title: Autophagy proteins play cytoprotective and cytocidal roles in leucine starvation-induced cell death in Saccharomyces cerevisiae.
abstract: Autophagy is essential for prolonging yeast survival during nutrient deprivation; however, this report shows that some autophagy proteins may also be accelerating population death in those conditions. While leucine starvation caused YCA1-mediated apoptosis characterized by increased annexin V staining, nitrogen deprivation triggered necrotic death characterized by increased propidium iodide uptake. Although a Δatg8 strain died faster than its parental strain during nitrogen starvation, this mutant died slower than its parent during leucine starvation. Conversely, a Δatg11 strain died slower than its parent during nitrogen starvation, but faster during leucine starvation. Curiously, although GFP-Atg8 complemented the Δatg8 mutation, this protein made ATG8 cells more sensitive to nitrogen starvation, and less sensitive to leucine starvation. These results were difficult to explain if autophagy only extended life but could be an indication that a second form of autophagy could concurrently facilitate either apoptotic or necrotic cell death.
authors.affiliation: Department of Plant, Soil, and Entomological Sciences and Program for Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID USA.
authors.forename: Slawomir A
authors.initials: SA
authors.lastname: Dziedzic
authors.forename: Allan B
authors.initials: AB
authors.lastname: Caplan
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000187:drug effects; D019610:Cytoprotection / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007930:Leucine / Q000172:deficiency* / Q000378:metabolism; D050296:Microbial Viability / Q000187:drug effects; D009154:Mutation / Q000235:genetics; D009584:Nitrogen / Q000172:deficiency / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D020123:Sirolimus / Q000494:pharmacology
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; D007930:Leucine; D009584:Nitrogen; D020123:Sirolimus