RESUMO
Genome-wide location analysis was used to determine how the yeast cell cycle gene expression program is regulated by each of the nine known cell cycle transcriptional activators. We found that cell cycle transcriptional activators that function during one stage of the cell cycle regulate transcriptional activators that function during the next stage. This serial regulation of transcriptional activators forms a connected regulatory network that is itself a cycle. Our results also reveal how the nine transcriptional regulators coordinately regulate global gene expression and diverse stage-specific functions to produce a continuous cycle of cellular events. This information forms the foundation for a complete map of the transcriptional regulatory network that controls the cell cycle.
Assuntos
Ciclo Celular/genética , Regulação Fúngica da Expressão Gênica , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Genoma FúngicoRESUMO
Understanding how DNA binding proteins control global gene expression and chromosomal maintenance requires knowledge of the chromosomal locations at which these proteins function in vivo. We developed a microarray method that reveals the genome-wide location of DNA-bound proteins and used this method to monitor binding of gene-specific transcription activators in yeast. A combination of location and expression profiles was used to identify genes whose expression is directly controlled by Gal4 and Ste12 as cells respond to changes in carbon source and mating pheromone, respectively. The results identify pathways that are coordinately regulated by each of the two activators and reveal previously unknown functions for Gal4 and Ste12. Genome-wide location analysis will facilitate investigation of gene regulatory networks, gene function, and genome maintenance.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Sítios de Ligação , Ciclo Celular , DNA Fúngico/genética , DNA Fúngico/metabolismo , Galactose/metabolismo , Genes Fúngicos , Fator de Acasalamento , Análise de Sequência com Séries de Oligonucleotídeos , Peptídeos/farmacologia , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Ativação TranscricionalRESUMO
The transcription factors TFIID and SAGA are multi-subunit complexes involved in transcription by RNA polymerase II. TFIID and SAGA contain common TATA-binding protein (TBP)-associated factor (TAF(II)) subunits and each complex contains a subunit with histone acetyltransferase activity. These observations have raised questions about whether the functions of the two complexes in vivo are unique or overlapping. Here we use genome-wide expression analysis to investigate how expression of the yeast genome depends on both shared and unique subunits of these two complexes. We find that expression of most genes requires one or more of the common TAF(II) subunits, indicating that the functions of TFIID and SAGA are widely required for gene expression. Among the subunits shared by TFIID and SAGA are three histone-like TAF(II)s, which have been proposed to form a sub-complex and mediate a common function in global transcription. Unexpectedly, we find that the histone-like TAF(II)s have distinct roles in expression of the yeast genome. Most importantly, we show that the histone acetylase components of TFIID and SAGA (TAF(II)145 and Gcn5) are functionally redundant, indicating that expression of a large fraction of yeast genes can be regulated through the action of either complex.
Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas Fúngicas/fisiologia , Proteínas Quinases/fisiologia , Proteínas de Saccharomyces cerevisiae , Fatores Associados à Proteína de Ligação a TATA , Fatores de Transcrição TFII/fisiologia , Fatores de Transcrição/fisiologia , Transcrição Gênica/fisiologia , Acetiltransferases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Histona Acetiltransferases , Substâncias Macromoleculares , Mutagênese , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Quinases/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiologia , Fator de Transcrição TFIID , Fatores de Transcrição/genética , Fatores de Transcrição TFII/genéticaRESUMO
Bacteriophage SPO1 gene 33 and 34 products are required for SPO1 late gene transcription. Both proteins bind to the core RNA polymerase of the Bacillus subtilis host to direct the recognition of SPO1 late gene promoters, whose sequences differ from those of SPO1 early and middle gene promoters. We have located and cloned the genes for these two regulatory proteins, and have engineered their expression in Escherichia coli by placing them under the control of the bacteriophage lambda PL promoter. Nucleotide sequence analysis indicated that genes 33 and 34 overlap by 4 base-pairs and encode highly charged, slightly basic proteins of molecular weight 11,902 and 23,677, respectively.
Assuntos
Bacteriófagos/genética , RNA Polimerases Dirigidas por DNA/genética , Genes Reguladores , Genes Virais , Sequência de Aminoácidos , Bacillus subtilis/genética , Sequência de Bases , Clonagem Molecular , DNA Viral , Escherichia coli/genética , Biossíntese de Proteínas , Transcrição Gênica , Proteínas ViraisRESUMO
Bacteriophage SPO1 gene 27, whose product is required for late gene transcription and DNA replication, has been cloned in Escherichia coli, and its complete nucleotide sequence has been determined. We infer that the product of gene 27 is a highly basic 17,518-dalton protein of 155 amino acids. The gene for this regulatory protein is transcribed from two promoters: an early promoter situated before the adjacent upstream gene 28 and a middle promoter located between genes 28 and 27.
Assuntos
Bacteriófagos/genética , Genes Reguladores , Genes Virais , Bacillus subtilis , Sequência de Bases , Clonagem Molecular , Replicação do DNA , Peso Molecular , Transcrição Gênica , Proteínas Virais/genética , Proteínas Virais/fisiologiaAssuntos
Bacillus subtilis/genética , Bacteriófagos/genética , DNA Viral , Transcrição Gênica , Bacteriófago lambda/genética , Sequência de Bases , Clonagem Molecular , RNA Polimerases Dirigidas por DNA/genética , Eletroforese em Gel de Ágar , Hibridização de Ácido Nucleico , Óperon , Pentoxil (Uracila)/análogos & derivados , Pentoxil (Uracila)/metabolismoRESUMO
A detailed restriction endonuclease map for the genome of Bacillus subtilis phage SP01 is presented. Sites of cleavage for the restriction enzymes BglII, EcoRI, HaeIII, and SalI were determined. This physical map showed that SP01 DNA was 140 kilobases in length and contained a repeated sequence of 12.4 kilobases at its termini. Combined with previously published information, we were also able to identify the general locations of genes expressed at early, middle, or late times in the phage lytic cycle. In particular, early genes were largely clustered in the terminal repeats, whereas a major cluster of late genes was located in the left-central portion of the genome.