiting ER stress-induced inflammatory responses.