Atg3 Antibody

Autophagy is a catabolic process for the autophagosomic-lysosomal degradation of bulk cytoplasmic contents (1). The molecular machinery of autophagy was largely discovered in yeast and referred to as autophagy-related genes (Atg). Formation of the autophagic vesicles involves two ubiquitin-like conjugation systems, Atg12-Atg5 and Atg8-phosphatidylethanolamine (Atg8-PE), which are essential for autophagy and widely conserved in eukaryotes (2). There are at least three Atg8 homologs in mammalian cells, GATE-16, GABARAP, and LC3, that are conjugated by lipids (3,4). Lipid conjugation of Atg8 and its mammalian homologs requires Atg3 (Apg3p/Aut1p in yeast), an ubiquitously expressed E2-like enzyme (5-7). Following C-terminal cleavage by the cysteine protease Atg4, the exposed glycine residue of Atg8 binds to the E1-like enzyme Atg7, is transferred to Atg3, and then conjugated to phophatidylethanolamine. Atg3-deficient mice die within 1 day after birth and are completely defective for the conjugation of Atg8 homlogs and autophagome formation (8). 1.Reggiori, F. and Klionsky, D.J. (2002) Eukaryot Cell 1, 11-21. 2.Ohsumi, Y. (2001) Nat Rev Mol Cell Biol 2, 211-6. 3.Kabeya, Y. et al. (2000) EMBO J 19, 5720-8. 4.Kabeya, Y. et al. (2004) J Cell Sci 117, 2805-12. 5.Tanida, I. et al. (2002) J Biol Chem 277, 13739-44. 6.Ichimura, Y. et al. (2000) Nature 408, 488-92. 7.Schlumpberger, M. et al. (1997) J Bacteriol 179, 1068-76. 8.Sou, Y.S. et al. (2008) Mol Biol Cell 19, 4762-75.