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Sanz AB, Díez-Muñiz S, Moya J, Petryk Y, Nombela C, Rodríguez-Peña JM, Arroyo J. Systematic Identification of Essential Genes Required for Yeast Cell Wall Integrity: Involvement of the RSC Remodelling Complex. J Fungi (Basel) 2022; 8:jof8070718. [PMID: 35887473 PMCID: PMC9323250 DOI: 10.3390/jof8070718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 12/04/2022] Open
Abstract
Conditions altering the yeast cell wall lead to the activation of an adaptive transcriptional response mainly governed by the cell wall integrity (CWI) mitogen-activated protein kinase (MAPK) pathway. Two high-throughput screenings were developed using the yTHC collection of yeast conditional mutant strains to systematically identify essential genes related to cell wall integrity, and those required for the transcriptional program elicited by cell wall stress. Depleted expression of 52 essential genes resulted in hypersensitivity to the dye Calcofluor white, with chromatin organization, Golgi vesicle transport, rRNA processing, and protein glycosylation processes, as the most highly representative functional groups. Via a flow cytometry-based quantitative assay using a CWI reporter plasmid, 97 strains exhibiting reduced gene-reporter expression levels upon stress were uncovered, highlighting genes associated with RNA metabolism, transcription/translation, protein degradation, and chromatin organization. This screening also led to the discovery of 41 strains displaying a basal increase in CWI-associated gene expression, including mainly putative cell wall-related genes. Interestingly, several members of the RSC chromatin remodelling complex were uncovered in both screenings. Notably, Rsc9 was necessary to regulate the gene expression of CWI-related genes both under stress and non-stress conditions, suggesting distinct requirements of the RSC complex for remodelling particular genes.
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2
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Nishiumi F, Kawai Y, Nakura Y, Yoshimura M, Wu HN, Hamaguchi M, Kakizawa S, Suzuki Y, Glass JI, Yanagihara I. Blockade of endoplasmic reticulum stress-induced cell death by Ureaplasma parvum vacuolating factor. Cell Microbiol 2021; 23:e13392. [PMID: 34490709 DOI: 10.1111/cmi.13392] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/03/2021] [Accepted: 09/01/2021] [Indexed: 12/11/2022]
Abstract
Previously, we found that Ureaplasma parvum internalised into HeLa cells and cytosolic accumulation of galectin-3. U. parvum induced the host cellular membrane damage and survived there. Here, we conducted vesicular trafficking inhibitory screening in yeast to identify U. parvum vacuolating factor (UpVF). U. parvum triggered endoplasmic reticulum (ER) stress and upregulated the unfolded protein response-related factors, including BiP, P-eIF2 and IRE1 in the host cells, but it blocked the induction of the downstream apoptotic factors. MicroRNA library screening of U. parvum-infected cells and UpVF-transfected cells identified miR-211 and miR-214 as the negative regulators of the apoptotic cascade under ER stress. Transient expression of UpVF induced HeLa cell death with intracellular vacuolization; however, some stable UpVF transformant survived. U. parvum-infected cervical cell lines showed resistance to actinomycin D, and UpVF stable transformant cell lines exhibited resistance to X-ray irradiation, as well as cisplatin and paclitaxel. UpVF expressing cervical cancer xenografts in nude mice also acquired resistance to cisplatin and paclitaxel. A mycoplasma expression vector based on Mycoplasma mycoides, Syn-MBA (multiple banded antigen)-UpVF, reduced HeLa cell survival compared with that of Syn-MBA after 72 hr of infection. These findings together suggest novel mechanisms for Ureaplasma infection and the possible implications for cervical cancer malignancy. TAKE AWAYS: • Ureaplasmal novel virulence factor, UpVF, was identified. • UpVF triggered ER stress but suppressed apoptotic cascade via miR-211 and -214. • UpVF conferred resistance to anticancer treatments both in vivo and in vitro. • Dual expression of MBA and UpVF in JCVI-syn3B showed host cell damage.
