1
|
Nenadic A, Zaman MF, Johansen J, Volpiana MW, Beh CT. Increased Phospholipid Flux Bypasses Overlapping Essential Requirements for the Yeast Sac1p Phosphoinositide Phosphatase and ER-PM Membrane Contact Sites. J Biol Chem 2023; 299:105092. [PMID: 37507017 PMCID: PMC10470028 DOI: 10.1016/j.jbc.2023.105092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 07/13/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023] Open
Abstract
In budding yeast cells, much of the inner surface of the plasma membrane (PM) is covered with the endoplasmic reticulum (ER). This association is mediated by seven ER membrane proteins that confer cortical ER-PM association at membrane contact sites (MCSs). Several of these membrane "tether" proteins are known to physically interact with the phosphoinositide phosphatase Sac1p. However, it is unclear how or if these interactions are necessary for their interdependent functions. We find that SAC1 inactivation in cells lacking the homologous synaptojanin-like genes INP52 and INP53 results in a significant increase in cortical ER-PM MCSs. We show in sac1Δ, sac1tsinp52Δ inp53Δ, or Δ-super-tether (Δ-s-tether) cells lacking all seven ER-PM tethering genes that phospholipid biosynthesis is disrupted and phosphoinositide distribution is altered. Furthermore, SAC1 deletion in Δ-s-tether cells results in lethality, indicating a functional overlap between SAC1 and ER-PM tethering genes. Transcriptomic profiling indicates that SAC1 inactivation in either Δ-s-tether or inp52Δ inp53Δ cells induces an ER membrane stress response and elicits phosphoinositide-dependent changes in expression of autophagy genes. In addition, by isolating high-copy suppressors that rescue sac1Δ Δ-s-tether lethality, we find that key phospholipid biosynthesis genes bypass the overlapping function of SAC1 and ER-PM tethers and that overexpression of the phosphatidylserine/phosphatidylinositol-4-phosphate transfer protein Osh6 also provides limited suppression. Combined with lipidomic analysis and determinations of intracellular phospholipid distributions, these results suggest that Sac1p and ER phospholipid flux controls lipid distribution to drive Osh6p-dependent phosphatidylserine/phosphatidylinositol-4-phosphate counter-exchange at ER-PM MCSs.
Collapse
Affiliation(s)
- Aleksa Nenadic
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Mohammad F Zaman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Jesper Johansen
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Matthew W Volpiana
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Christopher T Beh
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada; Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, British Columbia, Canada.
| |
Collapse
|
2
|
Panessa GM, Tassoni-Tsuchida E, Pires MR, Felix RR, Jekabson R, de Souza-Pinto NC, da Cunha FM, Brandman O, Cussiol JRR. Opi1-mediated transcriptional modulation orchestrates genotoxic stress response in budding yeast. Genetics 2023; 225:iyad130. [PMID: 37440469 PMCID: PMC10691878 DOI: 10.1093/genetics/iyad130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/28/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
In budding yeast, the transcriptional repressor Opi1 regulates phospholipid biosynthesis by repressing expression of genes containing inositol-sensitive upstream activation sequences. Upon genotoxic stress, cells activate the DNA damage response to coordinate a complex network of signaling pathways aimed at preserving genomic integrity. Here, we reveal that Opi1 is important to modulate transcription in response to genotoxic stress. We find that cells lacking Opi1 exhibit hypersensitivity to genotoxins, along with a delayed G1-to-S-phase transition and decreased gamma-H2A levels. Transcriptome analysis using RNA sequencing reveals that Opi1 plays a central role in modulating essential biological processes during methyl methanesulfonate (MMS)-associated stress, including repression of phospholipid biosynthesis and transduction of mating signaling. Moreover, Opi1 induces sulfate assimilation and amino acid metabolic processes, such as arginine and histidine biosynthesis and glycine catabolism. Furthermore, we observe increased mitochondrial DNA instability in opi1Δ cells upon MMS treatment. Notably, we show that constitutive activation of the transcription factor Ino2-Ino4 is responsible for genotoxin sensitivity in Opi1-deficient cells, and the production of inositol pyrophosphates by Kcs1 counteracts Opi1 function specifically during MMS-induced stress. Overall, our findings highlight Opi1 as a critical sensor of genotoxic stress in budding yeast, orchestrating gene expression to facilitate appropriate stress responses.
