title: Purification and characterization of a ubiquitin-like system for autophagosome formation.
abstract: Autophagy refers to the bulk degradation of cellular proteins and organelles through an autophagosome and plays a pivotal role in the development, cellular differentiation, aging, and elimination of aberrant structures. A failure of autophagy has been implicated in a growing list of mammalian disease states, including cancer and cardiomyopathy. Two ubiquitin-like systems are highly involved in autophagy, especially in the formation of autophagosomes. Here, we purified and characterized Atg7 (an E1-like enzyme), and Atg3 and Atg10 (E2-like enzymes) in order to gain an insight into the role played by ubiquitin-like systems in the formation of autophagosomes. Interestingly, we observed that Atg7 forms a homodimer to construct an active conformation, unlike other E1-like enzymes. Although Atg3 was detected as a monomer under physiological conditions, Atg10 existed in an oligomeric form, indicating that the mechanism by which Atg10 functions may differ from that of Atg3.
authors.affiliation: School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea.
authors.forename: Joo Young
authors.initials: JY
authors.lastname: Bae
authors.forename: Hyun Ho
authors.initials: HH
authors.lastname: Park
mesh_terms: D001343:Autophagy; D000071193:Autophagy-Related Protein 7; D000071183:Autophagy-Related Proteins; D010588:Phagosomes / Q000378:metabolism*; D055503:Protein Multimerization; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000302:isolation & purification / Q000378:metabolism*; D044763:Ubiquitin-Conjugating Enzymes / Q000302:isolation & purification / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: C114830:ATG7 protein, S cerevisiae; D000071183:Autophagy-Related Proteins; D029701:Saccharomyces cerevisiae Proteins; C557619:ATG10 protein, S cerevisiae; D044763:Ubiquitin-Conjugating Enzymes; D044767:Ubiquitin-Protein Ligases; D000071193:Autophagy-Related Protein 7; C104235:ATG3 protein, S cerevisiae