<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sha, Kai</style></author><author><style face="normal" font="default" size="100%">Choi, Seung-Hoon</style></author><author><style face="normal" font="default" size="100%">Im, Jeongdae</style></author><author><style face="normal" font="default" size="100%">Lee, Gyunghee G</style></author><author><style face="normal" font="default" size="100%">Loeffler, Frank</style></author><author><style face="normal" font="default" size="100%">Park, Jae H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regulation of ethanol-related behavior and ethanol metabolism by the Corazonin neurons and Corazonin receptor in Drosophila melanogaster.</style></title><secondary-title><style face="normal" font="default" size="100%">PLoS One</style></secondary-title><alt-title><style face="normal" font="default" size="100%">PLoS ONE</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Acetaldehyde</style></keyword><keyword><style  face="normal" font="default" size="100%">Alcohol Dehydrogenase</style></keyword><keyword><style  face="normal" font="default" size="100%">Aldehyde Dehydrogenase</style></keyword><keyword><style  face="normal" font="default" size="100%">Alleles</style></keyword><keyword><style  face="normal" font="default" size="100%">Animals</style></keyword><keyword><style  face="normal" font="default" size="100%">Cyclic AMP-Dependent Protein Kinases</style></keyword><keyword><style  face="normal" font="default" size="100%">Drosophila melanogaster</style></keyword><keyword><style  face="normal" font="default" size="100%">Drosophila Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Ethanol</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Male</style></keyword><keyword><style  face="normal" font="default" size="100%">Mutation</style></keyword><keyword><style  face="normal" font="default" size="100%">Neurons</style></keyword><keyword><style  face="normal" font="default" size="100%">Neuropeptides</style></keyword><keyword><style  face="normal" font="default" size="100%">Phenotype</style></keyword><keyword><style  face="normal" font="default" size="100%">Receptors, Neuropeptide</style></keyword><keyword><style  face="normal" font="default" size="100%">RNA, Messenger</style></keyword><keyword><style  face="normal" font="default" size="100%">Transcription, Genetic</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2014</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">e87062</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Impaired ethanol metabolism can lead to various alcohol-related health problems. Key enzymes in ethanol metabolism are alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH); however, neuroendocrine pathways that regulate the activities of these enzymes are largely unexplored. Here we identified a neuroendocrine system involving Corazonin (Crz) neuropeptide and its receptor (CrzR) as important physiological regulators of ethanol metabolism in Drosophila. Crz-cell deficient (Crz-CD) flies displayed significantly delayed recovery from ethanol-induced sedation that we refer to as hangover-like phenotype. Newly generated mutant lacking Crz Receptor (CrzR(01) ) and CrzR-knockdown flies showed even more severe hangover-like phenotype, which is causally associated with fast accumulation of acetaldehyde in the CrzR(01) mutant following ethanol exposure. Higher levels of acetaldehyde are likely due to 30% reduced ALDH activity in the mutants. Moreover, increased ADH activity was found in the CrzR(01) mutant, but not in the Crz-CD flies. Quantitative RT-PCR revealed transcriptional upregulation of Adh gene in the CrzR(01) . Transgenic inhibition of cyclic AMP-dependent protein kinase (PKA) also results in significantly increased ADH activity and Adh mRNA levels, indicating PKA-dependent transcriptional regulation of Adh by CrzR. Furthermore, inhibition of PKA or cAMP response element binding protein (CREB) in CrzR cells leads to comparable hangover-like phenotype to the CrzR(01) mutant. These findings suggest that CrzR-associated signaling pathway is critical for ethanol detoxification via Crz-dependent regulation of ALDH activity and Crz-independent transcriptional regulation of ADH. Our study provides new insights into the neuroendocrine-associated ethanol-related behavior and metabolism.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/24489834?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Griffith, Kevin L</style></author><author><style face="normal" font="default" size="100%">Fitzpatrick, M Megan</style></author><author><style face="normal" font="default" size="100%">Keen, Edward F</style></author><author><style face="normal" font="default" size="100%">Wolf, Richard E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Two functions of the C-terminal domain of Escherichia coli Rob: mediating &quot;sequestration-dispersal&quot; as a novel off-on switch for regulating Rob's activity as a transcription activator and preventing degradation of Rob by Lon protease.</style></title><secondary-title><style face="normal" font="default" size="100%">J Mol Biol</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Mol. Biol.