A systematic high-throughput screen of a yeast deletion collection for mutants defective in PHO5 regulation.
In response to phosphate limitation, Saccharomyces cerevisiae induces transcription of a set of genes important for survival. One of these genes is PHO5, which encodes a secreted acid phosphatase. A phosphate-responsive signal transduction pathway (the PHO pathway) mediates this response through three central components: a cyclin-dependent kinase (CDK), Pho85; a cyclin, Pho80; and a CDK inhibitor (CKI), Pho81. While signaling downstream of the Pho81/Pho80/Pho85 complex to PHO5 expression has been well characterized, little is known about factors acting upstream of these components. To identify missing factors involved in the PHO pathway, we carried out a high-throughput, quantitative enzymatic screen of a yeast deletion collection, searching for novel mutants defective in expression of PHO5. As a result of this study, we have identified at least nine genes that were previously not known to regulate PHO5 expression. The functional diversity of these genes suggests that the PHO pathway is networked with other important cellular signaling pathways. Among these genes, ADK1 and ADO1, encoding an adenylate kinase and an adenosine kinase, respectively, negatively regulate PHO5 expression and appear to function upstream of PHO81.
Huang
Sidong
S
Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, 94143-2240, USA.
O'Shea
Erin K
EK
D000135:Acid Phosphatase; D000248:Adenosine Kinase / Q000378:metabolism; D000263:Adenylate Kinase / Q000378:metabolism; D001331:Automation; D001426:Bacterial Proteins / Q000378:metabolism; D003470:Culture Media / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D016213:Cyclins / Q000378:metabolism; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005821:Genetic Techniques; D005838:Genotype; D008164:Luminescent Proteins / Q000378:metabolism; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D010710:Phosphates / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction; D013997:Time Factors
D001426:Bacterial Proteins; D003470:Culture Media; D016213:Cyclins; D008164:Luminescent Proteins; C066824:PHO80 protein, S cerevisiae; C081227:PHO81 protein, S cerevisiae; D010710:Phosphates; D012333:RNA, Messenger; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; C054562:yellow fluorescent protein, Bacteria; D000248:Adenosine Kinase; D018844:Cyclin-Dependent Kinases; C058605:PHO85 protein, S cerevisiae; D000263:Adenylate Kinase; D000135:Acid Phosphatase; C488916:PHO5 protein, S cerevisiae