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Matthews KR, McCulloch R, Morrison LJ. The within-host dynamics of African trypanosome infections. Philos Trans R Soc Lond B Biol Sci 2016; 370. [PMID: 26150654 PMCID: PMC4528486 DOI: 10.1098/rstb.2014.0288] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
African trypanosomes are single-celled protozoan parasites that are capable of long-term survival while living extracellularly in the bloodstream and tissues of mammalian hosts. Prolonged infections are possible because trypanosomes undergo antigenic variation-the expression of a large repertoire of antigenically distinct surface coats, which allows the parasite population to evade antibody-mediated elimination. The mechanisms by which antigen genes become activated influence their order of expression, most likely by influencing the frequency of productive antigen switching, which in turn is likely to contribute to infection chronicity. Superimposed upon antigen switching as a contributor to trypanosome infection dynamics is the density-dependent production of cell-cycle arrested parasite transmission stages, which limit the infection while ensuring parasite spread to new hosts via the bite of blood-feeding tsetse flies. Neither antigen switching nor developmental progression to transmission stages is driven by the host. However, the host can contribute to the infection dynamic through the selection of distinct antigen types, the influence of genetic susceptibility or trypanotolerance and the potential influence of host-dependent effects on parasite virulence, development of transmission stages and pathogenicity. In a zoonotic infection cycle where trypanosomes circulate within a range of host animal populations, and in some cases humans, there is considerable scope for a complex interplay between parasite immune evasion, transmission potential and host factors to govern the profile and outcome of infection.
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Affiliation(s)
- Keith R Matthews
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK
| | - Richard McCulloch
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Sir Graeme Davies Building, 120 University Place, Glasgow G12 8TA, UK
| | - Liam J Morrison
- Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
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Dejung M, Subota I, Bucerius F, Dindar G, Freiwald A, Engstler M, Boshart M, Butter F, Janzen CJ. Quantitative Proteomics Uncovers Novel Factors Involved in Developmental Differentiation of Trypanosoma brucei. PLoS Pathog 2016; 12:e1005439. [PMID: 26910529 PMCID: PMC4765897 DOI: 10.1371/journal.ppat.1005439] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/15/2016] [Indexed: 11/18/2022] Open
Abstract
Developmental differentiation is a universal biological process that allows cells to adapt to different environments to perform specific functions. African trypanosomes progress through a tightly regulated life cycle in order to survive in different host environments when they shuttle between an insect vector and a vertebrate host. Transcriptomics has been useful to gain insight into RNA changes during stage transitions; however, RNA levels are only a moderate proxy for protein abundance in trypanosomes. We quantified 4270 protein groups during stage differentiation from the mammalian-infective to the insect form and provide classification for their expression profiles during development. Our label-free quantitative proteomics study revealed previously unknown components of the differentiation machinery that are involved in essential biological processes such as signaling, posttranslational protein modifications, trafficking and nuclear transport. Furthermore, guided by our proteomic survey, we identified the cause of the previously observed differentiation impairment in the histone methyltransferase DOT1B knock-out strain as it is required for accurate karyokinesis in the first cell division during differentiation. This epigenetic regulator is likely involved in essential chromatin restructuring during developmental differentiation, which might also be important for differentiation in higher eukaryotic cells. Our proteome dataset will serve as a resource for detailed investigations of cell differentiation to shed more light on the molecular mechanisms of this process in trypanosomes and other eukaryotes.