Collapse
Affiliation(s)
- Giovanna Marques Panessa
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| | - Eduardo Tassoni-Tsuchida
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - Marina Rodrigues Pires
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| | - Rodrigo Rodrigues Felix
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| | - Rafaella Jekabson
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| | | | - Fernanda Marques da Cunha
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| | - Onn Brandman
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - José Renato Rosa Cussiol
- Departamento de Bioquímica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP 04023-900, Brazil
| |
Collapse
|
3
|
Zhao Y, Li J, Su R, Liu Y, Wang J, Deng Y. Effect of magnesium ions on glucaric acid production in the engineered Saccharomyces cerevisiae. J Biotechnol 2021; 332:61-71. [PMID: 33812897 DOI: 10.1016/j.jbiotec.2021.03.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 03/16/2021] [Accepted: 03/25/2021] [Indexed: 11/27/2022]
Abstract
Glucaric acid has been successfully produced in Escherichia coli and fungus. Here, we first analyzed the effects of different metal ions on glucaric acid production in the engineered Saccharomyces cerevisiae Bga-3 strain harboring the glucaric acid synthesis pathway. We found that magnesium ions could promote the growth rate of yeast cells, and thus, increase the glucaric acid production by elevating the glucose and myo-inositol utilization of Bga-3 strain. RNA-Seq transcriptome analysis results showed that the upregulation of genes involved in the gluconeogenesis pathway, as well as the downregulation of genes associated with the glycolysis pathway and pentose phosphate pathway in response to MgCl2 were all benefit for the enhancement of the glucose-6-phosphate flux, which was the precursor for myo-inositol and glucaric acid. In addition, we found that MgCl2 could also increase the activity of MIOX4, which was also crucial for glucaric acid synthesis. At last, a final glucaric acid titer of 10.6 g/L, the highest reported titer, was achieved in the fed-batch fermentation using a 5-L bioreactor by adding 100 mM MgCl2. Our findings will provide a new way of promoting the production of other chemicals in the engineered yeast cells.
Collapse
Affiliation(s)
- Yunying Zhao
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Jie Li
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Ruifang Su
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Yingli Liu
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Beijing Technology & Business University, Beijing, 100048, China
| | - Jing Wang
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Beijing Technology & Business University, Beijing, 100048, China
| | - Yu Deng
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China; Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
| |
Collapse
|
4
|
Camelo C, Vilas-Boas F, Cepeda AP, Real C, Barros-Martins J, Pinto F, Soares H, Marinho HS, Cyrne L. Opi1p translocation to the nucleus is regulated by hydrogen peroxide in Saccharomyces cerevisiae. Yeast 2017; 34:383-395. [PMID: 28581036 DOI: 10.1002/yea.3240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 05/29/2017] [Accepted: 05/30/2017] [Indexed: 01/12/2023] Open
Abstract
During exposure of yeast cells to low levels of hydrogen peroxide (H2 O2 ), the expression of several genes is regulated for cells to adapt to the surrounding oxidative environment. Such adaptation involves modification of plasma membrane lipid composition, reorganization of ergosterol-rich microdomains and altered gene expression of proteins involved in lipid and vesicle traffic, to decrease permeability to exogenous H2 O2 . Opi1p is a transcriptional repressor that is inactive when present at the nuclear membrane/endoplasmic reticulum, but represseses transcription of inositol upstream activating sequence (UASINO )-containing genes, many of which are involved in the synthesis of phospholipids and fatty acids, when it is translocated to the nucleus. We investigated whether H2 O2 in concentrations inducing adaptation regulates Opi1p function. We found that, in the presence of H2 O2 , GFP-Opi1p fusion protein translocates to the nucleus and, concomitantly, the expression of UASINO -containing genes is affected. We also investigated whether cysteine residues of Opi1p were implicated in the H2 O2 -mediated translocation of this protein to the nucleus and identified cysteine residue 159 as essential for this process. Our work shows that Opi1p is redox-regulated and establishes a new mechanism of gene regulation involving Opi1p, which is important for adaptation to H2 O2 in yeast cells. Copyright © 2017 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Carolina Camelo