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Affiliation(s)
- Fumiko Nishiumi
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan
| | - Yasuhiro Kawai
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan.,Health Evaluation Center, Kanazawa Medical University Himi Municipal Hospital, Toyama, Japan
| | - Yukiko Nakura
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan
| | - Michinobu Yoshimura
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan.,Department of Microbiology and Immunology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Heng Ning Wu
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan
| | - Mitsuhide Hamaguchi
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Emergency and Critical Care Medicine, Kindai University Faculty of Medicine, Osaka, Japan
| | - Shigeyuki Kakizawa
- Bioproduction Research Institute,, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Yo Suzuki
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California, USA
| | - John I Glass
- Synthetic Biology Group, J. Craig Venter Institute, La Jolla, California, USA
| | - Itaru Yanagihara
- Department of Developmental Medicine, Research Institute, Women's and Children's Hospital, Osaka, Japan
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3
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Patrick KL, Wojcechowskyj JA, Bell SL, Riba MN, Jing T, Talmage S, Xu P, Cabello AL, Xu J, Shales M, Jimenez-Morales D, Ficht TA, de Figueiredo P, Samuel JE, Li P, Krogan NJ, Watson RO. Quantitative Yeast Genetic Interaction Profiling of Bacterial Effector Proteins Uncovers a Role for the Human Retromer in Salmonella Infection. Cell Syst 2018; 7:323-338.e6. [PMID: 30077634 PMCID: PMC6160342 DOI: 10.1016/j.cels.2018.06.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/21/2018] [Accepted: 06/21/2018] [Indexed: 11/26/2022]
Abstract
Intracellular bacterial pathogens secrete a repertoire of effector proteins into host cells that are required to hijack cellular pathways and cause disease. Despite decades of research, the molecular functions of most bacterial effectors remain unclear. To address this gap, we generated quantitative genetic interaction profiles between 36 validated and putative effectors from three evolutionarily divergent human bacterial pathogens and 4,190 yeast deletion strains. Correlating effector-generated profiles with those of yeast mutants, we recapitulated known biology for several effectors with remarkable specificity and predicted previously unknown functions for others. Biochemical and functional validation in human cells revealed a role for an uncharacterized component of the Salmonella SPI-2 translocon, SseC, in regulating maintenance of the Salmonella vacuole through interactions with components of the host retromer complex. These results exhibit the power of genetic interaction profiling to discover and dissect complex biology at the host-pathogen interface.
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Affiliation(s)
- Kristin L Patrick
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Jason A Wojcechowskyj
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA
| | - Samantha L Bell
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Morgan N Riba
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Tao Jing
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Sara Talmage
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Pengbiao Xu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Ana L Cabello
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA; Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA; Norman Borlaug Center, Texas A&M University, College Station, TX 77843, USA
| | - Jiewei Xu
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA
| | - Michael Shales
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA
| | - David Jimenez-Morales
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA
| | - Thomas A Ficht
- Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA
| | - Paul de Figueiredo
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA; Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA; Norman Borlaug Center, Texas A&M University, College Station, TX 77843, USA
| | - James E Samuel
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Pingwei Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA.
| | - Robert O Watson
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA.
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4
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Bankapalli LK, Mishra RC, Raychaudhuri S. VopE, a Vibrio cholerae Type III Effector, Attenuates the Activation of CWI-MAPK Pathway in Yeast Model System. Front Cell Infect Microbiol 2017; 7:82. [PMID: 28373966 PMCID: PMC5357651 DOI: 10.3389/fcimb.2017.00082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 03/02/2017] [Indexed: 01/05/2023] Open
Abstract
VopE, a mitochondrial targeting T3SS effector protein of Vibrio cholerae, perturbs innate immunity by modulating mitochondrial dynamics. In the current study, ectopic expression of VopE was found to be toxic in a yeast model system and toxicity was further aggravated in the presence of various stressors. Interestingly, a VopE variant lacking predicted mitochondrial targeting sequence (MTS) also exhibited partial lethality in the yeast system. With the aid of yeast genetic tools and different stressors, we have demonstrated that VopE and its derivative VopEΔMTS modulate cell wall integrity (CWI-MAPK) signaling pathway and have identified several critical residues contributing to the lethality of VopE. Furthermore, co-expression of two effectors VopEΔMTS and VopX, interfering with the CWI-MAPK cellular pathway can partially suppress the VopX mediated yeast growth inhibition. Taken together, these results suggest that VopE alters signaling through the CWI-MAPK pathway, and demonstrates the usefulness of yeast model system to gain additional insights on the functionality of VopE.
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Affiliation(s)
- Leela K Bankapalli
- Molecular Biology and Microbial Physiology, Institute of Microbial Technology Chandigarh, India
| | - Rahul C Mishra
- Molecular Biology and Microbial Physiology, Institute of Microbial Technology Chandigarh, India
| | - Saumya Raychaudhuri
- Molecular Biology and Microbial Physiology, Institute of Microbial Technology Chandigarh, India
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5
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Popa C, Coll NS, Valls M, Sessa G. Yeast as a Heterologous Model System to Uncover Type III Effector Function. PLoS Pathog 2016; 12:e1005360. [PMID: 26914889 PMCID: PMC4767418 DOI: 10.1371/journal.ppat.1005360] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Type III effectors (T3E) are key virulence proteins that are injected by bacterial pathogens inside the cells of their host to subvert cellular processes and contribute to disease. The budding yeast Saccharomyces cerevisiae represents an important heterologous system for the functional characterisation of T3E proteins in a eukaryotic environment. Importantly, yeast contains eukaryotic processes with low redundancy and are devoid of immunity mechanisms that counteract T3Es and mask their function. Expression in yeast of effectors from both plant and animal pathogens that perturb conserved cellular processes often resulted in robust phenotypes that were exploited to elucidate effector functions, biochemical properties, and host targets. The genetic tractability of yeast and its amenability for high-throughput functional studies contributed to the success of this system that, in recent years, has been used to study over 100 effectors. Here, we provide a critical view on this body of work and describe advantages and limitations inherent to the use of yeast in T3E research. “Favourite” targets of T3Es in yeast are cytoskeleton components and small GTPases of the Rho family. We describe how mitogen-activated protein kinase (MAPK) signalling, vesicle trafficking, membrane structures, and programmed cell death are also often altered by T3Es in yeast and how this reflects their function in the natural host. We describe how effector structure–function studies and analysis of candidate targeted processes or pathways can be carried out in yeast. We critically analyse technologies that have been used in yeast to assign biochemical functions to T3Es, including transcriptomics and proteomics, as well as suppressor, gain-of-function, or synthetic lethality screens. We also describe how yeast can be used to select for molecules that block T3E function in search of new antibacterial drugs with medical applications. Finally, we provide our opinion on the limitations of S. cerevisiae as a model system and its most promising future applications.
