The Ubi brothers reunited.
Atg12 and Atg8/LC3 are two ubiquitin-like proteins involved in autophagosome formation. They show several similar characteristics just like brothers evolved from the same ancestor, however, their functional relationship has been obscure. We recently reported that a super protein complex, the Atg16L complex, which consists of multiple Atg12-Atg5 conjugates and the associating protein Atg16L, has an E3-like role in the LC3 lipidation reaction(1). The activated intermediate, LC3-Atg3 (E2) is recruited to the site where the lipidation takes place by virtue of the Atg16L complex. Thus, these two closely resembling systems are connected also in terms of their functions. This finding will provide further important clues as to the origin of the autophagosome membrane, and how the process is regulated by starvation and PtdIns3P signals.
Noda
Takeshi
T
Department of Cellular Regulation, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.
Fujita
Naonobu
N
Yoshimori
Tamotsu
T
D000818:Animals; D001343:Autophagy / Q000502:physiology*; D000071192:Autophagy-Related Protein 12; D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D046912:Multiprotein Complexes / Q000378:metabolism; D010588:Phagosomes / Q000378:metabolism / Q000648:ultrastructure; D015398:Signal Transduction / Q000502:physiology; D025841:Small Ubiquitin-Related Modifier Proteins / Q000235:genetics / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism*
C466624:ATG12 protein, human; C518959:ATG16L1 protein, human; D000071192:Autophagy-Related Protein 12; D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins; C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D046912:Multiprotein Complexes; D025841:Small Ubiquitin-Related Modifier Proteins; D025801:Ubiquitin