51
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Klug D, Kehrer J, Frischknecht F, Singer M. A synthetic promoter for multi-stage expression to probe complementary functions of Plasmodium adhesins. J Cell Sci 2018; 131:jcs.210971. [PMID: 30237220 DOI: 10.1242/jcs.210971] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 09/10/2018] [Indexed: 11/20/2022] Open
Abstract
Gene expression of malaria parasites is mediated by the apicomplexan Apetala2 (ApiAP2) transcription factor family. Different ApiAP2s control gene expression at distinct stages in the complex life cycle of the parasite, ensuring timely expression of stage-specific genes. ApiAP2s recognize short cis-regulatory elements that are enriched in the upstream/promoter region of their target genes. This should, in principle, allow the generation of 'synthetic' promoters that drive gene expression at desired stages of the Plasmodium life cycle. Here we test this concept by combining cis-regulatory elements of two genes expressed successively within the mosquito part of the life cycle. Our tailored 'synthetic' promoters, named Spooki 1.0 and Spooki 2.0, activate gene expression in early and late mosquito stages, as shown by the expression of a fluorescent reporter. We used these promoters to address the specific functionality of two related adhesins that are exclusively expressed either during the early or late mosquito stage. By modifying the expression profile of both adhesins in absence of their counterpart we were able to test for complementary functions in gliding and invasion. We discuss the possible advantages and drawbacks of our approach.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Dennis Klug
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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52
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Batugedara G, Le Roch KG. Unraveling the 3D genome of human malaria parasites. Semin Cell Dev Biol 2018; 90:144-153. [PMID: 30009946 DOI: 10.1016/j.semcdb.2018.07.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 07/03/2018] [Indexed: 01/31/2023]
Abstract
The chromosomes within the eukaryotic cell nucleus are highly dynamic and adopt complex hierarchical structures. Understanding how this three-dimensional (3D) nuclear architectureaffects gene regulation, cell cycle progression and disease pathogenesis are important biological questions in development and disease. Recently, many genome-wide technologies including chromosome conformation capture (3C) and 3C-based methodologies (4C, 5C, and Hi-C) have been developed to investigate 3D chromatin structure. In this review, we introduce 3D genome methodologies, with a focus on their application for understanding the nuclear architecture of the human malaria parasite, Plasmodium falciparum. An increasing amount of evidence now suggests that gene regulation in the parasite is largely regulated by epigenetic mechanisms and nuclear reorganization. Here, we explore the 3D genome architecture of P. falciparum, including local and global chromatin structure. In addition, molecular components important for maintaining 3D chromatin organization including architectural proteins and long non-coding RNAs are discussed. Collectively, these studies contribute to our understanding of how the plasticity of 3D genome architecture regulates gene expression and cell cycle progression in this deadly parasite.
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Affiliation(s)
- Gayani Batugedara
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Karine G Le Roch
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA.
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53
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Josling GA, Williamson KC, Llinás M. Regulation of Sexual Commitment and Gametocytogenesis in Malaria Parasites. Annu Rev Microbiol 2018; 72:501-519. [PMID: 29975590 DOI: 10.1146/annurev-micro-090817-062712] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Sexual differentiation of malaria parasites from the asexual blood stage into gametocytes is an essential part of the life cycle, as gametocytes are the form that is taken up by the mosquito host. Because of the essentiality of this process for transmission to the mosquito, gametocytogenesis is an extremely attractive target for therapeutic interventions. The subject of this review is the considerable progress that has been made in recent years in elucidating the molecular mechanisms governing this important differentiation process. In particular, a number of critical transcription factors and epigenetic regulators have emerged as crucial elements in the regulation of commitment. The identification of these factors has allowed us to understand better than ever before the events occurring prior to and during commitment to sexual development and offers potential for new therapeutic interventions.
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Affiliation(s)
- Gabrielle A Josling
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA; .,Huck Center for Malaria Research, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Kim C Williamson
- Microbiology and Immunology Department, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA; .,Huck Center for Malaria Research, Pennsylvania State University, University Park, Pennsylvania 16802, USA.,Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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54
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Lesage KM, Huot L, Mouveaux T, Courjol F, Saliou JM, Gissot M. Cooperative binding of ApiAP2 transcription factors is crucial for the expression of virulence genes in Toxoplasma gondii. Nucleic Acids Res 2018; 46:6057-6068. [PMID: 29788176 PMCID: PMC6159514 DOI: 10.1093/nar/gky373] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 04/27/2018] [Indexed: 01/28/2023] Open
Affiliation(s)
- Kevin M Lesage
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
| | - Ludovic Huot
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
| | - Thomas Mouveaux
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
| | - Flavie Courjol
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
| | - Jean-Michel Saliou
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
| | - Mathieu Gissot
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 8204—CIIL—Centre d’Infection et d’Immunité de Lille, F-59000 Lille, France
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55
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Radke JB, Worth D, Hong D, Huang S, Sullivan WJ, Wilson EH, White MW. Transcriptional repression by ApiAP2 factors is central to chronic toxoplasmosis. PLoS Pathog 2018; 14:e1007035. [PMID: 29718996 PMCID: PMC5951591 DOI: 10.1371/journal.ppat.1007035] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 05/14/2018] [Accepted: 04/17/2018] [Indexed: 12/20/2022] Open
Abstract
Tachyzoite to bradyzoite development in Toxoplasma is marked by major changes in gene expression resulting in a parasite that expresses a new repertoire of surface antigens hidden inside a modified parasitophorous vacuole called the tissue cyst. The factors that control this important life cycle transition are not well understood. Here we describe an important transcriptional repressor mechanism controlling bradyzoite differentiation that operates in the tachyzoite stage. The ApiAP2 factor, AP2IV-4, is a nuclear factor dynamically expressed in late S phase through mitosis/cytokinesis of the tachyzoite cell cycle. Remarkably, deletion of the AP2IV-4 locus resulted in the expression of a subset of bradyzoite-specific proteins in replicating tachyzoites that included tissue cyst wall components BPK1, MCP4, CST1 and the surface antigen SRS9. In the murine animal model, the mis-timing of bradyzoite antigens in tachyzoites lacking AP2IV-4 caused a potent inflammatory monocyte immune response that effectively eliminated this parasite and prevented tissue cyst formation in mouse brain tissue. Altogether, these results indicate that suppression of bradyzoite antigens by AP2IV-4 during acute infection is required for Toxoplasma to successfully establish a chronic infection in the immune-competent host. The Toxoplasma biology that underlies the establishment of a chronic infection is developmental conversion of the acute tachyzoite stage into the latent bradyzoite-tissue cyst stage. Despite the important clinical consequences of this developmental pathway, the molecular basis of the switch mechanisms that control formation of the tissue cyst is still poorly understood. A fundamental feature of tissue cyst formation is the expression of bradyzoite-specific genes. Here we show the transcription factor AP2IV-4 directly silences bradyzoite mRNA and protein expression in the acute tachyzoite stage demonstrating that developmental control of tissue cyst formation is as much about when not to express bradyzoite genes as it is about when to activate them. Losing the suppression of bradyzoite gene expression in the acute tachyzoite stage caused by deleting AP2IV-4 blocked the establishment of chronic disease in healthy animals via increased protective immunity suggesting a possible strategy for preventing chronic Toxoplasma infections.
