Figure 4

Genetic interactions between the Bre1/H2B ubiquitylation and pre-RNA splicing pathways. (A) Synthetic genetic interactions of bre1Δ were derived from BioGRID, and its interactions with RNA processing mutants were selected and displayed using the Osprey network visualization system [47]. Colored lines connect bre1Δ to mutations in genes leading to synthetic interactions (either positive or negative). The red triangle indicates genes that function in pre-mRNA splicing. (B) Growth analysis of double mutant cells of lea1Δ htb-K123R and msl1Δ htb-K123R. Cells carrying a URA3 plasmid expressing wild type HTB1 were transformed with a HIS3 plasmid carrying HTB1 or htb-K123R. After selection, transformants were grown at 30°C in SC-histidine medium for 24 hours. Cells were then spotted in 10-fold serial dilution onto SC-histidine plates or SC-histidine plates containing 1 mg of 5-FOA/ml, and the plates were incubated at 30°C for 2-3 days. Cells that were unable to lose the wild type HTB1 gene failed to grow on 5-FOA.