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Affiliation(s)
- Mario Dejung
- Institute of Molecular Biology (IMB), Ackermannweg 4, Mainz, Germany
| | - Ines Subota
- Department of Cell and Developmental Biology, Biocenter, University Wuerzburg, Am Hubland, Wuerzburg, Germany
| | - Ferdinand Bucerius
- Department Biology I, Genetics, University of Munich (LMU), Großhaderner, Martinsried, Germany
| | - Gülcin Dindar
- Department of Cell and Developmental Biology, Biocenter, University Wuerzburg, Am Hubland, Wuerzburg, Germany
| | - Anja Freiwald
- Institute of Molecular Biology (IMB), Ackermannweg 4, Mainz, Germany
| | - Markus Engstler
- Department of Cell and Developmental Biology, Biocenter, University Wuerzburg, Am Hubland, Wuerzburg, Germany
| | - Michael Boshart
- Department Biology I, Genetics, University of Munich (LMU), Großhaderner, Martinsried, Germany
| | - Falk Butter
- Institute of Molecular Biology (IMB), Ackermannweg 4, Mainz, Germany
- * E-mail: (FB); (CJJ)
| | - Christian J. Janzen
- Department of Cell and Developmental Biology, Biocenter, University Wuerzburg, Am Hubland, Wuerzburg, Germany
- * E-mail: (FB); (CJJ)
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53
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Aresta-Branco F, Pimenta S, Figueiredo LM. A transcription-independent epigenetic mechanism is associated with antigenic switching in Trypanosoma brucei. Nucleic Acids Res 2015; 44:3131-46. [PMID: 26673706 PMCID: PMC4838347 DOI: 10.1093/nar/gkv1459] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 11/28/2015] [Indexed: 12/27/2022] Open
Abstract
Antigenic variation in Trypanosoma brucei relies on periodic switching of variant surface glycoproteins (VSGs), which are transcribed monoallelically by RNA polymerase I from one of about 15 bloodstream expression sites (BES). Chromatin of the actively transcribed BES is depleted of nucleosomes, but it is unclear if this open conformation is a mere consequence of a high rate of transcription, or whether it is maintained by a transcription-independent mechanism. Using an inducible BES-silencing reporter strain, we observed that chromatin of the active BES remains open for at least 24 hours after blocking transcription. This conformation is independent of the cell-cycle stage, but dependent upon TDP1, a high mobility group box protein. For two days after BES silencing, we detected a transient and reversible derepression of several silent BESs within the population, suggesting that cells probe other BESs before commitment to one, which is complete by 48 hours. FACS sorting and subsequent subcloning confirmed that probing cells are switching intermediates capable of returning to the original BES, switch to the probed BES or to a different BES. We propose that regulation of BES chromatin structure is an epigenetic mechanism important for successful antigenic switching.
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Affiliation(s)
- Francisco Aresta-Branco
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - Silvia Pimenta
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - Luisa M Figueiredo
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
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Schulz D, Mugnier MR, Paulsen EM, Kim HS, Chung CWW, Tough DF, Rioja I, Prinjha RK, Papavasiliou FN, Debler EW. Bromodomain Proteins Contribute to Maintenance of Bloodstream Form Stage Identity in the African Trypanosome. PLoS Biol 2015; 13:e1002316. [PMID: 26646171 PMCID: PMC4672894 DOI: 10.1371/journal.pbio.1002316] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 10/30/2015] [Indexed: 01/01/2023] Open
Abstract
Trypanosoma brucei, the causative agent of African sleeping sickness, is transmitted to its mammalian host by the tsetse. In the fly, the parasite's surface is covered with invariant procyclin, while in the mammal it resides extracellularly in its bloodstream form (BF) and is densely covered with highly immunogenic Variant Surface Glycoprotein (VSG). In the BF, the parasite varies this highly immunogenic surface VSG using a repertoire of ~2500 distinct VSG genes. Recent reports in mammalian systems point to a role for histone acetyl-lysine recognizing bromodomain proteins in the maintenance of stem cell fate, leading us to hypothesize that bromodomain proteins may maintain the BF cell fate in trypanosomes. Using small-molecule inhibitors and genetic mutants for individual bromodomain proteins, we performed RNA-seq experiments that revealed changes in the transcriptome similar to those seen in cells differentiating from the BF to the insect stage. This was recapitulated at the protein level by the appearance of insect-stage proteins on the cell surface. Furthermore, bromodomain inhibition disrupts two major BF-specific immune evasion mechanisms that trypanosomes harness to evade mammalian host antibody responses. First, monoallelic expression of the antigenically varied VSG is disrupted. Second, rapid internalization of antibodies bound to VSG on the surface of the trypanosome is blocked. Thus, our studies reveal a role for trypanosome bromodomain proteins in maintaining bloodstream stage identity and immune evasion. Importantly, bromodomain inhibition leads to a decrease in virulence in a mouse model of infection, establishing these proteins as potential therapeutic drug targets for trypanosomiasis. Our 1.25Å resolution crystal structure of a trypanosome bromodomain in complex with I-BET151 reveals a novel binding mode of the inhibitor, which serves as a promising starting point for rational drug design.