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Affiliation(s)
- Joshua B. Radke
- Department of Global Health, University of South Florida, Tampa, FL, United States of America
| | - Danielle Worth
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States of America
| | - David Hong
- Department of Global Health, University of South Florida, Tampa, FL, United States of America
| | - Sherri Huang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - William J. Sullivan
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Emma H. Wilson
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States of America
| | - Michael W. White
- Department of Global Health, University of South Florida, Tampa, FL, United States of America
- * E-mail:
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56
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Lippuner C, Ramakrishnan C, Basso WU, Schmid MW, Okoniewski M, Smith NC, Hässig M, Deplazes P, Hehl AB. RNA-Seq analysis during the life cycle of Cryptosporidium parvum reveals significant differential gene expression between proliferating stages in the intestine and infectious sporozoites. Int J Parasitol 2018; 48:413-422. [DOI: 10.1016/j.ijpara.2017.10.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/06/2017] [Accepted: 10/21/2017] [Indexed: 10/18/2022]
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57
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Toenhake CG, Fraschka SAK, Vijayabaskar MS, Westhead DR, van Heeringen SJ, Bártfai R. Chromatin Accessibility-Based Characterization of the Gene Regulatory Network Underlying Plasmodium falciparum Blood-Stage Development. Cell Host Microbe 2018; 23:557-569.e9. [PMID: 29649445 PMCID: PMC5899830 DOI: 10.1016/j.chom.2018.03.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 02/05/2018] [Accepted: 03/05/2018] [Indexed: 02/07/2023]
Abstract
Underlying the development of malaria parasites within erythrocytes and the resulting pathogenicity is a hardwired program that secures proper timing of gene transcription and production of functionally relevant proteins. How stage-specific gene expression is orchestrated in vivo remains unclear. Here, using the assay for transposase accessible chromatin sequencing (ATAC-seq), we identified ∼4,000 regulatory regions in P. falciparum intraerythrocytic stages. The vast majority of these sites are located within 2 kb upstream of transcribed genes and their chromatin accessibility pattern correlates positively with abundance of the respective mRNA transcript. Importantly, these regions are sufficient to drive stage-specific reporter gene expression and DNA motifs enriched in stage-specific sets of regulatory regions interact with members of the P. falciparum AP2 transcription factor family. Collectively, this study provides initial insights into the in vivo gene regulatory network of P. falciparum intraerythrocytic stages and should serve as a valuable resource for future studies.
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Affiliation(s)
- Christa Geeke Toenhake
- Radboud University, Faculty of Science, Department of Molecular Biology, Nijmegen, 6525 GA, the Netherlands
| | | | | | - David Robert Westhead
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Simon Jan van Heeringen
- Radboud University, Faculty of Science, Department of Molecular Developmental Biology, Nijmegen, 6525 GA, the Netherlands
| | - Richárd Bártfai
- Radboud University, Faculty of Science, Department of Molecular Biology, Nijmegen, 6525 GA, the Netherlands.
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58
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Gural N, Mancio-Silva L, Miller AB, Galstian A, Butty VL, Levine SS, Patrapuvich R, Desai SP, Mikolajczak SA, Kappe SHI, Fleming HE, March S, Sattabongkot J, Bhatia SN. In Vitro Culture, Drug Sensitivity, and Transcriptome of Plasmodium Vivax Hypnozoites. Cell Host Microbe 2018; 23:395-406.e4. [PMID: 29478773 DOI: 10.1016/j.chom.2018.01.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/21/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
Abstract
The unique relapsing nature of Plasmodium vivax infection is a major barrier to malaria eradication. Upon infection, dormant liver-stage forms, hypnozoites, linger for weeks to months and then relapse to cause recurrent blood-stage infection. Very little is known about hypnozoite biology; definitive biomarkers are lacking and in vitro platforms that support phenotypic studies are needed. Here, we recapitulate the entire liver stage of P. vivax in vitro, using a multiwell format that incorporates micropatterned primary human hepatocyte co-cultures (MPCCs). MPCCs feature key aspects of P. vivax biology, including establishment of persistent small forms and growing schizonts, merosome release, and subsequent infection of reticulocytes. We find that the small forms exhibit previously described hallmarks of hypnozoites, and we pilot MPCCs as a tool for testing candidate anti-hypnozoite drugs. Finally, we employ a hybrid capture strategy and RNA sequencing to describe the hypnozoite transcriptome and gain insight into its biology.
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Affiliation(s)
- Nil Gural
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Boston, MA 02142, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA
| | - Liliana Mancio-Silva
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Boston, MA 02142, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA
| | - Alex B Miller
- Broad Institute, Boston, MA 02142, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA
| | | | - Vincent L Butty
- BioMicro Center, Massachusetts Institute of Technology, Boston, MA 02142, USA
| | - Stuart S Levine
- BioMicro Center, Massachusetts Institute of Technology, Boston, MA 02142, USA
| | - Rapatbhorn Patrapuvich
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine Mahidol University, Bangkok 10400, Thailand
| | | | | | | | - Heather E Fleming
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Boston, MA 02142, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA
| | - Sandra March
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Boston, MA 02142, USA; Broad Institute, Boston, MA 02142, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine Mahidol University, Bangkok 10400, Thailand
| | - Sangeeta N Bhatia
- Harvard-MIT Department of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Boston, MA 02142, USA; Broad Institute, Boston, MA 02142, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA; Koch Institute for Integrative Cancer Research, Boston, MA 02142, USA; Department of Medicine, Brigham and Women's Hospital Boston, Boston, MA 02115, USA.
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59
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Systematic CRISPR-Cas9-Mediated Modifications of Plasmodium yoelii ApiAP2 Genes Reveal Functional Insights into Parasite Development. mBio 2017; 8:mBio.01986-17. [PMID: 29233900 PMCID: PMC5727417 DOI: 10.1128/mbio.01986-17] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Malaria parasites have a complex life cycle with multiple developmental stages in mosquito and vertebrate hosts, and different developmental stages express unique sets of genes. Unexpectedly, many transcription factors (TFs) commonly found in eukaryotic organisms are absent in malaria parasites; instead, a family of genes encoding proteins similar to the plant Apetala2 (ApiAP2) transcription factors is expanded in the parasites. Several malaria ApiAP2 genes have been shown to play a critical role in parasite development; however, the functions of the majority of the ApiAP2 genes remain to be elucidated. In particular, no study on the Plasmodium yoelii ApiAP2 (PyApiAP2) gene family has been reported so far. This study systematically investigated the functional roles of PyApiAP2 genes in parasite development. Twenty-four of the 26 PyApiAP2 genes were selected for disruption, and 12 were successfully knocked out using the clustered regularly interspaced short palindromic repeat–CRISPR-associated protein 9 (CRISPR-Cas9) method. The effects of gene knockout (KO) on parasite development in mouse and mosquito stages were evaluated. Ten of 12 successfully disrupted genes, including two genes that have not been functionally characterized in any Plasmodium species previously, were shown to be critical for P. yoelii development of sexual and mosquito stages. Additionally, seven of the genes were labeled for protein expression analysis, revealing important information supporting their functions. This study represents the first systematic functional characterization of the P. yoelii ApiAP2 gene family and discovers important insights on the roles of the ApiAP2 genes in parasite development. Malaria is a parasitic disease that infects hundreds of millions of people, leading to an estimated 0.35 million deaths in 2015. A better understanding of the mechanism of gene expression regulation during parasite development may provide important clues for disease control and prevention. In this study, systematic gene disruption experiments were performed to study the functional roles of members of the Plasmodium yoelii ApiAP2 (PyApiAP2) gene family in parasite development. Genes that are critical for the development of male and female gametocytes, oocysts, and sporozoites were characterized. The protein expression profiles for seven of the PyApiAP2 gene products were also analyzed, revealing important information on their functions. This study provides expression and functional information for many PyApiAP2 genes, which can be explored for disease management.