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Filipe Vilas-Boas
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Andreia Pereira Cepeda
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Carla Real
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Joana Barros-Martins
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Francisco Pinto
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.,BioISI - Biosystems and Integrative Sciences Institute, Campo Grande, Lisboa, Portugal
| | - Helena Soares
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.,Escola Superior de Tecnologia da Saúde de Lisboa, 1990-096, Lisboa, Portugal
| | - H Susana Marinho
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.,Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| | - Luisa Cyrne
- Centro de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal.,Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisboa, Portugal
| |
Collapse
|
5
|
Zhang L, Di J. The transcriptional activator Ino2p dissociates from the yeast INM1 promoter in induction. DNA Cell Biol 2014; 33:863-8. [PMID: 25211324 DOI: 10.1089/dna.2014.2397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mood stabilizers lithium and valproates are widely used in the treatment of bipolar disorder. It has been shown that these drugs can affect the inositol monophosphatase activity and thus the inositol de novo biosynthesis. However, the molecular mechanism of this action has thus far been vague. As such, characterizing the regulation of the gene encoding inositol monophosphatase at the molecular level can help to understand the bipolar disorder. As the model organism, the inositol monophosphatase is encoded by INM1 in Saccharomyces cerevisiae. In this study, we showed, using real-time reverse transcriptase polymerase chain reaction analysis, that INM1 is expressed in the presence of inositol, suggesting that the presence of inositol is required for INM1 transcriptional activation. We also demonstrated, using chromatin immunoprecipitation, that Ino2p is present at the promoter under uninduced conditions. Upon induction, Ino2p dissociates from the INM1 promoter. Furthermore, chromatin remodelers Ino80p and Snf2p are recruited to INM1 promoter upon induction as well as histone acetylases Gcn5p and Esa1p. Altogether, we have provided the evidence which describes how the transcriptional activator and coactivators participate in INM1 activation.
Collapse
Affiliation(s)
- Lingzhi Zhang
- 1 Department of Emergency, Shengjing Hospital of China Medical University , Shenyang, China
| | | |
Collapse
|
6
|
Wimalarathna RN, Pan PY, Shen CH. Co-dependent recruitment of Ino80p and Snf2p is required for yeast CUP1 activation. Biochem Cell Biol 2014; 92:69-75. [DOI: 10.1139/bcb-2013-0097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In yeast, Ace1p-dependent induction of CUP1 is responsible for protecting cells from copper toxicity. Although the mechanism of yeast CUP1 induction has been studied intensively, it is still uncertain which chromatin remodelers are involved in CUP1 transcriptional activation. Here, we show that yeast cells are inviable in the presence of copper when either chromatin remodeler, Ino80p or Snf2p, is not present. This inviability is due to the lack of CUP1 expression in ino80Δ and snf2Δ cells. Subsequently, we observe that both Ino80p and Snf2p are present at the promoter and they are responsible for recruiting chromatin remodeling activity to the CUP1 promoter under induced conditions. These results suggest that they directly participate in CUP1 transcriptional activation. Furthermore, the codependent recruitment of both INO80 and SWI/SNF depends on the presence of the transcriptional activator, Ace1p. We also demonstrate that both remodelers are required to recruit RNA polymerase II and targeted histone acetylation, indicating that remodelers are recruited to the CUP1 promoter before RNA polymerase II and histone acetylases. These observations provide evidence for the mechanism of CUP1 induction. As such, we propose a model that describes novel insight into the order of events in CUP1 activation.