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Affiliation(s)
- Crina Popa
- Genetics Department, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Catalonia, Spain
| | - Núria S. Coll
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Catalonia, Spain
| | - Marc Valls
- Genetics Department, Universitat de Barcelona, Barcelona, Catalonia, Spain
- Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB), Bellaterra, Catalonia, Spain
- * E-mail: (GS); (MV)
| | - Guido Sessa
- Department of Molecular Biology and Ecology of Plants, Tel Aviv University, Tel Aviv, Israel
- * E-mail: (GS); (MV)
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6
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Fernandez-Piñar P, Alemán A, Sondek J, Dohlman HG, Molina M, Martín H. The Salmonella Typhimurium effector SteC inhibits Cdc42-mediated signaling through binding to the exchange factor Cdc24 in Saccharomyces cerevisiae. Mol Biol Cell 2012; 23:4430-43. [PMID: 23015760 PMCID: PMC3496616 DOI: 10.1091/mbc.e12-03-0243] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Expression of the Salmonella effector SteC in yeast leads to down-regulation of the mating and HOG pathways by Cdc42 inhibition. This is mediated by the SteC N-terminal domain through binding to the GEF Cdc24. SteC alters Cdc24 localization and also interacts with human GEF Vav1, suggesting that SteC could target Cdc42 function in host cells. Intracellular survival of Salmonella relies on the activity of proteins translocated into the host cell by type III secretion systems (T3SS). The protein kinase activity of the T3SS effector SteC is required for F-actin remodeling in host cells, although no SteC target has been identified so far. Here we show that expression of the N-terminal non-kinase domain of SteC down-regulates the mating and HOG pathways in Saccharomyces cerevisiae. Epistasis analyses using constitutively active components of these pathways indicate that SteC inhibits signaling at the level of the GTPase Cdc42. We demonstrate that SteC interacts through its N-terminal domain with the catalytic domain of Cdc24, the sole S. cerevisiae Cdc42 guanine nucleotide exchange factor (GEF). SteC also binds to the human Cdc24-like GEF protein Vav1. Moreover, expression of human Cdc42 suppresses growth inhibition caused by SteC. Of interest, the N-terminal SteC domain alters Cdc24 cellular localization, preventing its nuclear accumulation. These data reveal a novel functional domain within SteC, raising the possibility that this effector could also target GTPase function in mammalian cells. Our results also highlight the key role of the Cdc42 switch in yeast mating and HOG pathways and provide a new tool to study the functional consequences of Cdc24 localization.
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Affiliation(s)
- Pablo Fernandez-Piñar
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, and Instituto Ramón y Cajal de Investigaciones Sanitarias, 28040 Madrid, Spain
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7
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Lisa-Santamaría P, Jiménez A, Revuelta JL. The protein factor-arrest 11 (Far11) is essential for the toxicity of human caspase-10 in yeast and participates in the regulation of autophagy and the DNA damage signaling. J Biol Chem 2012; 287:29636-47. [PMID: 22782902 DOI: 10.1074/jbc.m112.344192] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The heterologous expression of human caspase-10 in Saccharomyces cerevisiae induces a lethal phenotype, which includes some hallmarks of apoptosis and autophagy, alterations in the intra-S checkpoint, and cell death. To determine the cellular processes and pathways that are responsible of the caspase-10-induced cell death we have designed a loss-of-function screening system to identify genes that are essential for the lethal phenotype. We observed that the ER-Golgi-localized family of proteins Far, MAPK signaling, the autophagy machinery, and several kinases and phosphatases are essential for caspase-10 toxicity. We also found that the expression of caspase-10 elicits a simultaneous activation of the MAP kinases Fus3, Kss1, and Slt2. Furthermore, the protein Far11, which is a target of MAP kinases, is essential for the dephosphorylation of Atg13 and, consequently, for the induction of autophagy. In addition, Far11 participates in the regulation of the DNA damage response through the dephosphorylation of Rad53. Finally, we have also demonstrated that Far11 is able to physically interact with the phosphatases Pph21, Pph22, and Pph3. Overall, our results indicate that the expression of human caspase-10 in S. cerevisiae activates an intracellular death signal that depends on the Far protein complex and that Far11 may function as a regulator subunit of phosphatases in different processes, thus representing a mechanistic link between them.