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60
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Lima WR, Martins DC, Parreira KS, Scarpelli P, Santos de Moraes M, Topalis P, Hashimoto RF, Garcia CRS. Genome-wide analysis of the human malaria parasite Plasmodium falciparum transcription factor PfNF-YB shows interaction with a CCAAT motif. Oncotarget 2017; 8:113987-114001. [PMID: 29371963 PMCID: PMC5768380 DOI: 10.18632/oncotarget.23053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 11/26/2017] [Indexed: 12/04/2022] Open
Abstract
Little is known about transcription factor regulation during the Plasmodium falciparum intraerythrocytic cycle. In order to elucidate the role of the P. falciparum (Pf)NF-YB transcription factor we searched for target genes in the entire genome. PfNF-YB mRNA is highly expressed in late trophozoite and schizont stages relative to the ring stage. In order to determine the candidate genes bound by PfNF-YB a ChIP-on-chip assay was carried out and 297 genes were identified. Ninety nine percent of PfNF-YB binding was to putative promoter regions of protein coding genes of which only 16% comprise proteins of known function. Interestingly, our data reveal that PfNF-YB binding is not exclusively to a canonical CCAAT box motif. PfNF-YB binds to genes coding for proteins implicated in a range of different biological functions, such as replication protein A large subunit (DNA replication), hypoxanthine phosphoribosyltransferase (nucleic acid metabolism) and multidrug resistance protein 2 (intracellular transport).
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Affiliation(s)
- Wânia Rezende Lima
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.,Instituto de Ciências Exatas e Naturais-Medicina, Universidade Federal de Mato Grosso-Campus Rondonópolis, Mato Grosso, Brazil
| | - David Correa Martins
- Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, Brazil
| | - Kleber Simônio Parreira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Instituto de Ciências Exatas e Naturais-Medicina, Universidade Federal de Mato Grosso-Campus Rondonópolis, Mato Grosso, Brazil
| | - Pedro Scarpelli
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Miriam Santos de Moraes
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Pantelis Topalis
- Institute of Molecular Biology and Biotechnology, FORTH, Hellas, Greece
| | - Ronaldo Fumio Hashimoto
- Departamento de Ciência da Computação, Instituto de Matemática e Estatística, Universidade de São Paulo, São Paulo, Brazil
| | - Célia R S Garcia
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
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61
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Yakubu RR, Weiss LM, Silmon de Monerri NC. Post-translational modifications as key regulators of apicomplexan biology: insights from proteome-wide studies. Mol Microbiol 2017; 107:1-23. [PMID: 29052917 DOI: 10.1111/mmi.13867] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/12/2017] [Accepted: 10/16/2017] [Indexed: 12/12/2022]
Abstract
Parasites of the Apicomplexa phylum, such as Plasmodium spp. and Toxoplasma gondii, undergo complex life cycles involving multiple stages with distinct biology and morphologies. Post-translational modifications (PTMs), such as phosphorylation, acetylation and glycosylation, regulate numerous cellular processes, playing a role in every aspect of cell biology. PTMs can occur on proteins at any time in their lifespan and through alterations of target protein activity, localization, protein-protein interactions, among other functions, dramatically increase proteome diversity and complexity. In addition, PTMs can be induced or removed on changes in cellular environment and state. Thus, PTMs are likely to be key regulators of developmental transitions, biology and pathogenesis of apicomplexan parasites. In this review we examine the roles of PTMs in both parasite-specific and conserved eukaryotic processes, and the potential crosstalk between PTMs, that together regulate the intricate lives of these protozoa.
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Affiliation(s)
- Rama R Yakubu
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA.,Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA
| | - Louis M Weiss
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA.,Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA
| | - Natalie C Silmon de Monerri
- Department of Pathology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA.,Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY, 10128, USA
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62
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Martins RM, Macpherson CR, Claes A, Scheidig-Benatar C, Sakamoto H, Yam XY, Preiser P, Goel S, Wahlgren M, Sismeiro O, Coppée JY, Scherf A. An ApiAP2 member regulates expression of clonally variant genes of the human malaria parasite Plasmodium falciparum. Sci Rep 2017; 7:14042. [PMID: 29070841 PMCID: PMC5656681 DOI: 10.1038/s41598-017-12578-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 06/09/2017] [Indexed: 02/02/2023] Open
Abstract
Variegated surface antigen expression is key to chronic infection and pathogenesis of the human malaria parasite Plasmodium falciparum. This protozoan parasite expresses distinct surface molecules that are encoded by clonally variant gene families such as var, rif and stevor. The molecular mechanisms governing activation of individual members remain ill-defined. To investigate the molecular events of the initial transcriptional activation process we focused on a member of the apicomplexan ApiAP2 transcription factor family predicted to bind to the 5′ upstream regions of the var gene family, AP2-exp (PF3D7_1466400). Viable AP2-exp mutant parasites rely on expressing no less than a short truncated protein including the N-terminal AP2 DNA-binding domain. RNA-seq analysis in mutant parasites revealed transcriptional changes in a subset of exported proteins encoded by clonally variant gene families. Upregulation of RIFINs and STEVORs was validated at the protein levels. In addition, morphological alterations were observed on the surface of the host cells infected by the mutants. This work points to a complex regulatory network of clonally variant gene families in which transcription of a subset of members is regulated by the same transcription factor. In addition, we highlight the importance of the non-DNA binding AP2 domain in functional gene regulation.
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Affiliation(s)
- Rafael M Martins
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France. .,CNRS, ERL 9195, Paris, 75015, France. .,INSERM, Unit U1201, Paris, 75015, France. .,CNRS 5290/IRD 224/University of Montpellier ("MiVEGEC"), Montpellier, France.
| | - Cameron R Macpherson
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France.,CNRS, ERL 9195, Paris, 75015, France.,INSERM, Unit U1201, Paris, 75015, France
| | - Aurélie Claes
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France.,CNRS, ERL 9195, Paris, 75015, France.,INSERM, Unit U1201, Paris, 75015, France
| | - Christine Scheidig-Benatar
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France.,CNRS, ERL 9195, Paris, 75015, France.,INSERM, Unit U1201, Paris, 75015, France
| | - Hiroshi Sakamoto
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France.,CNRS, ERL 9195, Paris, 75015, France.,INSERM, Unit U1201, Paris, 75015, France
| | - Xue Yan Yam
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Peter Preiser
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Suchi Goel
- MTC, Nobels väg 16, KI Solna Campus Karolinska Institutet, Box 280, SE-171 77, Stockholm, Sweden.,Institute of Science Education and Research (IISER), Tirupati Rami Reddy Nagar, 517507, Mangalam, Tirupati Andhra Pradhesh, India
| | - Mats Wahlgren
- MTC, Nobels väg 16, KI Solna Campus Karolinska Institutet, Box 280, SE-171 77, Stockholm, Sweden
| | - Odile Sismeiro
- Plateforme 2, Transcriptome et Epigenome, Institut Pasteur, Paris, 75015, France
| | - Jean-Yves Coppée
- Plateforme 2, Transcriptome et Epigenome, Institut Pasteur, Paris, 75015, France
| | - Artur Scherf
- Unité Biologie des Interactions Hôte-Parasite, Institut Pasteur, Paris, 75015, France. .,CNRS, ERL 9195, Paris, 75015, France. .,INSERM, Unit U1201, Paris, 75015, France.
