Fig. 3. Gene-dosage-dependent suppressors of YMR1-13xmyc depletion. (A) GAL1-YMR1-13xmyc sjl2 sjl3 cells were grown overnight in YP dextrose medium to initiate depletion of Ymr1-myc and transformed with yEP352 high-copy-number S. cerevisiae genomic library plasmids (see Materials and Methods) and subsequently plated to selective media in the presence of dextrose. Colonies were picked 4 days later and re-streaked to selective media containing dextrose. Plates were incubated for 4 days at 26°C. A representative transformant for each unique SYD plasmid is shown. Isolates that also rescued ymr1^ts sjl2 sjl3 cells at 35°C are underlined and set in bold print (also refer to Table 2). (B) Osmotic support rescues the lethal phenotype of ymr1 sjl2^ts sjl3 cells at 38°C (upper panels). ymr1 sjl2^ts sjl3 cells were transformed with either pRS415-YMR1 or an empty vector. Transformants were grown under selection to log phase and tenfold serial dilutions were plated to selective plates with or without 1M sorbitol and the plates were incubated for 3 days at the indicated temperature. Osmotic support rescues the lethal phenotype of sjl2 sjl3 depleted of Ymr1 (lower panels). ymr1 sjl2 sjl3 cells carrying pGAL1-YMR1-myc were grown on galactose and then changed to media containing glucose to deplete Ymr1. Tenfold serial dilutions were plated to selective plates (+dextrose) with or without 1M sorbitol and the plates were incubated for 3 days.