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Affiliation(s)
- Patricia Lisa-Santamaría
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, CSIC/Universidad de Salamanca, Campus Miguel de Unamuno, E-37007 Salamanca, Spain
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8
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Schleker S, Garcia-Garcia J, Klein-Seetharaman J, Oliva B. Prediction and comparison of Salmonella-human and Salmonella-Arabidopsis interactomes. Chem Biodivers 2012; 9:991-1018. [PMID: 22589098 PMCID: PMC3407687 DOI: 10.1002/cbdv.201100392] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Salmonellosis caused by Salmonella bacteria is a food-borne disease and a worldwide health threat causing millions of infections and thousands of deaths every year. This pathogen infects an unusually broad range of host organisms including human and plants. A better understanding of the mechanisms of communication between Salmonella and its hosts requires identifying the interactions between Salmonella and host proteins. Protein-protein interactions (PPIs) are the fundamental building blocks of communication. Here, we utilize the prediction platform BIANA to obtain the putative Salmonella-human and Salmonella-Arabidopsis interactomes based on sequence and domain similarity to known PPIs. A gold standard list of Salmonella-host PPIs served to validate the quality of the human model. 24,726 and 10,926 PPIs comprising interactions between 38 and 33 Salmonella effectors and virulence factors with 9,740 human and 4,676 Arabidopsis proteins, respectively, were predicted. Putative hub proteins could be identified, and parallels between the two interactomes were discovered. This approach can provide insight into possible biological functions of so far uncharacterized proteins. The predicted interactions are available via a web interface which allows filtering of the database according to parameters provided by the user to narrow down the list of suspected interactions. The interactions are available via a web interface at http://sbi.imim.es/web/SHIPREC.php.
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Affiliation(s)
- Sylvia Schleker
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-5), 52425 Jülich, Germany
| | - Javier Garcia-Garcia
- Structural Bioinformatics Group (GRIB-IMIM). Universitat Pompeu Fabra. Barcelona Research Park of Biomedicine (PRBB), Barcelona 08003, Catalonia, Spain (phone: +34 933 160 509; fax: +34 933 160 550
| | - Judith Klein-Seetharaman
- Forschungszentrum Jülich, Institute of Complex Systems (ICS-5), 52425 Jülich, Germany
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15260, USA (phone: +1 412 383 7325; fax: +1 412 648 8998
| | - Baldo Oliva
- Structural Bioinformatics Group (GRIB-IMIM). Universitat Pompeu Fabra. Barcelona Research Park of Biomedicine (PRBB), Barcelona 08003, Catalonia, Spain (phone: +34 933 160 509; fax: +34 933 160 550
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9
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Schleker S, Sun J, Raghavan B, Srnec M, Müller N, Koepfinger M, Murthy L, Zhao Z, Klein-Seetharaman J. The current Salmonella-host interactome. Proteomics Clin Appl 2011; 6:117-33. [PMID: 22213674 DOI: 10.1002/prca.201100083] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Revised: 09/26/2011] [Accepted: 09/27/2011] [Indexed: 11/11/2022]
Abstract
Salmonella bacteria cause millions of infections and thousands of deaths every year. This pathogen has an unusually broad host range including humans, animals, and even plants. During infection, Salmonella expresses a variety of virulence factors and effectors that are delivered into the host cell triggering cellular responses through protein-protein interactions (PPI) with host cell proteins which make the pathogen's invasion and replication possible. To speed up proteomic efforts in elucidating Salmonella-host interactomes, we carried out a survey of the currently published Salmonella-host PPI. Such a list can serve as the gold standard for computational models aimed at predicting Salmonella-host interactomes through integration of large-scale biological data sources. Manual literature and database search of >2200 journal articles and >100 databases resulted in a gold standard list of currently 62 PPI, including primarily interactions of Salmonella proteins with human and mouse proteins. Only six of these interactions were directly retrievable from PPI databases and 16 were highlighted in databases featuring literature extracts. Thus, the literature survey resulted in the most complete interactome available to date for Salmonella. Pathway analysis using Ingenuity and Broad Gene Set Enrichment Analysis (GSEA) software revealed among general pathways such as MAPK signaling in particular those related to cell death as well as cell morphology, turnover, and interactions, in addition to response to not only Salmonella but also other pathogenic - viral and bacterial - infections. The list of interactions is available at http://www.shiprec.org/indicationslist.htm.