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63
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Translational Control in the Latency of Apicomplexan Parasites. Trends Parasitol 2017; 33:947-960. [PMID: 28942109 DOI: 10.1016/j.pt.2017.08.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/08/2017] [Accepted: 08/14/2017] [Indexed: 01/07/2023]
Abstract
Apicomplexan parasites Toxoplasma gondii and Plasmodium spp. use latent stages to persist in the host, facilitate transmission, and thwart treatment of infected patients. Therefore, it is important to understand the processes driving parasite differentiation to and from quiescent stages. Here, we discuss how a family of protein kinases that phosphorylate the eukaryotic initiation factor-2 (eIF2) function in translational control and drive differentiation. This translational control culminates in reprogramming of the transcriptome to facilitate parasite transition towards latency. We also discuss how eIF2 phosphorylation contributes to the maintenance of latency and provides a crucial role in the timing of reactivation of latent parasites towards proliferative stages.
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64
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A Knockout Screen of ApiAP2 Genes Reveals Networks of Interacting Transcriptional Regulators Controlling the Plasmodium Life Cycle. Cell Host Microbe 2017; 21:11-22. [PMID: 28081440 PMCID: PMC5241200 DOI: 10.1016/j.chom.2016.12.003] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 08/17/2016] [Accepted: 11/17/2016] [Indexed: 01/17/2023]
Abstract
A family of apicomplexa-specific proteins containing AP2 DNA-binding domains (ApiAP2s) was identified in malaria parasites. This family includes sequence-specific transcription factors that are key regulators of development. However, functions for the majority of ApiAP2 genes remain unknown. Here, a systematic knockout screen in Plasmodium berghei identified ten ApiAP2 genes that were essential for mosquito transmission: four were critical for the formation of infectious ookinetes, and three were required for sporogony. We describe non-essential functions for AP2-O and AP2-SP proteins in blood stages, and identify AP2-G2 as a repressor active in both asexual and sexual stages. Comparative transcriptomics across mutants and developmental stages revealed clusters of co-regulated genes with shared cis promoter elements, whose expression can be controlled positively or negatively by different ApiAP2 factors. We propose that stage-specific interactions between ApiAP2 proteins on partly overlapping sets of target genes generate the complex transcriptional network that controls the Plasmodium life cycle. Mutants in 11 of 26 apiAP2 genes reveal gene functions in mosquito transmission Co-expression clustering across mutants and stages reveals molecular phenotypes Multifunctional apiAP2 genes create complex regulatory networks in Plasmodium Ap2-g2 is a transcriptional repressor in both asexual and sexual blood stages
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65
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Sierra-Miranda M, Vembar SS, Delgadillo DM, Ávila-López PA, Herrera-Solorio AM, Lozano Amado D, Vargas M, Hernandez-Rivas R. PfAP2Tel, harbouring a non-canonical DNA-binding AP2 domain, binds to Plasmodium falciparum telomeres. Cell Microbiol 2017; 19. [PMID: 28376558 DOI: 10.1111/cmi.12742] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 03/18/2017] [Accepted: 03/21/2017] [Indexed: 12/11/2022]
Abstract
The telomeres of the malaria parasite Plasmodium falciparum are essential not only for chromosome end maintenance during blood stage development in humans but also to generate genetic diversity by facilitating homologous recombination of subtelomeric, multigene virulence families such as var and rifin. However, other than the telomerase PfTERT, proteins that act at P. falciparum telomeres are poorly characterised. To isolate components that bind to telomeres, we performed oligonucleotide pulldowns and electromobility shift assays with a telomeric DNA probe and identified a non-canonical member of the ApiAP2 family of transcription factors, PfAP2Tel (encoded by PF3D7_0622900), as a component of the P. falciparum telomere-binding protein complex. PfAP2Tel is expressed throughout the intra-erythrocytic life cycle and localises to the nuclear periphery, co-localising with telomeric clusters. Furthermore, EMSAs using the recombinant protein demonstrated direct binding of PfAP2Tel to telomeric repeats in vitro, while genome-wide chromatin immunoprecipitation followed by next generation sequencing corroborated the high specificity of this protein to telomeric ends of all 14 chromosomes in vivo. Taken together, our data describe a novel function for ApiAP2 proteins at chromosome ends and open new avenues to study the molecular machinery that regulates telomere function in P. falciparum.
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Affiliation(s)
- Miguel Sierra-Miranda
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Shruthi-Sridhar Vembar
- Unité de Biologie des Interactions Hôte-Parasite, CNRS URA 2581, Institut Pasteur Paris, Paris, France.,CNRS ERL9195, Paris, France.,INSERM U1201, Paris, France
| | - Dulce María Delgadillo
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Pedro A Ávila-López
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Abril-Marcela Herrera-Solorio
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Daniela Lozano Amado
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Miguel Vargas
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
| | - Rosaura Hernandez-Rivas
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México, México
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66
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Batugedara G, Lu XM, Bunnik EM, Le Roch KG. The Role of Chromatin Structure in Gene Regulation of the Human Malaria Parasite. Trends Parasitol 2017; 33:364-377. [PMID: 28065669 PMCID: PMC5410391 DOI: 10.1016/j.pt.2016.12.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 11/28/2016] [Accepted: 12/07/2016] [Indexed: 12/11/2022]
Abstract
The human malaria parasite, Plasmodium falciparum, depends on a coordinated regulation of gene expression for development and propagation within the human host. Recent developments suggest that gene regulation in the parasite is largely controlled by epigenetic mechanisms. Here, we discuss recent advancements contributing to our understanding of the mechanisms controlling gene regulation in the parasite, including nucleosome landscape, histone modifications, and nuclear architecture. In addition, various processes involved in regulation of parasite-specific genes and gene families are examined. Finally, we address the use of epigenetic processes as targets for novel antimalarial therapies. Collectively, these topics highlight the unique biology of P. falciparum, and contribute to our understanding of mechanisms regulating gene expression in this deadly parasite.
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Affiliation(s)
- Gayani Batugedara
- Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, CA 92521, USA
| | - Xueqing M Lu
- Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, CA 92521, USA
| | - Evelien M Bunnik
- Department of Microbiology, Immunology & Molecular Genetics, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Karine G Le Roch
- Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, CA 92521, USA.
