Transcriptome profiling of budding yeast expressing a mutant form of the SUMO protease Ulp1

Eukaryotic cells can modulate cellular levels of SUMO conjugation by regulating enzymes involved in these processes. For example, budding yeast exhibit an overall elevation of SUMO conjugation in response to heat shock, at least partly by triggering the degradation of the major SUMO protease, Ulp1.

The effects of elevated sumoylation during heat shock, and whether they play a protective or adaptive role to the stress, remain unclear. Since a large number of transcription-related proteins are targets of sumoylation, one possibility is that increased sumoylation during heat shock facilitates the expression of heat shock genes by altering the properties of key transcription factors. To explore this, we analyzed the transcriptome of a yeast strain, ulp1-mt (ulp1-I615N), which expresses a mutant form of Ulp1 with reduced SUMO protease activity.