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Decanoic Acids</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA-Binding Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Escherichia coli</style></keyword><keyword><style  face="normal" font="default" size="100%">Escherichia coli Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Gene Expression Regulation, Bacterial</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Microscopy, Fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">Models, Biological</style></keyword><keyword><style  face="normal" font="default" size="100%">Protease La</style></keyword><keyword><style  face="normal" font="default" size="100%">Protein Structure, Tertiary</style></keyword><keyword><style  face="normal" font="default" size="100%">Pyridines</style></keyword><keyword><style  face="normal" font="default" size="100%">Recombinant Fusion Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Trans-Activators</style></keyword><keyword><style  face="normal" font="default" size="100%">Transcription, Genetic</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May 8</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">388</style></volume><pages><style face="normal" font="default" size="100%">415-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In Escherichia coli, Rob activates transcription of the SoxRS/MarA/Rob regulon. Previous work revealed that Rob resides in three to four immunostainable foci, that dipyridyl and bile salts are inducers of its activity, and that inducers bind to Rob's C-terminal domain (CTD). We propose that sequestration inactivates Rob by blocking its access to the transcriptional machinery and that inducers activate Rob by mediating its dispersal, allowing interaction with RNA polymerase. To test &quot;sequestration-dispersal&quot; as a new mechanism for regulating the activity of transcriptional activators, we fused Rob's CTD to SoxS and used indirect immunofluorescence microscopy to determine the effect of inducers on SoxS-Rob's cellular localization. Unlike native SoxS, which is uniformly distributed throughout the cell, SoxS-Rob is sequestered without an inducer, but is rapidly dispersed when cells are treated with an inducer. In this manner, Rob's CTD serves as an anti-sigma factor in regulating the co-sigma-factor-like activity of SoxS when fused to it. Rob's CTD also protects its N-terminus from Lon protease, since Lon's normally rapid degradation of SoxS is blocked in the chimera. Accordingly, Rob's CTD has novel regulatory properties that can be bestowed on another E. coli protein.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19289129?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hancock, Leandria C</style></author><author><style face="normal" font="default" size="100%">Behta, Ryan P</style></author><author><style face="normal" font="default" size="100%">Lopes, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genomic analysis of the Opi- phenotype.</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Gene Expression Regulation, Fungal</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Fungal</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Genome, Fungal</style></keyword><keyword><style  face="normal" font="default" size="100%">Genomics</style></keyword><keyword><style  face="normal" font="default" size="100%">Inositol</style></keyword><keyword><style  face="normal" font="default" size="100%">Lac Operon</style></keyword><keyword><style  face="normal" font="default" size="100%">Models, Biological</style></keyword><keyword><style  face="normal" font="default" size="100%">Mutation</style></keyword><keyword><style  face="normal" font="default" size="100%">Phenotype</style></keyword><keyword><style  face="normal" font="default" size="100%">Phospholipids</style></keyword><keyword><style  face="normal" font="default" size="100%">Protein Folding</style></keyword><keyword><style  face="normal" font="default" size="100%">Repressor Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae Proteins</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">621-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Most of the phospholipid biosynthetic genes of Saccharomyces cerevisiae are coordinately regulated in response to inositol and choline. Inositol affects the intracellular levels of phosphatidic acid (PA). Opi1p is a repressor of the phospholipid biosynthetic genes and specifically binds PA in the endoplasmic reticulum. In the presence of inositol, PA levels decrease, releasing Opi1p into the nucleus where it represses transcription. The opi1 mutant overproduces and excretes inositol into the growth medium in the absence of inositol and choline (Opi(-) phenotype). To better understand the mechanism of Opi1p repression, the viable yeast deletion set was screened to identify Opi(-) mutants. In total, 89 Opi(-) mutants were identified, of which 7 were previously known to have the Opi(-) phenotype. The Opi(-) mutant collection included genes with roles in phospholipid biosynthesis, transcription, protein processing/synthesis, and protein trafficking. Included in this set were all nonessential components of the NuA4 HAT complex and six proteins in the Rpd3p-Sin3p HDAC complex. It has previously been shown that defects in phosphatidylcholine synthesis (cho2 and opi3) yield the Opi(-) phenotype because of a buildup of PA. However, in this case the Opi(-) phenotype is conditional because PA can be shuttled through a salvage pathway (Kennedy pathway) by adding choline to the growth medium. Seven new mutants present in the Opi(-) collection (fun26, kex1, nup84, tps1, mrpl38, mrpl49, and opi10/yol032w) were also suppressed by choline, suggesting that these affect PC synthesis. Regulation in response to inositol is also coordinated with the unfolded protein response (UPR). Consistent with this, several Opi(-) mutants were found to affect the UPR (yhi9, ede1, and vps74).</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16582425?