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Toxoplasma gondii AP2IX-4 Regulates Gene Expression during Bradyzoite Development. mSphere 2017; 2:mSphere00054-17. [PMID: 28317026 PMCID: PMC5352832 DOI: 10.1128/msphere.00054-17] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 02/24/2017] [Indexed: 11/21/2022] Open
Abstract
Toxoplasma gondii is a single-celled parasite that persists in its host as a transmissible tissue cyst. How the parasite converts from its replicative form to the bradyzoites housed in tissue cysts is not well understood, but the process clearly involves changes in gene expression. Here we report that parasites lacking a cell cycle-regulated transcription factor called AP2IX-4 display reduced frequencies of tissue cyst formation in culture and in a mouse model of infection. Parasites missing AP2IX-4 lose the ability to regulate bradyzoite genes during tissue cyst development. Expressed in developing bradyzoites still undergoing division, AP2IX-4 may serve as a useful marker in the study of transitional forms of the parasite. Toxoplasma gondii is a protozoan parasite of great importance to human and animal health. In the host, this obligate intracellular parasite persists as a tissue cyst that is imperceptible to the immune response and unaffected by current therapies. The tissue cysts facilitate transmission through predation and give rise to chronic cycles of toxoplasmosis in immunocompromised patients. Transcriptional changes accompany conversion of the rapidly replicating tachyzoites into the encysted bradyzoites, and yet the mechanisms underlying these alterations in gene expression are not well defined. Here we show that AP2IX-4 is a nuclear protein exclusively expressed in tachyzoites and bradyzoites undergoing division. Knockout of AP2IX-4 had no discernible effect on tachyzoite replication but resulted in a reduced frequency of tissue cyst formation following alkaline stress induction—a defect that is reversible by complementation. AP2IX-4 has a complex role in regulating bradyzoite gene expression, as the levels of many bradyzoite mRNAs dramatically increased beyond those seen under conditions of normal stress induction in AP2IX-4 knockout parasites exposed to alkaline media. The loss of AP2IX-4 also resulted in a modest virulence defect and reduced cyst burden in chronically infected mice, which was reversed by complementation. These findings illustrate that the transcriptional mechanisms responsible for tissue cyst development operate across the intermediate life cycle from the dividing tachyzoite to the dormant bradyzoite. IMPORTANCEToxoplasma gondii is a single-celled parasite that persists in its host as a transmissible tissue cyst. How the parasite converts from its replicative form to the bradyzoites housed in tissue cysts is not well understood, but the process clearly involves changes in gene expression. Here we report that parasites lacking a cell cycle-regulated transcription factor called AP2IX-4 display reduced frequencies of tissue cyst formation in culture and in a mouse model of infection. Parasites missing AP2IX-4 lose the ability to regulate bradyzoite genes during tissue cyst development. Expressed in developing bradyzoites still undergoing division, AP2IX-4 may serve as a useful marker in the study of transitional forms of the parasite.
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68
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Opposing Transcriptional Mechanisms Regulate Toxoplasma Development. mSphere 2017; 2:mSphere00347-16. [PMID: 28251183 PMCID: PMC5322347 DOI: 10.1128/msphere.00347-16] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 02/01/2017] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma infections are lifelong because of the development of the bradyzoite tissue cyst, which is effectively invisible to the immune system. Despite the important clinical consequences of this developmental pathway, the molecular basis of the switch mechanisms that control tissue cyst formation is still poorly understood. Significant changes in gene expression are associated with tissue cyst development, and ApiAP2 transcription factors are an important mechanism regulating this developmental transcriptome. However, the molecular composition of these ApiAP2 complexes and the operating principles of ApiAP2 mechanisms are not well defined. Here we establish that competing ApiAP2 transcriptional mechanisms operate to regulate this clinically important developmental pathway. The Toxoplasma biology that underlies human chronic infection is developmental conversion of the acute tachyzoite stage into the latent bradyzoite stage. We investigated the roles of two alkaline-stress-induced ApiAP2 transcription factors, AP2IV-3 and AP2IX-9, in bradyzoite development. These factors were expressed in two overlapping waves during bradyzoite development, with AP2IX-9 increasing expression earlier than AP2IV-3, which peaked as AP2IX-9 expression was declining. Disruption of the AP2IX-9 gene enhanced, while deletion of AP2IV-3 gene decreased, tissue cyst formation, demonstrating that these factors have opposite functions in bradyzoite development. Conversely, conditional overexpression of FKBP-modified AP2IX-9 or AP2IV-3 with the small molecule Shield 1 had a reciprocal effect on tissue cyst formation, confirming the conclusions of the knockout experiments. The AP2IX-9 repressor and AP2IV-3 activator tissue cyst phenotypes were borne out in gene expression studies that determined that many of the same bradyzoite genes were regulated in an opposite manner by these transcription factors. A common gene target was the canonical bradyzoite marker BAG1, and mechanistic experiments determined that, like AP2IX-9, AP2IV-3 regulates a BAG1 promoter-luciferase reporter and specifically binds the BAG1 promoter in parasite chromatin. Altogether, these results suggest that the AP2IX-9 transcriptional repressor and the AP2IV-3 transcriptional activator likely compete to control bradyzoite gene expression, which may permit Toxoplasma to better adapt to different tissue environments and select a suitable host cell for long-term survival of the dormant tissue cyst. IMPORTANCEToxoplasma infections are lifelong because of the development of the bradyzoite tissue cyst, which is effectively invisible to the immune system. Despite the important clinical consequences of this developmental pathway, the molecular basis of the switch mechanisms that control tissue cyst formation is still poorly understood. Significant changes in gene expression are associated with tissue cyst development, and ApiAP2 transcription factors are an important mechanism regulating this developmental transcriptome. However, the molecular composition of these ApiAP2 complexes and the operating principles of ApiAP2 mechanisms are not well defined. Here we establish that competing ApiAP2 transcriptional mechanisms operate to regulate this clinically important developmental pathway.
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69
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Gómez-Díaz E, Yerbanga RS, Lefèvre T, Cohuet A, Rowley MJ, Ouedraogo JB, Corces VG. Epigenetic regulation of Plasmodium falciparum clonally variant gene expression during development in Anopheles gambiae. Sci Rep 2017; 7:40655. [PMID: 28091569 PMCID: PMC5238449 DOI: 10.1038/srep40655] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 12/09/2016] [Indexed: 12/17/2022] Open
Abstract
P. falciparum phenotypic plasticity is linked to the variant expression of clonal multigene families such as the var genes. We have examined changes in transcription and histone modifications that occur during sporogonic development of P. falciparum in the mosquito host. All var genes are silenced or transcribed at low levels in blood stages (gametocyte/ring) of the parasite in the human host. After infection of mosquitoes, a single var gene is selected for expression in the oocyst, and transcription of this gene increases dramatically in the sporozoite. The same PF3D7_1255200 var gene was activated in 4 different experimental infections. Transcription of this var gene during parasite development in the mosquito correlates with the presence of low levels of H3K9me3 at the binding site for the PF3D7_1466400 AP2 transcription factor. This chromatin state in the sporozoite also correlates with the expression of an antisense long non-coding RNA (lncRNA) that has previously been shown to promote var gene transcription during the intraerythrocytic cycle in vitro. Expression of both the sense protein-coding transcript and the antisense lncRNA increase dramatically in sporozoites. The findings suggest a complex process for the activation of a single particular var gene that involves AP2 transcription factors and lncRNAs.
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70
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Alzan HF, Knowles DP, Suarez CE. Comparative Bioinformatics Analysis of Transcription Factor Genes Indicates Conservation of Key Regulatory Domains among Babesia bovis, Babesia microti, and Theileria equi. PLoS Negl Trop Dis 2016; 10:e0004983. [PMID: 27832060 PMCID: PMC5104403 DOI: 10.1371/journal.pntd.0004983] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Apicomplexa tick-borne hemoparasites, including Babesia bovis, Babesia microti, and Theileria equi are responsible for bovine and human babesiosis and equine theileriosis, respectively. These parasites of vast medical, epidemiological, and economic impact have complex life cycles in their vertebrate and tick hosts. Large gaps in knowledge concerning the mechanisms used by these parasites for gene regulation remain. Regulatory genes coding for DNA binding proteins such as members of the Api-AP2, HMG, and Myb families are known to play crucial roles as transcription factors. Although the repertoire of Api-AP2 has been defined and a HMG gene was previously identified in the B. bovis genome, these regulatory genes have not been described in detail in B. microti and T. equi. In this study, comparative bioinformatics was used to: (i) identify and map genes encoding for these transcription factors among three parasites' genomes; (ii) identify a previously unreported HMG gene in B. microti; (iii) define a repertoire of eight conserved Myb genes; and (iv) identify AP2 correlates among B. bovis and the better-studied Plasmodium parasites. Searching the available transcriptome of B. bovis defined patterns of transcription of these three gene families in B. bovis erythrocyte stage parasites. Sequence comparisons show conservation of functional domains and general architecture in the AP2, Myb, and HMG proteins, which may be significant for the regulation of common critical parasite life cycle transitions in B. bovis, B. microti, and T. equi. A detailed understanding of the role of gene families encoding DNA binding proteins will provide new tools for unraveling regulatory mechanisms involved in B. bovis, B. microti, and T. equi life cycles and environmental adaptive responses and potentially contributes to the development of novel convergent strategies for improved control of babesiosis and equine piroplasmosis.
