GLA and profiling of proteasome, Spt23 and Mga2

The proteasome can regulate transcription through proteolytic processing of transcription factors and via gene locus binding, but few targets of proteasomal regulation have been identified. Using genome-wide location analysis and transcriptional profiling in Saccharomyces cerevisiae, we have established which genes are bound and regulated by the proteasome, and by Spt23 and Mga2, transcription factors activated by the proteasome. We observed proteasome association with gene sets that are highly transcribed, controlled by the mating-type loci, and involved in lipid metabolism. At ribosomal protein genes, proteasome and RNA polymerase II binding was enriched in a proteasome mutant, indicating a role for the proteasome in dissociating elongation complexes. The genomic occupancies of Spt23 and Mga2 overlapped significantly with the genes bound by the proteasome. Finally, the proteasome acts in two distinct ways, one dependent and one independent of Spt23/Mga2 cleavage, providing evidence for cooperative gene regulation by the proteasome and its substrates. Keywords: ChIP-chip; genetic modification transcriptional profiling Six genomic localization analysis (GLA, ChIP2) experiments are represented by 18 samples. Six transcriptional profiling experiments (prof) are also represented. Experiments were generally done in triplicate, with fluors swapped on the third replicate.