Upstream open reading frames regulate the cell cycle-dependent expression of the RNA helicase Rok1 in Saccharomyces cerevisiae.
The RNA helicase Rok1 plays a role in rRNA processing and in control of cell cycle progression in Saccharomyces cerevisiae. We identified two upstream open reading frames (uORFs) within the ROK1 5' untranslated region, which inhibited Rok1 translation. Mutating uATG to uAAG or generation of a premature stop codon in the uORFs resulted in increased Rok1p levels. Rok1 protein levels oscillated during the cell cycle, declining at G1/S and increasing at G2. The uAAG1 mutation caused a constitutive level of Rok1 proteins throughout the cell cycle, resulting in significant delays in mitotic bud emergence and recovery from pheromone arrest. Our study reveals that the Rok1 protein level is regulated by uORFs, which is critical in cell cycle progression.
Jeon
Soonmee
S
Department of Microbiology and Molecular Biology, College of Biosciences and Biotechnology, Chungnam National University, Daejeon 305-764, Republic of Korea.
Kim
Jinmi
J
D020121:5' Untranslated Regions / Q000235:genetics; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics*; D053487:DEAD-box RNA Helicases / Q000235:genetics*; D016193:G1 Phase / Q000235:genetics; D015966:Gene Expression Regulation, Fungal / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames / Q000235:genetics*; D014176:Protein Biosynthesis / Q000235:genetics; D016196:S Phase / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000201:enzymology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*
D020121:5' Untranslated Regions; D029701:Saccharomyces cerevisiae Proteins; C120858:ROK1 protein, S cerevisiae; D053487:DEAD-box RNA Helicases