title: Generation of cell lines with tetracycline-regulated autophagy and a role for autophagy in controlling cell size.
abstract: Autophagy is an intracellular bulk degradation system. We established mouse fibroblast lines coupling the Tet-off system with an Atg5(-/-) mouse embryonic fibroblast line to artificially regulate autophagic ability. In the presence of doxycycline (Dox), Atg5 expression was completely suppressed and these cells were autophagy-defective. After removal of Dox, autophagic ability was restored within 6h. Very low levels of Atg5 could induce an autophagy competent state. We applied this novel system to examine the contribution of autophagy to controlling cell size. Cell size reduction in response to starvation was significantly inhibited in cells unable to undergo autophagy. The generated cell lines will be useful reagents for future mechanistic studies into the regulation and physiologic significance of autophagy.
authors.affiliation: Department of Bioregulation and Metabolism, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Tokyo 113-8613, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Hosokawa
authors.forename: Yukichi
authors.initials: Y
authors.lastname: Hara
authors.forename: Noboru
authors.initials: N
authors.lastname: Mizushima
mesh_terms: D000818:Animals; D001343:Autophagy / Q000187:drug effects* / Q000502:physiology*; D000071187:Autophagy-Related Protein 5; D002460:Cell Line; D048429:Cell Size; D004318:Doxycycline / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D017930:Genes, Reporter / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D013752:Tetracycline / Q000494:pharmacology*; D013997:Time Factors
chemical_list: C495773:Atg5 protein, mouse; D000071187:Autophagy-Related Protein 5; D008869:Microtubule-Associated Proteins; D013752:Tetracycline; D004318:Doxycycline