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Affiliation(s)
- Sylvia Schleker
- Forschungszentrum Jülich, Institute of Complex Systems, Jülich, Germany
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10
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Rodríguez-Escudero I, Ferrer NL, Rotger R, Cid VJ, Molina M. Interaction of the Salmonella Typhimurium effector protein SopB with host cell Cdc42 is involved in intracellular replication. Mol Microbiol 2011; 80:1220-40. [DOI: 10.1111/j.1365-2958.2011.07639.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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11
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de Llanos R, Hernández-Haro C, Barrio E, Querol A, Fernández-Espinar MT, Molina M. Differences in activation of MAP kinases and variability in the polyglutamine tract of Slt2 in clinical and non-clinical isolates of Saccharomyces cerevisiae. Yeast 2010; 27:549-61. [PMID: 20586115 DOI: 10.1002/yea.1799] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The concept of Saccharomyces cerevisiae as an emerging opportunistic pathogen is relatively new and it is due to an increasing number of human infections during the past 20 years. There are still few studies addressing the mechanisms of infection of this yeast species. Moreover, little is known about how S. cerevisiae cells sense and respond to the harsh conditions imposed by the host, and whether this response is different between clinical isolates and non-pathogenic strains. In this regard, mitogen-activated protein kinase (MAPK) pathways constitute one of the major mechanisms for controlling transcriptional responses and, in some cases, virulence in fungi. Here we show differences among clinical and non-clinical isolates of S. cerevisiae in the level of activation of the MAPKs Kss1, which controls pseudohyphal and invasive growth, and Slt2, which is required for maintaining the integrity of the cell wall under stress conditions and in the absence of stimulating conditions. Moreover, we report for the first time the existence of length variability in SLT2 alleles of strains with a clinical origin. This is due to the expansion in the number of glutamine-encoding triplets in the microsatellite region coding for the polyglutamine (poly-Q) tract of this gene, which range from 12 to more than 38 repetitions. We suggest that this variability may influence biological features of the Slt2 protein, allowing it to adapt swiftly in order to survive in unusual environments.
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Affiliation(s)
- Rosa de Llanos
- Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de los Alimentos, CSIC, PO Box 73, 46100 Burjassot, Valencia, Spain
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12
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Tripathi R, Singh Naorem S, Dureja C, Haldar S, Mondal AK, Raychaudhuri S. VopF, a type III effector protein from a non-O1, non-O139 Vibrio cholerae strain, demonstrates toxicity in a Saccharomyces cerevisiae model. J Med Microbiol 2010; 59:17-24. [PMID: 19779031 DOI: 10.1099/jmm.0.012336-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
VopF, a type III effector protein, has been identified as a contributory factor to the intestinal colonization of type III secretion system-positive, non-O1, non-O139 Vibrio cholerae strains. To gain more insight into the function of VopF, a yeast model was developed. Using this model, it was found that ectopic expression of VopF conferred toxicity in yeast.
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Affiliation(s)
- Ranjana Tripathi
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
| | - Santa Singh Naorem
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
| | - Chetna Dureja
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
| | - Swati Haldar
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
| | - Alok K Mondal
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
| | - Saumya Raychaudhuri
- Institute of Microbial Technology, Molecular Biology Division, Chandigarh, Council of Scientific and Industrial Research (CSIR), New Delhi 160036, India
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13
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Different modulation of the outputs of yeast MAPK-mediated pathways by distinct stimuli and isoforms of the dual-specificity phosphatase Msg5. Mol Genet Genomics 2009; 281:345-59. [PMID: 19123063 DOI: 10.1007/s00438-008-0415-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Accepted: 12/12/2008] [Indexed: 02/03/2023]
Abstract
The activity of protein phosphatases on mitogen-activated protein kinases (MAPKS) is essential in the modulation of the final outcome of MAPK-signalling pathways. The yeast dual-specificity phosphatase (DSP) Msg5, expressed as two isoforms of different length, dephosphorylates the MAPKs of mating and cell integrity pathways, Fus3 and Slt2, respectively, but its action on the MAPK Kss1 is unclear. Here we analyse the global impact of Msg5 on the yeast transcriptome. Both Fus3- and Slt2- but not Kss1-mediated gene expression is induced in cells lacking Msg5. However, although these cells show high Slt2 phosphorylation, the Rlm1-dependent Slt2-regulated transcriptional response is weak. Therefore, mechanisms concomitant with Slt2 phosphorylation are required for a strong Rlm1 activation. The limited Slt2 activity on Rlm1 is not a specific effect on this substrate but a consequence of its low kinase activity in msg5Delta cells. Lack of Msg5 does not increase Kss1 phosphorylation although both proteins physically interact. Both Msg5 isoforms interact similarly with Slt2, whereas the long form binds Fus3 with higher affinity and consequently down-regulates it more efficiently than the short one. We propose that specific binding of DSP isoforms to distinct MAPKs provides a novel mechanism for fine tuning different pathways by the same phosphatase.