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Affiliation(s)
- Heba F. Alzan
- Parasitology and Animal Diseases Department, National Research Center, Dokki, Giza, Egypt
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Donald P. Knowles
- Animal Disease Research Unit, Agricultural Research Service, USDA, WSU, Pullman, Washington, United States of America
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Carlos E. Suarez
- Animal Disease Research Unit, Agricultural Research Service, USDA, WSU, Pullman, Washington, United States of America
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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71
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Abstract
Malaria continues to impose a significant disease burden on low- and middle-income countries in the tropics. However, revolutionary progress over the last 3 years in nucleic acid sequencing, reverse genetics, and post-genome analyses has generated step changes in our understanding of malaria parasite (Plasmodium spp.) biology and its interactions with its host and vector. Driven by the availability of vast amounts of genome sequence data from Plasmodium species strains, relevant human populations of different ethnicities, and mosquito vectors, researchers can consider any biological component of the malarial process in isolation or in the interactive setting that is infection. In particular, considerable progress has been made in the area of population genomics, with Plasmodium falciparum serving as a highly relevant model. Such studies have demonstrated that genome evolution under strong selective pressure can be detected. These data, combined with reverse genetics, have enabled the identification of the region of the P. falciparum genome that is under selective pressure and the confirmation of the functionality of the mutations in the kelch13 gene that accompany resistance to the major frontline antimalarial, artemisinin. Furthermore, the central role of epigenetic regulation of gene expression and antigenic variation and developmental fate in P. falciparum is becoming ever clearer. This review summarizes recent exciting discoveries that genome technologies have enabled in malaria research and highlights some of their applications to healthcare. The knowledge gained will help to develop surveillance approaches for the emergence or spread of drug resistance and to identify new targets for the development of antimalarial drugs and perhaps vaccines.
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Affiliation(s)
- Sebastian Kirchner
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - B Joanne Power
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK
| | - Andrew P Waters
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, G12 8TA, UK.
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Lehti-Shiu MD, Panchy N, Wang P, Uygun S, Shiu SH. Diversity, expansion, and evolutionary novelty of plant DNA-binding transcription factor families. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1860:3-20. [PMID: 27522016 DOI: 10.1016/j.bbagrm.2016.08.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/21/2016] [Accepted: 08/06/2016] [Indexed: 12/19/2022]
Abstract
Plant transcription factors (TFs) that interact with specific sequences via DNA-binding domains are crucial for regulating transcriptional initiation and are fundamental to plant development and environmental response. In addition, expansion of TF families has allowed functional divergence of duplicate copies, which has contributed to novel, and in some cases adaptive, traits in plants. Thus, TFs are central to the generation of the diverse plant species that we see today. Major plant agronomic traits, including those relevant to domestication, have also frequently arisen through changes in TF coding sequence or expression patterns. Here our goal is to provide an overview of plant TF evolution by first comparing the diversity of DNA-binding domains and the sizes of these domain families in plants and other eukaryotes. Because TFs are among the most highly expanded gene families in plants, the birth and death process of TFs as well as the mechanisms contributing to their retention are discussed. We also provide recent examples of how TFs have contributed to novel traits that are important in plant evolution and in agriculture.This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks, edited by Dr. Erich Grotewold and Dr. Nathan Springer.
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Affiliation(s)
| | - Nicholas Panchy
- The Genetics Graduate Program, Michigan State University, East Lansing, MI 48824, USA
| | - Peipei Wang
- Department of Plant Biology, East Lansing, MI 48824, USA
| | - Sahra Uygun
- The Genetics Graduate Program, Michigan State University, East Lansing, MI 48824, USA
| | - Shin-Han Shiu
- Department of Plant Biology, East Lansing, MI 48824, USA; The Genetics Graduate Program, Michigan State University, East Lansing, MI 48824, USA.
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73
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Bennink S, Kiesow MJ, Pradel G. The development of malaria parasites in the mosquito midgut. Cell Microbiol 2016; 18:905-18. [PMID: 27111866 PMCID: PMC5089571 DOI: 10.1111/cmi.12604] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/13/2016] [Accepted: 04/20/2016] [Indexed: 01/01/2023]
Abstract
The mosquito midgut stages of malaria parasites are crucial for establishing an infection in the insect vector and to thus ensure further spread of the pathogen. Parasite development in the midgut starts with the activation of the intraerythrocytic gametocytes immediately after take-up and ends with traversal of the midgut epithelium by the invasive ookinetes less than 24 h later. During this time period, the plasmodia undergo two processes of stage conversion, from gametocytes to gametes and from zygotes to ookinetes, both accompanied by dramatic morphological changes. Further, gamete formation requires parasite egress from the enveloping erythrocytes, rendering them vulnerable to the aggressive factors of the insect gut, like components of the human blood meal. The mosquito midgut stages of malaria parasites are unprecedented objects to study a variety of cell biological aspects, including signal perception, cell conversion, parasite/host co-adaptation and immune evasion. This review highlights recent insights into the molecules involved in gametocyte activation and gamete formation as well as in zygote-to-ookinete conversion and ookinete midgut exit; it further discusses factors that can harm the extracellular midgut stages as well as the measures of the parasites to protect themselves from any damage.
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Affiliation(s)
- Sandra Bennink
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Meike J Kiesow
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
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74
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Rao PN, Santos JM, Pain A, Templeton TJ, Mair GR. Translational repression of the cpw-wpc gene family in the malaria parasite Plasmodium. Parasitol Int 2016; 65:463-71. [PMID: 27312996 DOI: 10.1016/j.parint.2016.06.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 06/08/2016] [Accepted: 06/10/2016] [Indexed: 12/22/2022]
Abstract
The technical challenges of working with the sexual stages of the malaria parasite Plasmodium have hindered the characterization of sexual stage antigens in the quest for a successful malaria transmission-blocking vaccine. One such predicted and largely uncharacterized group of sexual stage candidate antigens is the CPW-WPC family of proteins. CPW-WPC proteins are named for a characteristic domain that contains two conserved motifs, CPxxW and WPC. Conserved across Apicomplexa, this family is also present earlier in the Alveolata in the free-living, non-parasitophorous, photosynthetic chromerids, Chromera and Vitrella. In Plasmodium falciparum and Plasmodium berghei blood stage parasites, the transcripts of all nine cpw-wpc genes have been detected in gametocytes. RNA immunoprecipitation followed by reverse transcriptase-PCR reveals all P. berghei cpw-wpc transcripts to be bound by the translational repressors DOZI and CITH, and thus are likely under translational control prior to transmission from the rodent host to the mosquito vector in P. berghei. The GFP tagging of two endogenous P. berghei genes confirmed translational silencing in the gametocyte and translation in ookinetes. By establishing a luciferase transgene assay, we show that the 3' untranslated region of PF3D7_1331400 controls protein expression of this reporter in P. falciparum gametocytes. Our analyses suggest that cpw-wpc genes are translationally silenced in gametocytes across Plasmodium spp. and activated during ookinete formation and thus may have a role in transmission to the mosquito.