Collapse
Affiliation(s)
- Roshini N. Wimalarathna
- Department of Biology, College of Staten Island, City University of New York, 2800 Victory Blvd., Staten Island, NY 10314, USA
- PhD Program in Biology, The Graduate Center, City University of New York, 365 Fifth Avenue, NY 10016, USA
| | - Po Yun Pan
- Department of Biology, College of Staten Island, City University of New York, 2800 Victory Blvd., Staten Island, NY 10314, USA
| | - Chang-Hui Shen
- Department of Biology, College of Staten Island, City University of New York, 2800 Victory Blvd., Staten Island, NY 10314, USA
- PhD Program in Biology, The Graduate Center, City University of New York, 365 Fifth Avenue, NY 10016, USA
- Institute for Macromolecular Assemblies, City University of New York, 2800 Victory Blvd, Staten Island, NY 10314, USA
| |
Collapse
|
7
|
Lee SW, Kim E, Kim JS, Oh MK. Artificial transcription regulator as a tool for improvement of cellular property in Saccharomyces cerevisiae. Chem Eng Sci 2013. [DOI: 10.1016/j.ces.2012.09.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
8
|
El Idrissi A, Shen CH, L'amoreaux WJ. Neuroprotective role of taurine during aging. Amino Acids 2013; 45:735-50. [PMID: 23963537 DOI: 10.1007/s00726-013-1544-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 06/24/2013] [Indexed: 11/26/2022]
Abstract
Aging of the brain is characterized by several neurochemical modifications involving structural proteins, neurotransmitters, neuropeptides and related receptors. Alterations of neurochemical indices of synaptic function are indicators of age-related impairment of central functions, such as locomotion, memory and sensory performances. Several studies demonstrate that ionotropic GABA receptors, glutamate decarboxylase (GAD), and somatostatinergic subpopulations of GABAergic neurons are markedly decreased in experimental animal brains during aging. Additionally, levels of several neuropeptides co-expressed with GAD decrease during aging. Thus, the age-related decline in cognitive functions could be attributable, at least in part, to decrements in GABA inhibitory neurotransmission. In this study, we showed that chronic supplementation of taurine to aged mice significantly ameliorated the age-dependent decline in spatial memory acquisition and retention. We also demonstrated that concomitant with the amelioration in cognitive function, taurine caused significant alterations in the GABAergic and somatostatinergic system. These changes included (1) increased levels of the neurotransmitters GABA and glutamate, (2) increased expression of both isoforms of GAD (65 and 67) and the neuropeptide somatostatin, (3) decreased hippocampal expression of the β3 subunits of the GABAA receptor, (4) increased expression in the number of somatostatin-positive neurons, (5) increased amplitude and duration of population spikes recorded from CA1 in response to Schaefer collateral stimulation and (6) enhanced paired pulse facilitation in the hippocampus. These specific alterations of the inhibitory system caused by taurine treatment oppose those naturally occurring in the aging brain, suggesting a protective role of taurine in this process. An increased understanding of age-related neurochemical changes in the GABAergic system will be important in elucidating the underpinnings of the functional changes of aging. Taurine supplementation might help forestall the age-related decline in cognitive functions through interaction with the GABAergic system.
