ATPase activity of DFCP1 controls selective autophagy

Abstract

Cellular homeostasis is governed by removal of damaged organelles and protein aggregates by selective autophagy mediated by cargo adaptors such as p62/SQSTM1. Autophagosomes can assemble in specialized cup-shaped regions of the endoplasmic reticulum (ER) known as omegasomes, which are characterized by the presence of the ER protein DFCP1/ZFYVE1. The function of DFCP1 is unknown, as are the mechanisms of omegasome formation and constriction. Here, we demonstrate that DFCP1 is an ATPase that is activated by membrane binding and dimerizes in an ATP-dependent fashion. Whereas depletion of DFCP1 has a minor effect on bulk autophagic flux, DFCP1 is required to maintain the autophagic flux of p62 under both fed and starved conditions, and this is dependent on its ability to bind and hydrolyse ATP. While DFCP1 mutants defective in ATP binding or hydrolysis localize to forming omegasomes, these omegasomes fail to constrict properly in a size-dependent manner. Consequently, the release of nascent autophagosomes from large omegasomes is markedly delayed. While knockout of DFCP1 does not affect bulk autophagy, it inhibits selective autophagy, including aggrephagy, mitophagy and micronucleophagy. We conclude that DFCP1 mediates ATPase-driven constriction of large omegasomes to release autophagosomes for selective autophagy.

Contrasting views on the role of AMPK in autophagy

“…[77] A recent study has shown that DFCP1 (Double FYVE-Containing Protein 1), a protein involved in forming initial membrane structures for autophagosomes, [78,79] possesses ATPase activity. [80] The need for energy in autophagy is further supported by recent research demonstrating that functional mitochondria are necessary for autophagy induction [22,81] or for maximizing autophagy. [82] This emphasizes the crucial role of mitochondria in facilitating autophagy initiation.…”

Mechanism and role of mitophagy in the development of severe infection

“…The PI3P-positive area of the ER, known as the omegasome, is the origin of the phagophore [ 28 ]. PI3P then recruits downstream effector proteins such as double FYVE-domain containing protein 1, WD repeats domain phosphoinositide interacting (WIPI) protein, and soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) [ 29 , 30 ].…”

Friends and Foes: The Ambivalent Role of Autophagy in HIV-1 Infection

“…The active ULK1 complex in turn stimulates the Class III phosphatidylinositol 3-kinase (PI3KC3) complex I, comprised of Beclin-1, ATG14, the kinase Vacuolar protein sorting (Vps) 34 and membrane-anchoring Vps15 [ 9 ]. The activity of this complex results in a locally elevated production of Phosphatidylinositol 3-phosphate (PI3P), which in turn recruits WD-repeat protein interacting with phosphoinositides (WIPI) proteins and Double FYVE-containing protein 1 (DFCP1), which is required especially for selective autophagy [ 10 , 11 ]. Next, a double-layer membrane, the so-called phagophore, is assembled in an ATG9-dependent manner with lipids mainly derived from the endoplasmic reticulum (ER) [ 12 , 13 ].…”

“…Viruses 2024, 16, 500 2 of 18 proteins and Double FYVE-containing protein 1 (DFCP1), which is required especially for selective autophagy [10,11]. Next, a double-layer membrane, the so-called phagophore, is assembled in an ATG9-dependent manner with lipids mainly derived from the endoplasmic reticulum (ER) [12,13].…”