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Affiliation(s)
- Pavitra N Rao
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY 10065, USA; Programs in Biochemistry, Cell, and Molecular Biology, Weill Graduate School of Medical Sciences of Cornell University, New York, NY 10065, USA
| | - Jorge M Santos
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Arnab Pain
- Pathogen Genomics Laboratory, Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Jeddah 23955-6900, Saudi Arabia; Global Station for Zoonosis Control, Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, N20 W10 Kita-ku, Sapporo 001-0020, Japan
| | - Thomas J Templeton
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY 10065, USA; Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki 852-8523, Japan.
| | - Gunnar R Mair
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal; Parasitology, Center for Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
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75
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A Plasmodium yoelii Mei2-Like RNA Binding Protein Is Essential for Completion of Liver Stage Schizogony. Infect Immun 2016; 84:1336-1345. [PMID: 26883588 DOI: 10.1128/iai.01417-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 02/08/2016] [Indexed: 11/20/2022] Open
Abstract
Plasmodium parasites employ posttranscriptional regulatory mechanisms as their life cycle transitions between host cell invasion and replication within both the mosquito vector and mammalian host. RNA binding proteins (RBPs) provide one mechanism for modulation of RNA function. To explore the role of Plasmodium RBPs during parasite replication, we searched for RBPs that might play a role during liver stage development, the parasite stage that exhibits the most extensive growth and replication. We identified a parasite ortholog of the Mei2 (Meiosis inhibited 2) RBP that is conserved among Plasmodium species (PlasMei2) and exclusively transcribed in liver stage parasites. Epitope-tagged Plasmodium yoelii PlasMei2 was expressed only during liver stage schizogony and showed an apparent granular cytoplasmic location. Knockout of PlasMei2 (plasmei2(-)) in P. yoelii only affected late liver stage development. The P. yoelii plasmei2(-) liver stage size increased progressively until late in development, similar to wild-type parasite development. However, P. yoelii plasmei2(-) liver stage schizonts exhibited an abnormal DNA segregation phenotype and failed to form exoerythrocytic merozoites. Consequently the cellular integrity of P. yoelii plasmei2(-) liver stages became increasingly compromised late in development and the majority of P. yoelii plasmei2(-) underwent cell death by the time wild-type liver stages mature and release merozoites. This resulted in a complete block of P. yoelii plasmei2(-) transition from liver stage to blood stage infection in mice. Our results show for the first time the importance of a Plasmodium RBP in the coordinated progression of late liver stage schizogony and maturation of new invasive forms.
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76
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Zhang M, Kaneko I, Tsao T, Mitchell R, Nardin EH, Iwanaga S, Yuda M, Tsuji M. A highly infectious Plasmodium yoelii parasite, bearing Plasmodium falciparum circumsporozoite protein. Malar J 2016; 15:201. [PMID: 27068454 PMCID: PMC4828769 DOI: 10.1186/s12936-016-1248-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/30/2016] [Indexed: 12/31/2022] Open
Abstract
Background Plasmodium circumsporozoite protein (CSP) is a major surface antigen present in the sporozoite (Spz) stage of a malaria parasite. RTS, S vaccine, the most clinically advanced malaria vaccine, consists of a large portion of Plasmodium falciparum CSP (PfCSP). A highly infectious, recombinant rodent malaria, Plasmodium yoelii parasite bearing a full-length PfCSP, PfCSP/Py Spz, was needed as a tool to evaluate the role of PfCSP in mediating, protective, anti-malaria immunity in a mouse model. Methods A transgenic parasite, PfCSP/Py Spz, was generated by inserting a construct expressing the PfCSP at the locus of the P. yoelii CSP gene by double cross-over homologous recombination. Then the biological and protective properties of PfCSP/Py Spz were determined. Results This PfCSP/Py parasite produced up to 30,000 Spz in mosquito salivary glands, which is equal or even higher than the number of Spz produced by wild-type P. yoelii parasites. Five bites of PfCSP/Py-infected mosquitoes could induce blood infection in BALB/c mice. Conclusions The current study has demonstrated a successful establishment of a transgenic P. yoelii parasite clone that is able to express a full-length PfCSP, PfCSP/Py parasite. Importantly, this PfCSP/Py parasite can be as infectious as the wild-type P. yoelii parasite both in mosquito vector and in mouse, a mammalian host. A new transgenic parasite that expresses a full-length PfCSP may become a useful tool for researchers to investigate immunity against PfCSP in a mouse model.
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Affiliation(s)
- Min Zhang
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA.,Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Izumi Kaneko
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Tiffany Tsao
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA
| | - Robert Mitchell
- Division of Parasitology, Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Elizabeth H Nardin
- Division of Parasitology, Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Shiroh Iwanaga
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
| | - Masao Yuda
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan.
| | - Moriya Tsuji
- HIV and Malaria Vaccine Program, Aaron Diamond AIDS Research Center, Affiliate of The Rockefeller University, New York, NY, USA.
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Zheng W, Kou X, Du Y, Liu F, Yu C, Tsuboi T, Fan Q, Luo E, Cao Y, Cui L. Identification of three ookinete-specific genes and evaluation of their transmission-blocking potentials in Plasmodium berghei. Vaccine 2016; 34:2570-8. [PMID: 27083421 DOI: 10.1016/j.vaccine.2016.04.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/12/2016] [Accepted: 04/05/2016] [Indexed: 12/31/2022]
Abstract
With a renewed hope for malaria elimination, interventions that prevent transmission of parasites from humans to mosquitoes have received elevated attention. Transmission-blocking vaccines (TBVs) targeting the sexual stages are well suited for this task. Here, through bioinformatic analysis, we selected two putative Plasmodium berghei ookinete-stage proteins (PBANKA_111920, and PBANKA_145770) and a previously characterized ookinete protein PBANKA_135340 (PSOP7) for evaluation of their transmission-blocking potentials. Fragments of these predicted proteins were expressed in bacteria and purified recombinant proteins were used to immunize mice. Antisera against these recombinant proteins recognized proteins of predicted sizes from ookinete lysates and localized their expression on the surface of ookinetes. Inclusion of these antisera in in vitro ookinete culture significantly inhibited ookinete formation. Mosquitoes fed on mice immunized with the recombinant proteins also showed significantly reduced oocyst densities (60.0-70.7%) and modest reductions of oocyst prevalence (10.7-37.4%). These data, together with the conservation of these genes in Plasmodium, suggest that these three ookinete proteins could be new promising targets for TBVs and are worth of future investigations in the human malaria parasites.
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Affiliation(s)
- Wenqi Zheng
- Department of Pathogen Biology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China
| | - Xu Kou
- Department of Pathogen Biology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China; College of Animal Husbandry and Veterinary, Liaoning Medical University, Jinzhou, Liaoning 121001, China
| | - Yunting Du
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China
| | - Chunyun Yu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
| | - Qi Fan
- Dalian Institute of Biotechnology, Dalian, Liaoning, China
| | - Enjie Luo
- Department of Pathogen Biology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China.