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">McCool, Jesse D</style></author><author><style face="normal" font="default" size="100%">Long, Edward</style></author><author><style face="normal" font="default" size="100%">Petrosino, Joseph F</style></author><author><style face="normal" font="default" size="100%">Sandler, Hilary A</style></author><author><style face="normal" font="default" size="100%">Rosenberg, Susan M</style></author><author><style face="normal" font="default" size="100%">Sandler, Steven J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Measurement of SOS expression in individual Escherichia coli K-12 cells using fluorescence microscopy.</style></title><secondary-title><style face="normal" font="default" size="100%">Mol Microbiol</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Microbiol.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Adenosine Triphosphatases</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA Damage</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA Helicases</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA Repair</style></keyword><keyword><style  face="normal" font="default" size="100%">Escherichia coli K12</style></keyword><keyword><style  face="normal" font="default" size="100%">Escherichia coli Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Gene Expression Regulation, Bacterial</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Microscopy, Fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">Models, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Promoter Regions, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Recombinant Fusion Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">SOS Response (Genetics)</style></keyword><keyword><style  face="normal" font="default" size="100%">Ultraviolet Rays</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2004</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2004 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">53</style></volume><pages><style face="normal" font="default" size="100%">1343-57</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Many recombination, DNA repair and DNA replication mutants have high basal levels of SOS expression as determined by a sulAp-lacZ reporter gene system on a population of cells. Two opposing models to explain how the SOS expression is distributed in these cells are: (i) the 'Uniform Expression Model (UEM)' where expression is evenly distributed in all cells or (ii) the 'Two Population Model (TPM)' where some cells are highly induced while others are not at all. To distinguish between these two models, a method to quantify SOS expression in individual bacterial cells was developed by fusing an SOS promoter (sulAp) to the green fluorescent protein (gfp) reporter gene and inserting it at attlambda on the Escherichia coli chromosome. It is shown that the fluorescence in sulAp-gfp cells is regulated by RecA and LexA. This system was then used to distinguish between the two models for several mutants. The patterns displayed by priA, dnaT, recG, uvrD, dam, ftsK, rnhA, polA and xerC mutants were explained best by the TPM while only lexA (def), lexA3 (ind-) and recA defective mutants were explained best by the UEM. These results are discussed in a context of how the processes of DNA replication and recombination may affect cells in a population differentially.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/15387814?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gardocki, Mary Elizabeth</style></author><author><style face="normal" font="default" size="100%">Lopes, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression of the yeast PIS1 gene requires multiple regulatory elements including a Rox1p binding site.</style></title><secondary-title><style face="normal" font="default" size="100%">J Biol Chem</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Anoxia</style></keyword><keyword><style  face="normal" font="default" size="100%">Base Sequence</style></keyword><keyword><style  face="normal" font="default" size="100%">Binding Sites</style></keyword><keyword><style  face="normal" font="default" size="100%">Carbon</style></keyword><keyword><style  face="normal" font="default" size="100%">Chloramphenicol O-Acetyltransferase</style></keyword><keyword><style  face="normal" font="default" size="100%">Choline</style></keyword><keyword><style  face="normal" font="default" size="100%">Chromatography, Thin Layer</style></keyword><keyword><style  face="normal" font="default" size="100%">Conserved Sequence</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA, Complementary</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA-Binding Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Gene Deletion</style></keyword><keyword><style  face="normal" font="default" size="100%">Gene Expression Regulation, Fungal</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Inositol</style></keyword><keyword><style  face="normal" font="default" size="100%">Lipid Metabolism</style></keyword><keyword><style  face="normal" font="default" size="100%">Models, Biological</style></keyword><keyword><style  face="normal" font="default" size="100%">Models, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Molecular Sequence Data</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxygen</style></keyword><keyword><style  face="normal" font="default" size="100%">Phospholipids</style></keyword><keyword><style  face="normal" font="default" size="100%">Plasmids</style></keyword><keyword><style  face="normal" font="default" size="100%">Promoter Regions, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Protein Binding</style></keyword><keyword><style  