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Siggers KA, Lesser CF. The Yeast Saccharomyces cerevisiae: a versatile model system for the identification and characterization of bacterial virulence proteins. Cell Host Microbe 2008; 4:8-15. [PMID: 18621006 DOI: 10.1016/j.chom.2008.06.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Microbial pathogens utilize complex secretion systems to deliver proteins into host cells. These effector proteins target and usurp host cell processes to promote infection and cause disease. While secretion systems are conserved, each pathogen delivers its own unique set of effectors. The identification and characterization of these effector proteins has been difficult, often limited by the lack of detectable signal sequences and functional redundancy. Model systems including yeast, worms, flies, and fish are being used to circumvent these issues. This technical review details the versatility and utility of yeast Saccharomyces cerevisiae as a system to identify and characterize bacterial effectors.
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Affiliation(s)
- Keri A Siggers
- Department of Medicine (Microbiology and Molecular Genetics), Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, Cambridge, MA 02139, USA
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Rodríguez-Escudero I, Rotger R, Cid VJ, Molina M. Inhibition of Cdc42-dependent signalling in Saccharomyces cerevisiae by phosphatase-dead SigD/SopB from Salmonella typhimurium. MICROBIOLOGY-SGM 2007; 152:3437-3452. [PMID: 17074912 DOI: 10.1099/mic.0.29186-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Heterologous expression of bacterial virulence factors in Saccharomyces cerevisiae is a feasible approach to study their molecular function. The authors have previously reported that the Salmonella typhimurium SigD protein, a phosphatidylinositol phosphatase involved in invasion of the host cell, inhibits yeast growth, presumably by depleting an essential pool of phosphatidylinositol 4,5-bisphosphate, and also that a catalytically inactive version, SigD(R468A), was able to arrest growth by a different mechanism that involved disruption of the actin cytoskeleton. This paper describes marked differences between the phenotypes elicited by expression of SigD and SigD(R468A) in yeast. First, expression of SigD(R468A) caused accumulation of large unbudded cells and loss of septin organization, while SigD expression caused none of these effects. Second, growth inhibition by SigD(R468A) was mediated by a cell cycle arrest in G2 dependent on the Swe1 morphogenetic checkpoint, but SigD-induced growth inhibition was cell cycle independent. And third, SigD caused strong activation of the yeast MAP kinase Slt2, whereas SigD(R468A) rather inactivated another MAP kinase, Kss1. In a screen for suppressors of SigD(R468A)-induced growth arrest by overexpression of a yeast cDNA library, the Cdc42 GTPase was isolated. Furthermore, SigD(R468A) was co-purified with Cdc42 from yeast lysates. It is concluded that the Salmonella SigD protein deprived of its phosphatase activity is able to disrupt yeast morphogenesis by interfering with Cdc42 function, opening the possibility that the SigD N-terminal region might directly modulate small GTPases from the host during infection.
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Affiliation(s)
- Isabel Rodríguez-Escudero
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Rafael Rotger
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Víctor J Cid
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - María Molina
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
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Hardwidge PR, Donohoe S, Aebersold R, Finlay BB. Proteomic analysis of the binding partners to enteropathogenic Escherichia coli virulence proteins expressed in Saccharomyces cerevisiae. Proteomics 2006; 6:2174-9. [PMID: 16552782 DOI: 10.1002/pmic.200500523] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Enteropathogenic Escherichia coli (EPEC) is an enteric human pathogen responsible for much worldwide morbidity and mortality. EPEC uses a type III secretion system to inject bacterial proteins into the cytosol of intestinal epithelial cells to cause diarrheal disease. We are interested in determining the host proteins to which EPEC translocator and effector proteins bind during infection. To facilitate protein enrichment, we created fusions between GST and EPEC virulence proteins, and expressed these fusions individually in Saccharomyces cerevisiae. The biology of S. cerevisiae is well understood and often employed as a model eukaryote to study the function of bacterial virulence factors. We isolated the yeast proteins that interact with individual EPEC proteins by affinity purifying against the GST tag. These complexes were subjected to ICAT combined with ESI-MS/MS. Database searching of sequenced peptides provided a list of proteins that bound specifically to each EPEC virulence protein. The dataset suggests several potential mammalian targets of these proteins that may guide future experimentation.
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Affiliation(s)
- Philip R Hardwidge
- Veterinary Science Department, South Dakota State University, Brookings, SD, USA.