Collapse
Affiliation(s)
- Abdeslem El Idrissi
- Department of Biology, Center for Developmental Neuroscience, City University of New York Graduate School, Staten Island, NY, 10314, USA,
| | | | | |
Collapse
|
9
|
Changes in Gene Expression at Inhibitory Synapses in Response to Taurine Treatment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 775:187-94. [DOI: 10.1007/978-1-4614-6130-2_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
|
10
|
Chromatin repositioning activity and transcription machinery are both recruited by Ace1p in yeast CUP1 activation. Biochem Biophys Res Commun 2012; 422:658-63. [PMID: 22609398 DOI: 10.1016/j.bbrc.2012.05.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 05/09/2012] [Indexed: 11/22/2022]
Abstract
The relationship among transcriptional activators, nucleosome repositioning activity and transcription machinery at the yeast CUP1 gene was addressed. CUP1 encodes a cysteine-rich, copper-binding metallothionein that protects cells against copper toxicity through its ability to sequester copper. The induction of CUP1 requires the presence of Ace1p and the binding of Ace1p at the CUP1 promoter during activation provides evidence that Ace1p is directly involved in CUP1 induction. Furthermore, transcriptional activation of CUP1 resulted in nucleosome repositioning at the CUP1 promoter and sequences further downstream in the coding region, suggesting a gene-wide chromatin remodeling activity. Such remodeling activity depends on the presence of transcription activator Ace1p. The recruitment of RNA polymerase II also requires the presence of Ace1p. Therefore, these observations provide insight into the molecular mechanism of CUP1 activation.
Collapse
|
11
|
Rupwate SD, Rupwate PS, Rajasekharan R. Regulation of lipid biosynthesis by phosphatidylinositol-specific phospholipase C through the transcriptional repression of upstream activating sequence inositol containing genes. FEBS Lett 2012; 586:1555-60. [PMID: 22673525 DOI: 10.1016/j.febslet.2012.04.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 04/11/2012] [Accepted: 04/12/2012] [Indexed: 10/28/2022]
Abstract
The regulation of phospholipid biosynthesis in Saccharomyces cerevisiae through cis-acting upstream activating sequence inositol (UAS(ino)) and trans-acting elements, such as the INO2-INO4 complex and OPI1 by inositol supplementation in growth is thoroughly studied. In this study, we provide evidence for the regulation of lipid biosynthesis by phosphatidylinositol-specific phospholipase C (PLC) through UAS(ino) and the trans-acting elements. Gene expression analysis and radiolabelling experiments demonstrated that the overexpression of rice PLC in yeast cells altered phospholipid biosynthesis at the levels of transcriptional and enzyme activity. This is the first report implicating PLC in the direct regulation of lipid biosynthesis.
Collapse
Affiliation(s)
- Sunny D Rupwate
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | | |
Collapse
|
12
|
Konarzewska P, Esposito M, Shen CH. INO1 induction requires chromatin remodelers Ino80p and Snf2p but not the histone acetylases. Biochem Biophys Res Commun 2012; 418:483-8. [PMID: 22281492 DOI: 10.1016/j.bbrc.2012.01.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Accepted: 01/08/2012] [Indexed: 11/19/2022]
Abstract
Transcriptional co-activators contribute to gene expression through different mechanisms. We used various biochemical tools available for Saccharomyces cerevisiae to examine the mechanism of INO1 expression. INO1 encodes inositol-3-phosphate synthase, which catalyzes the rate-limiting step in the synthesis of inositol, a key player in phospholipid biosynthesis. Herein, we had demonstrated that the recruitment of histone acetylases Gcn5p and Esa1p mainly relied on the presence of transcriptional activator Ino2p during INO1 activation. However, the presence of the chromatin remodelers, Ino80p and Snf2p, may contribute to the additive effect of Gcn5p recruitment. We also showed that the recruitment of chromatin remodelers, Ino80p and Snf2p, is independent of the presence of histone acetylases. Furthermore, INO1 expression can be activated exclusively by the activator and chromatin remodelers, suggesting a dispensable role of histone acetylases in INO1 induction. Therefore, our data provide a mechanism for cross talk within transcriptional co-activators during INO1 activation.
Collapse
Affiliation(s)
- Paulina Konarzewska
- Department of Biology, College of Staten Island, City University of New York, 2800 Victory Blvd., Staten Island, NY 10314, United States
| | | | | |
Collapse
|