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Affiliation(s)
- Danae Schulz
- Laboratory of Lymphocyte Biology, The Rockefeller University, New York, New York, United States of America
| | - Monica R. Mugnier
- Laboratory of Lymphocyte Biology, The Rockefeller University, New York, New York, United States of America
| | - Eda-Margaret Paulsen
- Laboratory of Cell Biology, The Rockefeller University, New York, New York, United States of America
| | - Hee-Sook Kim
- Laboratory of Lymphocyte Biology, The Rockefeller University, New York, New York, United States of America
| | - Chun-wa W. Chung
- Computational and Structural Chemistry, GlaxoSmithKline R&D, Medicines Research Centre, Stevenage, United Kingdom
| | - David F. Tough
- Epinova DPU, Immuno-Inflammation Therapy Area, GlaxoSmithKline, Medicines Research Centre, Stevenage, United Kingdom
| | - Inmaculada Rioja
- Epinova DPU, Immuno-Inflammation Therapy Area, GlaxoSmithKline, Medicines Research Centre, Stevenage, United Kingdom
| | - Rab K. Prinjha
- Epinova DPU, Immuno-Inflammation Therapy Area, GlaxoSmithKline, Medicines Research Centre, Stevenage, United Kingdom
| | - F. Nina Papavasiliou
- Laboratory of Lymphocyte Biology, The Rockefeller University, New York, New York, United States of America
- * E-mail:
| | - Erik W. Debler
- Laboratory of Cell Biology, The Rockefeller University, New York, New York, United States of America
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55
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Stulemeijer IJE, De Vos D, van Harten K, Joshi OK, Blomberg O, van Welsem T, Terweij M, Vlaming H, de Graaf EL, Altelaar AFM, Bakker BM, van Leeuwen F. Dot1 histone methyltransferases share a distributive mechanism but have highly diverged catalytic properties. Sci Rep 2015; 5:9824. [PMID: 25965993 PMCID: PMC4650758 DOI: 10.1038/srep09824] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/19/2015] [Indexed: 11/17/2022] Open
Abstract
The conserved histone methyltransferase Dot1 establishes an H3K79 methylation pattern
consisting of mono-, di- and trimethylation states on histone H3 via a distributive
mechanism. This mechanism has been shown to be important for the regulation of the
different H3K79 methylation states in yeast. Dot1 enzymes in yeast, Trypanosoma
brucei (TbDot1A and TbDot1B, which methylate H3K76) and human (hDot1L)
generate very divergent methylation patterns. To understand how these
species-specific methylation patterns are generated, the methylation output of the
Dot1 enzymes was compared by expressing them in yeast at various expression levels.
Computational simulations based on these data showed that the Dot1 enzymes have
highly distinct catalytic properties, but share a distributive mechanism. The
mechanism of methylation and the distinct rate constants have implications for the
regulation of H3K79/K76 methylation. A mathematical model of H3K76 methylation
during the trypanosome cell cycle suggests that temporally-regulated consecutive
action of TbDot1A and TbDot1B is required for the observed regulation of H3K76
methylation states.