face="normal" font="default" size="100%">Repressor Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">RNA</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Transcription, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Transferases (Other Substituted Phosphate Groups)</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2003 Oct 3</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">278</style></volume><pages><style face="normal" font="default" size="100%">38646-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The PIS1 gene is required for de novo synthesis of phosphatidylinositol (PI), an essential phospholipid in Saccharomyces cerevisiae. PIS1 gene expression is unusual because it is uncoupled from the other phospholipid biosynthetic genes, which are regulated in response to inositol and choline. Relatively little is known about regulation of transcription of the PIS1 gene. We reported previously that PIS1 transcription is sensitive to carbon source. To further our understanding of the regulation of PIS1 transcription, we carried out a promoter deletion analysis that identified three regions required for PIS1 gene expression (upstream activating sequence (UAS) elements 1-3). Deletion of either UAS1 or UAS2 resulted in an approximately 45% reduction in expression, whereas removal of UAS3 yielded an 84% decrease in expression. A comparison of promoters among several Saccharomyces species shows that these sequences are highly conserved. Curiously, the UAS3 element region (-149 to -138) includes a Rox1p binding site. Rox1p is a repressor of hypoxic genes under aerobic growth conditions. Consistent with this, we have found that expression of a PIS1-cat reporter was repressed under aerobic conditions, and this repression was dependent on both Rox1p and its binding site. Furthermore, PI levels were elevated under anaerobic conditions. This is the first evidence that PI levels are affected by regulation of PIS1 transcription.</style></abstract><issue><style face="normal" font="default" size="100%">40</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/12890676?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kaadige, Mohan R</style></author><author><style face="normal" font="default" size="100%">Lopes, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Opi1p, Ume6p and Sin3p control expression from the promoter of the INO2 regulatory gene via a novel regulatory cascade.</style></title><secondary-title><style face="normal" font="default" size="100%">Mol Microbiol</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Microbiol.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Basic Helix-Loop-Helix Transcription Factors</style></keyword><keyword><style  face="normal" font="default" size="100%">DNA-Binding Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Fungal Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Gene Expression Regulation, Fungal</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Regulator</style></keyword><keyword><style  face="normal" font="default" size="100%">Genes, Reporter</style></keyword><keyword><style  face="normal" font="default" size="100%">Genetic Complementation Test</style></keyword><keyword><style  face="normal" font="default" size="100%">Histone Deacetylases</style></keyword><keyword><style  face="normal" font="default" size="100%">Methyltransferases</style></keyword><keyword><style  face="normal" font="default" size="100%">Phenotype</style></keyword><keyword><style  face="normal" font="default" size="100%">Phospholipids</style></keyword><keyword><style  face="normal" font="default" size="100%">Promoter Regions, Genetic</style></keyword><keyword><style  face="normal" font="default" size="100%">Repressor Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae</style></keyword><keyword><style  face="normal" font="default" size="100%">Saccharomyces cerevisiae Proteins</style></keyword><keyword><style  face="normal" font="default" size="100%">Transcription Factors</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2003 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">823-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The INO2 gene of Saccharomyces cerevisiae is required for expression of most of the phospholipid biosynthetic genes. INO2 expression is regulated by a complex cascade that includes autoregulation, Opi1p-mediated repression and Ume6p-mediated activation. To screen for mutants with altered INO2 expression directly, we constructed an INO2-HIS3 reporter that provides a plate assay for INO2 promoter activity. This reporter was used to isolate mutants (dim1) that fail to repress expression of the INO2 gene in an otherwise wild-type strain. The dim1 mutants contain mutations in the OPI1 gene. To define further the mechanism for Ume6p regulation of INO2 expression, we isolated suppressors (rum1, 2, 3) of the ume6Delta mutation that overexpress the INO2-HIS3 gene. Two of the rum mutant groups contain mutations in the OPI1 and SIN3 genes showing that opi1 and sin3 mutations are epistatic to the ume6Delta mutation. These results are surprising given that Ume6p, Sin3p and Rpd3p are known to form a complex that represses the expression of a diverse set of yeast genes. This prompted us to examine the effect of sin3Delta and rpd3Delta mutants on INO2-cat expression. Surprisingly, the sin3Delta allele overexpressed INO2-cat, whereas the rpd3Delta mutant had no effect. We also show that the UME6 gene does not affect the expression of an OPI1-cat reporter. This suggests that Ume6p does not regulate INO2 expression indirectly by regulating OPI1 expression.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/12694624?dopt=Abstract</style></custom1></record></records></xml>