Overexpression of RAD5 and PCNA does not rescue the UV-radiation sensitivity phenotype of lsm1Δ. Logarithmically growing cultures transformed with plasmid expressing PCNA (panel A) or RAD5 (panel B) were plated on YPD plates, irradiated (80 J/m² for wild type and lsm1Δ, 10 J/m² for rad5Δ), and incubated in the dark to determine viability. Results are the mean values of two independent experiments, with bars indicating SEM