Dynamic Sumoylation of a Conserved Transcription Corepressor Prevents Persistent Inclusion Formation during Hyperosmotic Stress
Fig 5
Distinct alterations in transcription occur with the sumoylation-deficient Tup1 and Cyc8 mutants.
RNA was collected from biological duplicate samples of wild-type and mutant strains (expressing Tup1K270R and/or Cyc84KtoR from their endogenous promoters) that were exposed to 0, 30, or 60 minutes of hyperosmotic stress (1.2M sorbitol). Microarray experiments were performed in which the wild-type, unstressed replicate sample served as the reference for comparison with all other samples with a set of replicates. Log2-transformed gene expression ratios were averaged across replicate comparisons. (A) Hierarchical clustering of gene expression changes that are ≥1.57-fold at the 0 time point. Venn diagrams display overlap between mutant datasets. (B) Hierarchical clustering of mutant-effect ratios from gene expression changes that are ≥1.57-fold during 0, 30, and 60 minutes of hyperosmotic stress. Actual gene expressions changes are in S1H Fig. Venn diagrams display overlap between mutant datasets at 30 minutes. (C, D) Cyc84KtoR cells have a modest growth deficit in hyperosmotic stress. (C) 10-fold dilutions of the indicated strains were spotted on rich media with or without 1M NaCl. Asterisk indicates a Cyc84KtoR isolate that does not exhibit a growth defect. (D) Three independent cultures of the indicated strains were inoculated to an optical density of 0.01 measured by absorbance at 600nm in rich media with or without 1M NaCl. Absorbance values were measured every 5 minutes over the course of 48 hours in a Bioscreen C reader (Growth Curves USA). Curves are the averages of three independent cultures for each strain.