For galactose grown yeast cells chromatin immunoprecipitation(ChIp) with an antibody that pulls down the Gal4 protein A more complete view of galactose revealed some surprises. In addition to induced gene expression in 5. cerevisiae confirming that Gal4 binds to the promoters regions upstream of the expected Gal genes Images removed due to copyright reasons the Gal4 protein also binds to the promoter Please see Ren, Bing, et al. "Genome-wide regions of 4 other genes, namely Fur4, Pcl10, Location and Function of DNA Binding Proteins. Mth1 (shown in the adjacent figure)and Gcy1 Science290,no.5500Dec.22,2000)2306-9 (not shown). Note that these genes were shown to be induced by galactose in the previous section. Just how the up-regulation of Fur4, Pcl10 and Mth1 might contribute to optimizing the metabolism of galactose is shown in this figure, but the role gcy 1 plays is unclear. Clearly taking a global look at what genes are up-regulated in the presence of galactose, and taking a global look at what promoters are bound the Gal4 regulator, has clearly enriched our view of how S cerevisiae adapts the presence of this sugar. The ChIP approach, followed by hy bridization to DNa microarrays, was originally limited to monitoring binding of transcription nages removed due to copyright reasons. regulators for which there Please see Ren, Bing, et al. "Genome-wide were good precipitating Location and Function of DNA Binding Proteins antibodies However this Science290,no.5500(Dec.22,2000):23069 limitation was recently eliminated by fusing an sequences represent epitope TAG to each the upstream cis regulator gene. This acting regions of all epitope TAG is recognized 5. 800 genes by a strong antibody and so a single antibody can pull down gulatory Protein romoter binds Gene Promoter(immunoprecipitate)>100 different Muti-Component Loop gulatory protein h of which is expressed in its own yeast strain This has enabled a massive study to identify all of the target genes for Single Input Me each of 106 transcriptional regulators in S. cerevisiae growing in a defined medium a compilation of all the data has revealed a number of poea panin fundamentally different regulatory tifs these are shown in theFor galactose grown yeast cells chromatin immunoprecipitation (ChIP) with an antibody that pulls down the Gal4 protein revealed some surprises. In addition to confirming that Gal4 binds to the promoters regions upstream of the expected Gal genes, the Gal4 protein also binds to the promoter regions of 4 other genes, namely Fur4, Pcl10, Mth1 (shown in the adjacent figure) and Gcy1 (not shown). Note that these genes were shown to be induced by galactose in the previous section. Just how the up-regulation of Fur4, Pcl10 and Mth1 might contribute to optimizing the metabolism of galactose is shown in this figure, but the role Gcy1 plays is unclear. Clearly, taking a global look at what genes are up-regulated in the presence of galactose, and taking a global look at what promoters are bound by the Gal4 regulator, has clearly enriched our view of how S. cerevisiae adapts to the presence of this sugar. A more complete view of galactose induced gene expression in S. cerevisiae A more complete view of galactose induced gene expression in S. cerevisiae The ChIP approach, followed by hybridization to DNA microarrays, was originally limited to monitoring binding of transcriptional regulators for which there were good precipitating antibodies. However, this limitation was recently eliminated by fusing an epitope TAG to each regulator gene. This epitope TAG is recognized by a strong antibody, and so a single antibody can “pull down” (immunoprecipitate) >100 different regulatory proteins, each of which is expressed in its own yeast strain. Arrayed probe sequences represent the upstream cis￾acting regions of all 5,800 genes Arrayed probe sequences represent the upstream cis￾acting regions of all 5,800 genes Regulatory Protein Gene Promoter Regulatory Protein binds Gene Promoter Regulatory Protein Gene Promoter Regulatory Protein binds Gene Promoter This has enabled a massive study to identify all of the target genes for each of 106 transcriptional regulators in S. cerevisiae growing in a defined medium. A compilation of all the data has revealed a number of fundamentally different regulatory motifs; these are shown in the Images removed due to copyright reasons. Please see Ren, Bing, et. al. "Genome-wide Location and Function of DNA Binding Proteins." Science 290, no. 5500 (Dec. 22, 2000): 2306-9. Images removed due to copyright reasons. Please see Ren, Bing, et. al. "Genome-wide Location and Function of DNA Binding Proteins." Science 290, no. 5500 (Dec. 22, 2000): 2306-9