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Affiliation(s)
- Iris J E Stulemeijer
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Dirk De Vos
- Department of Biology, University of Antwerp, Antwerp, 2020, Belgium
| | - Kirsten van Harten
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Onkar K Joshi
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Olga Blomberg
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Tibor van Welsem
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Marit Terweij
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Hanneke Vlaming
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
| | - Erik L de Graaf
- Biomolecular Mass Spectrometry and Proteomics Group, The Netherlands Proteomics Centre, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - A F Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics Group, The Netherlands Proteomics Centre, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Barbara M Bakker
- Department of Pediatrics, Systems Biology Centre for Energy Metabolism and Ageing, Center for Liver, Digestive and Metabolic Diseases, University of Groningen, University Medical Center Groningen, Groningen, 9713 GZ, The Netherlands
| | - Fred van Leeuwen
- Division of Gene Regulation, Netherlands Cancer Institute, Amsterdam, 1066 CX, The Netherlands
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56
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Ramey-Butler K, Ullu E, Kolev NG, Tschudi C. Synchronous expression of individual metacyclic variant surface glycoprotein genes in Trypanosoma brucei. Mol Biochem Parasitol 2015; 200:1-4. [PMID: 25896436 DOI: 10.1016/j.molbiopara.2015.04.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 04/03/2015] [Accepted: 04/08/2015] [Indexed: 11/27/2022]
Abstract
One distinctive feature of the Trypanosoma brucei life cycle is the presence of two discrete populations that are based on differential expression of variant surface glycoproteins (VSGs). Both are adapted to the environmental pressures they face and more importantly, both contribute directly to transmission. Metacyclics in the tsetse fly enable transmission to a new mammalian host, whereas bloodstream trypanosomes must avoid immune destruction to the extent that sufficient numbers are available for transmission, when the insect vector takes a blood meal. At present, there are few investigations on the molecular aspects of parasite biology in the tsetse vector and specifically about the activation of metacyclic VSG gene expression. Here we used an established in vitro differentiation system based on the overexpression of the RNA-binding protein 6 (RBP6), to monitor two metacyclic VSGs (VSG 397 and VSG 653) during development from procyclics to infectious metacyclic forms. We observed that activation of these two mVSGs was simultaneous both at the transcript and protein level, and manifested by the appearance of only one of the mVSGs in individual cells.
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Affiliation(s)
- Kiantra Ramey-Butler
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06536, USA
| | - Elisabetta Ullu
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06536, USA; Department of Cell Biology, Yale School of Medicine, New Haven, CT 06536, USA
| | - Nikolay G Kolev
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06536, USA.
| | - Christian Tschudi
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06536, USA
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57
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Mony BM, Matthews KR. Assembling the components of the quorum sensing pathway in African trypanosomes. Mol Microbiol 2015; 96:220-32. [PMID: 25630552 PMCID: PMC4403954 DOI: 10.1111/mmi.12949] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2015] [Indexed: 12/14/2022]
Abstract
African trypanosomes, parasites that cause human sleeping sickness, undergo a density-dependent differentiation in the bloodstream of their mammalian hosts. This process is driven by a released parasite-derived factor that causes parasites to accumulate in G1 and become quiescent. This is accompanied by morphological transformation to 'stumpy' forms that are adapted to survival and further development when taken up in the blood meal of tsetse flies, the vector for trypanosomiasis. Although the soluble signal driving differentiation to stumpy forms is unidentified, a recent genome-wide RNAi screen identified many of the intracellular signalling and effector molecules required for the response to this signal. These resemble components of nutritional starvation and quiescence pathways in other eukaryotes, suggesting that parasite development shares similarities with the adaptive quiescence of organisms such as yeasts and Dictyostelium in response to nutritional starvation and stress. Here, the trypanosome signalling pathway is discussed in the context of these conserved pathways and the possible contributions of opposing 'slender retainer' and 'stumpy inducer' arms described. As evolutionarily highly divergent eukaryotes, the organisation and conservation of this developmental pathway can provide insight into the developmental cycle of other protozoan parasites, as well as the adaptive and programmed developmental responses of all eukaryotic cells.
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Affiliation(s)
- Binny M Mony
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of EdinburghCharlotte Auerbach Road, Edinburgh, EH9 3FL, UK
| | - Keith R Matthews
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of EdinburghCharlotte Auerbach Road, Edinburgh, EH9 3FL, UK
- *For correspondence. E-mail ; Tel. (+44) 131 651 3639; Fax (+44) 131 651 3670
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58
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Matthews KR. 25 years of African trypanosome research: From description to molecular dissection and new drug discovery. Mol Biochem Parasitol 2015; 200:30-40. [PMID: 25736427 PMCID: PMC4509711 DOI: 10.1016/j.molbiopara.2015.01.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/09/2015] [Accepted: 01/13/2015] [Indexed: 01/27/2023]
Abstract
The Molecular Parasitology conference was first held at the Marine Biological laboratory, Woods Hole, USA 25 years ago. Since that first meeting, the conference has evolved and expanded but has remained the showcase for the latest research developments in molecular parasitology. In this perspective, I reflect on the scientific discoveries focussed on African trypanosomes (Trypanosoma brucei spp.) that have occurred since the inaugural MPM meeting and discuss the current and future status of research on these parasites.
