Negative regulation of FAR1 at the Start of the yeast cell cycle.
In budding yeast, a switch between the mutually exclusive pathways of cell cycle progression and conjugation is controlled at Start in late G1 phase. Mating pheromones promote conjugation by arresting cells in G1 phase before Start. Pheromone-induced cell cycle arrest requires a functional FAR1 gene. We have found that FAR1 transcription and protein accumulation are regulated independently during the cell cycle. FAR1 RNA and protein are highly expressed in early G1, but decline sharply at Start. Far1 is phosphorylated just before it disappears at Start, suggesting that modification may target Far1 for degradation. Although FAR1 mRNA levels rise again during late S or G2 phase, reaccumulation of Far1 protein to functional levels is restricted until after nuclear division.
Rockefeller University, New York, New York 10021.
J D
JD
McKinney
F
F
Chang
N
N
Heintz
F R
FR
Cross
D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D015153:Blotting, Western; D017489:CDC28 Protein Kinase, S cerevisiae / Q000502:physiology; D002453:Cell Cycle / Q000502:physiology*; D002455:Cell Division / Q000235:genetics; D003227:Conjugation, Genetic / Q000235:genetics*; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D005690:Galactose / Q000494:pharmacology; D015966:Gene Expression Regulation, Fungal; D015151:Immunoblotting; D008969:Molecular Sequence Data; D010766:Phosphorylation; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology; D012331:RNA, Fungal / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D012724:Sex Attractants / Q000502:physiology*; D014158:Transcription, Genetic / Q000502:physiology; D015003:Yeasts / Q000166:cytology / Q000235:genetics*
D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D012724:Sex Attractants; D017489:CDC28 Protein Kinase, S cerevisiae; C074532:Cln3-Cdc28 kinase complex, S cerevisiae; D005690:Galactose