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17
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Alemán A, Rodríguez-Escudero I, Mallo GV, Cid VJ, Molina M, Rotger R. The amino-terminal non-catalytic region of Salmonella typhimurium SigD affects actin organization in yeast and mammalian cells. Cell Microbiol 2005; 7:1432-46. [PMID: 16153243 DOI: 10.1111/j.1462-5822.2005.00568.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The internalization of Salmonella into epithelial cells relies on the function of bacterial proteins which are injected into the cell by a specialized type III secretion system. Such bacterial effectors interfere with host cell signalling and induce local cytoskeletal rearrangements. One of such effectors is SigD/SopB, which shares homology with mammalian inositol phosphatases. We made use of the Saccharomyces cerevisiae model for elucidating new aspects of SigD function. Endogenous expression of SigD in yeast caused severe growth inhibition. Surprisingly, sigD alleles mutated in the catalytic site or even deleted for the whole C-terminal phosphatase domain still inhibited yeast growth by inducing loss of actin polarization and precluding the budding process. Accordingly, when expressed in HeLa cells, the same sigD alleles lost the ability of depleting phosphatidylinositol 4,5-bisphosphate from the plasma membrane, but still caused disappearance of actin fibres and loss of adherence. We delineate a region of 25 amino acids (residues 118-142) that is necessary for the effect of SigD on actin in HeLa cells. Our data indicate that SigD exerts a toxic effect linked to its N-terminal region and independent of its phosphatase activity.
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Affiliation(s)
- Ainel Alemán
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Spain
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18
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Parrish WR, Stefan CJ, Emr SD. PtdIns(3)P accumulation in triple lipid-phosphatase-deletion mutants triggers lethal hyperactivation of the Rho1p/Pkc1p cell-integrity MAP kinase pathway. J Cell Sci 2005; 118:5589-601. [PMID: 16306222 DOI: 10.1242/jcs.02649] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In the budding yeast Saccharomyces cerevisiae, the regulation of phosphatidylinositol 3-phosphate [PtdIns(3)P] is an essential function shared by the myotubularin-related phosphatase Ymr1p and the synaptojanin-like phosphatases Sjl2p and Sjl3p. The aim of this study was to gain further insight into the mechanisms underlying the toxicity of PtdIns(3)P accumulation in ymr1Δ sjl2Δ sjl3Δ mutant cells. We conducted a genetic screen to isolate genes that, when overexpressed, would rescue the conditional lethality of ymr1Δ sjl2Δ sjl3Δ triple-mutant cells expressing YMR1 from the dextrose-repressible GAL1 promoter. This approach identified 17 genes that promoted growth of the triple mutant on media containing dextrose. Interestingly, the most frequently isolated gene product was a truncated form of PKC1 (Pkc1-T615) that lacked the C-terminal kinase domain. This Pkc1-T615 fragment also rescued the lethality of ymr1ts sjl2Δ sjl3Δ cells at restrictive temperature, and further mapping of the rescuing activity showed that the N-terminal Rho1-GTP-interacting HR1 domains (Pkc1-T242) were sufficient. This indicated that the PKC1 fragments might act by interfering with Rho1-GTP signal propagation. Consistent with this, deletion of the ROM2 gene, which encodes a major Rho1p guanine-nucleotide exchange factor, bypassed the lethal effect of PtdIns(3)P accumulation in ymr1Δ sjl2Δ sjl3Δ triple-mutant cells. Furthermore, cells deficient in phosphoinositide 3-phosphatase (PI 3-phosphatase) activity were defective for Rho1p/Pkc1p pathway regulation, which included an inability of these cells to adapt to heat stress. Taken together, the results of this study indicated that aberrant Rho1p/Pkc1p signaling contributes to the lethal effects of PtdIns(3)P accumulation in cells deficient in PI 3-phosphatase activity.
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Affiliation(s)
- William R Parrish
- Department of Cellular and Molecular Medicine and the Howard Hughes Medical Institute, University of California at San Diego, School of Medicine, La Jolla, California 92093-0668, USA
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Valdivia RH. Modeling the function of bacterial virulence factors in Saccharomyces cerevisiae. EUKARYOTIC CELL 2005; 3:827-34. [PMID: 15302815 PMCID: PMC500883 DOI: 10.1128/ec.3.4.827-834.2004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Raphael H Valdivia
- Mailing address: Department of Molecular Genetics and Microbiology, Center for Microbial Pathogenesis, Duke University Medical Center, Durham, NC 27710, USA.
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Rodríguez-Escudero I, Hardwidge PR, Nombela C, Cid VJ, Finlay BB, Molina M. Enteropathogenic Escherichia coli type III effectors alter cytoskeletal function and signalling in Saccharomyces cerevisiae. Microbiology (Reading) 2005; 151:2933-2945. [PMID: 16151205 DOI: 10.1099/mic.0.28072-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) strains cause attaching/effacing lesions in enterocytes through the development of actin-supported pedestals at the site of bacterial adhesion. Pathogenesis requires a type III secretion system (TTSS), which injects into the host cell the intimin receptor, Tir, as well as other effectors called Esps (Escherichia secreted proteins). The genes encoding TTSS structural components and Esps are found within a pathogenicity island called the locus of enterocyte effacement (LEE). This paper describes the application of Saccharomyces cerevisiae as a model to probe the functions of LEE-encoded genes. In a systematic approach, the LEE-encoded translocator and effector proteins were endogenously expressed in yeast and their effects on cell growth, cytoskeletal function and signalling pathways were studied. EspD, EspG and Map inhibited growth by depolarizing the actin cortical cytoskeleton, whereas EspF expression altered the septin cytoskeleton. Specific yeast MAP kinase pathways were activated by EspF, EspG, EspH and Map. The yeast system was used to define functional domains in Map by expressing truncated versions; it was concluded that the C-terminal region of the protein is necessary for actin disruption and toxicity, but not for mitochondrial localization. The utility of the yeast model for functional analyses of EPEC pathogenesis is discussed.