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Affiliation(s)
- Keith R Matthews
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK.
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59
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DNA double-strand breaks and telomeres play important roles in trypanosoma brucei antigenic variation. EUKARYOTIC CELL 2015; 14:196-205. [PMID: 25576484 DOI: 10.1128/ec.00207-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Human-infecting microbial pathogens all face a serious problem of elimination by the host immune response. Antigenic variation is an effective immune evasion mechanism where the pathogen regularly switches its major surface antigen. In many cases, the major surface antigen is encoded by genes from the same gene family, and its expression is strictly monoallelic. Among pathogens that undergo antigenic variation, Trypanosoma brucei (a kinetoplastid), which causes human African trypanosomiasis, Plasmodium falciparum (an apicomplexan), which causes malaria, Pneumocystis jirovecii (a fungus), which causes pneumonia, and Borrelia burgdorferi (a bacterium), which causes Lyme disease, also express their major surface antigens from loci next to the telomere. Except for Plasmodium, DNA recombination-mediated gene conversion is a major pathway for surface antigen switching in these pathogens. In the last decade, more sophisticated molecular and genetic tools have been developed in T. brucei, and our knowledge of functions of DNA recombination in antigenic variation has been greatly advanced. VSG is the major surface antigen in T. brucei. In subtelomeric VSG expression sites (ESs), VSG genes invariably are flanked by a long stretch of upstream 70-bp repeats. Recent studies have shown that DNA double-strand breaks (DSBs), particularly those in 70-bp repeats in the active ES, are a natural potent trigger for antigenic variation in T. brucei. In addition, telomere proteins can influence VSG switching by reducing the DSB amount at subtelomeric regions. These findings will be summarized and their implications will be discussed in this review.
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60
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Mono-allelic VSG expression by RNA polymerase I in Trypanosoma brucei: expression site control from both ends? Gene 2014; 556:68-73. [PMID: 25261847 DOI: 10.1016/j.gene.2014.09.047] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 02/01/2023]
Abstract
Trypanosoma brucei is a vector borne, lethal protistan parasite of humans and livestock in sub-Saharan Africa. Antigenic variation of its cell surface coat enables the parasite to evade adaptive immune responses and to live freely in the blood of its mammalian hosts. The coat consists of ten million copies of variant surface glycoprotein (VSG) that is expressed from a single VSG gene, drawn from a large repertoire and located near the telomere at one of fifteen so-called bloodstream expression sites (BESs). Thus, antigenic variation is achieved by switching to the expression of a different VSG gene. A BES is a tandem array of expression site-associated genes and a terminal VSG gene. It is polycistronically transcribed by a multifunctional RNA polymerase I (RNAPI) from a short promoter that is located 45-60 kb upstream of the VSG gene. The mechanism(s) restricting VSG expression to a single BES are not well understood. There is convincing evidence that epigenetic silencing and transcription attenuation play important roles. Furthermore, recent data indicated that there is regulation at the level of transcription initiation and that, surprisingly, the VSG mRNA appears to have a role in restricting VSG expression to a single gene. Here, we review BES expression regulation and propose a model in which telomere-directed, epigenetic BES silencing is opposed by BES promoter-directed, activated RNAPI transcription.
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61
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Ooi CP, Rudenko G. Do trypanosome turncoats wait before they commit? eLife 2014; 3:e03176. [PMID: 24894466 PMCID: PMC4042340 DOI: 10.7554/elife.03176] [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] [Indexed: 11/13/2022] Open
Abstract
The strategy that sleeping sickness parasites use to evade the mammalian immune system may be linked to the metamorphosis that allows them to transfer from mammals into tsetse flies.
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Affiliation(s)
- Cher-Pheng Ooi
- Cher-Pheng Ooi is in the Division of Cell and Molecular Biology, Imperial College London, London, United Kingdom
| | - Gloria Rudenko
- Gloria Rudenko is in the Division of Cell and Molecular Biology, Imperial College London, London, United Kingdom
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