Macroautophagy is essential for the maintenance of cellular homeostasis and physiology in mammals, and relies on vesicle fusion between the autophagosome and the lysosome, forming the autolysosome to degrade unwanted cytosolic contents for recycling. ATP13A2 deficiency impaired autophagosome–lysosome fusion in cultured cells and in in vitro reconstitution assays. During autophagosome formation a branched actin network shapes the developing omegasome and phagopore . An autophagosome is a spherical structure with double layer membranes. Introduction. A portion of cytoplasm, including organelles, is enclosed by a phagophore or isolation membrane to form an autophagosome. Additionally, actin comet tail motility promotes formation of the autophagosome from the phagopore [77,81]. The outer membrane of the autophagosome subsequently fuses with the endosome and then the lysosome, and the internal material is degraded. The cargo-laden autophagosome then gets transported to and fuses with the lysosome or the late endosome, where the content of the autophagosome is … Varicella-zoster virus inhibits autophagosome-lysosome fusion and the degradation stage of mTOR-mediated autophagic flux. Autophagy is a key mechanism for clearing pathogens, and many bacteria and viruses have evolved strategies for interfering with the formation or maturation of autophagosomes in host cells. Autophagosome accumulation and autophagosome–lysosome interaction were investigated in CaLu-1/GFP-LC3 shLuc and shATP6V0A1 cells by confocal microscopy. Furthermore, autophagosomes can fuse with endosomes to create intermediary … … Misfolded proteins and organelles such as damaged mitochondria and cytosolic lipid droplets are engulfed by a double membrane autophagosome, and then delivered to a lysosome for degradation (Yang and Klionsky, 2010).The dysfunction of autophagy is associated with many human diseases such as cancer, … Autophagy is a highly conserved cellular degradation pathway. As shown in Figure 7A , endogenous and 0.3 µM GMI-induced autophagosomes fused with lysosomes; 1.2 µM GMI induced autophagosomes partly fused with lysosomes ( Figure 7A ). Here, we investigated the role of Arl8B, an adaptor molecule between lysosomes and kinesins. The membrane fusion between the autophagosome and lysosome requires ATG8 family proteins and autophagy-related SNARE proteins … Author information: (1)Department of Pediatrics, Section of Infectious Diseases, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, United States. It is the key structure in macroautophagy, the intracellular degradation system for cytoplasmic contents (e.g., abnormal intracellular proteins, excess or damaged organelles, invading microorganisms).After formation, autophagosomes deliver cytoplasmic components to the lysosomes. In ATP13A2-deficient cells or Drosophila melanogaster or mouse tissues, lysosomal localization and activity of HDAC6 were reduced, with increased acetylation of tubulin and cortactin. SARS-CoV-2 ORF3a prevents autophagosome-lysosome fusion. Rab7, SNARE proteins, ATG14 and ATG6 also play roles in autophagosome-lysosome fusion, with the latter also participating to some extent in endosomal membrane trafficking [118,126,127]. Normal actin cytoskeletal dynamics have been specifically implicated in autophagosome-lysosome fusion during selective autophagy . 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