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Affiliation(s)
- Isabel Rodríguez-Escudero
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Pza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Philip R Hardwidge
- Michael Smith Laboratories, #301 - 2185 East Mall, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - César Nombela
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Pza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - Víctor J Cid
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Pza Ramón y Cajal s/n, 28040 Madrid, Spain
| | - B Brett Finlay
- Michael Smith Laboratories, #301 - 2185 East Mall, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - María Molina
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Pza Ramón y Cajal s/n, 28040 Madrid, Spain
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Lommel M, Bagnat M, Strahl S. Aberrant processing of the WSC family and Mid2p cell surface sensors results in cell death of Saccharomyces cerevisiae O-mannosylation mutants. Mol Cell Biol 2004; 24:46-57. [PMID: 14673142 PMCID: PMC303345 DOI: 10.1128/mcb.24.1.46-57.2004] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protein O mannosylation is a crucial protein modification in uni- and multicellular eukaryotes. In humans, a lack of O-mannosyl glycans causes congenital muscular dystrophies that are associated with brain abnormalities. In yeast, protein O mannosylation is vital; however, it is not known why impaired O mannosylation results in cell death. To address this question, we analyzed the conditionally lethal Saccharomyces cerevisiae protein O-mannosyltransferase pmt2 pmt4Delta mutant. We found that pmt2 pmt4Delta cells lyse as small-budded cells in the absence of osmotic stabilization and that treatment with mating pheromone causes pheromone-induced cell death. These phenotypes are partially suppressed by overexpression of upstream elements of the protein kinase C (PKC1) cell integrity pathway, suggesting that the PKC1 pathway is defective in pmt2 pmt4Delta mutants. Congruently, induction of Mpk1p/Slt2p tyrosine phosphorylation does not occur in pmt2 pmt4Delta mutants during exposure to mating pheromone or elevated temperature. Detailed analyses of the plasma membrane sensors of the PKC1 pathway revealed that Wsc1p, Wsc2p, and Mid2p are aberrantly processed in pmt mutants. Our data suggest that in yeast, O mannosylation increases the activity of Wsc1p, Wsc2p, and Mid2p by enhancing their stability. Reduced O mannosylation leads to incorrect proteolytic processing of these proteins, which in turn results in impaired activation of the PKC1 pathway and finally causes cell death in the absence of osmotic stabilization.
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Affiliation(s)
- Mark Lommel
- Institute of Cell Biology and Plant Physiology, University of Regensburg, 93040 Regensburg. Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
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Ruiz C, Escribano V, Morgado E, Molina M, Mazón MJ. Cell-type-dependent repression of yeast a-specific genes requires Itc1p, a subunit of the Isw2p-Itc1p chromatin remodelling complex. MICROBIOLOGY (READING, ENGLAND) 2003; 149:341-351. [PMID: 12624196 DOI: 10.1099/mic.0.25920-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In Saccharomyces cerevisiae MATa haploid cells, the a-specific genes are expressed, whereas in the MATalpha haploid and MATa/alpha diploid cell types their transcription is repressed. It is shown in this report that Itc1p, a component of the ATP-dependent Isw2p-Itc1p chromatin remodelling complex, is required for the repression of a-specific genes. It has previously been reported that disruption of the ITC1 gene leads, in MATalpha cells, to an aberrant cell morphology resembling the polarized mating projection of cells responding to pheromone. The activation of the pheromone signalling pathway in itc1 mutants of both mating types was examined and found to be constitutively active in MATalpha itc1 but not in MATa itc1 cells. Furthermore, unlike the wild-type, MATalpha itc1 and MATa/alpha itc1/itc1 cells secrete a-factor and express significant levels of other a-specific genes. The results indicate that the inappropriate a-factor production in a MATalpha context, due to the derepression of the a-specific genes, produces an autocrine signalling loop that leads to the aberrant morphology displayed by MATalpha itc1 cells. It is suggested that the Isw2p-Itc1p complex contributes to maintain the repressive chromatin structure described for the asg operator present in the promoters of a-specific genes.
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Affiliation(s)
- Cristina Ruiz
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Victoria Escribano
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, C/Arturo Duperier 4, 28029 Madrid, Spain
| | - Eulalia Morgado
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, C/Arturo Duperier 4, 28029 Madrid, Spain
| | - María Molina
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - María J Mazón
- Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, C/Arturo Duperier 4, 28029 Madrid, Spain
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Current awareness on yeast. Yeast 2002; 19:1373-80. [PMID: 12526113 DOI: 10.1002/yea.830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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