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, China.
| | - Liwang Cui
- Department of Entomology, Pennsylvania State University, University Park, PA 16802, USA
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Plasmodium P-Type Cyclin CYC3 Modulates Endomitotic Growth during Oocyst Development in Mosquitoes. PLoS Pathog 2015; 11:e1005273. [PMID: 26565797 PMCID: PMC4643991 DOI: 10.1371/journal.ppat.1005273] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 10/21/2015] [Indexed: 11/20/2022] Open
Abstract
Cell-cycle progression and cell division in eukaryotes are governed in part by the cyclin family and their regulation of cyclin-dependent kinases (CDKs). Cyclins are very well characterised in model systems such as yeast and human cells, but surprisingly little is known about their number and role in Plasmodium, the unicellular protozoan parasite that causes malaria. Malaria parasite cell division and proliferation differs from that of many eukaryotes. During its life cycle it undergoes two types of mitosis: endomitosis in asexual stages and an extremely rapid mitotic process during male gametogenesis. Both schizogony (producing merozoites) in host liver and red blood cells, and sporogony (producing sporozoites) in the mosquito vector, are endomitotic with repeated nuclear replication, without chromosome condensation, before cell division. The role of specific cyclins during Plasmodium cell proliferation was unknown. We show here that the Plasmodium genome contains only three cyclin genes, representing an unusual repertoire of cyclin classes. Expression and reverse genetic analyses of the single Plant (P)-type cyclin, CYC3, in the rodent malaria parasite, Plasmodium berghei, revealed a cytoplasmic and nuclear location of the GFP-tagged protein throughout the lifecycle. Deletion of cyc3 resulted in defects in size, number and growth of oocysts, with abnormalities in budding and sporozoite formation. Furthermore, global transcript analysis of the cyc3-deleted and wild type parasites at gametocyte and ookinete stages identified differentially expressed genes required for signalling, invasion and oocyst development. Collectively these data suggest that cyc3 modulates oocyst endomitotic development in Plasmodium berghei. The malaria parasite is a single-celled organism that multiplies asexually in a non-canonical way in both vertebrate host and mosquito vector. In the mosquito midgut, atypical cell division occurs in oocysts, where repeated nuclear division (endomitosis) precedes cell division, which then gives rise to many sporozoites in a process known as sporogony. The molecular mechanisms controlling this process are poorly understood. In many model organisms including mouse and yeast cells the cell cycle is regulated by members of the cyclin protein family, but the role of this family in the malaria parasite is unknown. Here, we show that there are only three cyclin genes and investigate the function of the single P-type cyclin (CYC3) in the rodent malaria parasite, Plasmodium berghei. We show that CYC3 has a cytoplasmic and nuclear localisation throughout most of the parasite lifecycle and by gene deletion we demonstrate that CYC3 is important for normal oocyst development, maturation and sporozoite formation. Moreover, we show that deletion of cyc3 affects the transcription of genes required for cell signalling and oocyst development. The data suggest that CYC3 modulates asexual multiplication in oocysts and plays a vital role in parasite development in the mosquito.
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79
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Global transcriptional repression: An initial and essential step for Plasmodium sexual development. Proc Natl Acad Sci U S A 2015; 112:12824-9. [PMID: 26417110 DOI: 10.1073/pnas.1504389112] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Gametocytes are nonreplicative sexual forms that mediate malaria transmission to a mosquito vector. They are generated from asexual blood-stage parasites that proliferate in the circulation. However, little is known about how this transition is genetically regulated. Here, we report that an Apetala2 (AP2) family transcription factor, AP2-G2, regulates this transition as a transcriptional repressor. Disruption of AP2-G2 in the rodent malaria parasite Plasmodium berghei did not prevent commitment to the sexual stage but did halt development before the appearance of sex-specific morphologies. ChIP-seq analysis revealed that AP2-G2 targeted ∼1,500 genes and recognized a five-base motif in their promoters. Most of these target genes are required for asexual proliferation of the parasites in the blood, suggesting that AP2-G2 blocks the program that precedes asexual replication to promote conversion to the sexual stage. Microarray analysis showed that the identified targets constituted ∼70% of the up-regulated genes in AP2-G2-depleted parasites, suggesting that AP2-G2 actually functions as a repressor in gametocytes. A promoter assay using a centromere plasmid demonstrated that the binding motif functions as a cis-acting negative regulatory element. These results suggest that global transcriptional repression, which occurs during the initial phase of gametocytogenesis, is an essential step in Plasmodium sexual development.
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80
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Guttery DS, Poulin B, Ramaprasad A, Wall RJ, Ferguson DJP, Brady D, Patzewitz EM, Whipple S, Straschil U, Wright MH, Mohamed AMAH, Radhakrishnan A, Arold ST, Tate EW, Holder AA, Wickstead B, Pain A, Tewari R. Genome-wide functional analysis of Plasmodium protein phosphatases reveals key regulators of parasite development and differentiation. Cell Host Microbe 2015; 16:128-40. [PMID: 25011111 PMCID: PMC4094981 DOI: 10.1016/j.chom.2014.05.020] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/17/2014] [Accepted: 05/27/2014] [Indexed: 12/24/2022]
Abstract
Reversible protein phosphorylation regulated by kinases and phosphatases controls many cellular processes. Although essential functions for the malaria parasite kinome have been reported, the roles of most protein phosphatases (PPs) during Plasmodium development are unknown. We report a functional analysis of the Plasmodium berghei protein phosphatome, which exhibits high conservation with the P. falciparum phosphatome and comprises 30 predicted PPs with differential and distinct expression patterns during various stages of the life cycle. Gene disruption analysis of P. berghei PPs reveals that half of the genes are likely essential for asexual blood stage development, whereas six are required for sexual development/sporogony in mosquitoes. Phenotypic screening coupled with transcriptome sequencing unveiled morphological changes and altered gene expression in deletion mutants of two N-myristoylated PPs. These findings provide systematic functional analyses of PPs in Plasmodium, identify how phosphatases regulate parasite development and differentiation, and can inform the identification of drug targets for malaria. Phylogenetic analysis identifies 30 Plasmodium berghei protein phosphatases (PPs) Functional analysis reveals role for six PPs in sexual development/sporogony Two N-myristoylated PPs play key roles in sex allocation and parasite transmission RNA-Seq highlights significantly altered gene clusters in the N-myristoylated PP mutants
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Affiliation(s)
- David S Guttery
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Benoit Poulin
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Abhinay Ramaprasad
- Computational Bioscience Research Center (CBRC), Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Richard J Wall
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - David J P Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Declan Brady
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Eva-Maria Patzewitz
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Sarah Whipple
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Ursula Straschil
- Division of Cell and Molecular Biology, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Megan H Wright
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Alyaa M A H Mohamed
- Computational Bioscience Research Center (CBRC), Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Anand Radhakrishnan
- Computational Bioscience Research Center (CBRC), Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Stefan T Arold
- Computational Bioscience Research Center (CBRC), Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Edward W Tate
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Anthony A Holder
- Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
| | - Bill Wickstead
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK
| | - Arnab Pain
- Computational Bioscience Research Center (CBRC), Biological and Environmental Sciences and Engineering (BESE) Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia
| | - Rita Tewari
- Centre for Genetics and Genomics, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG2 7UH, UK.
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81
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Josling GA, Llinás M. Sexual development in Plasmodium parasites: knowing when it's time to commit. Nat Rev Microbiol 2015; 13:573-87. [DOI: 10.1038/nrmicro3519] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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82
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Ukegbu CV, Cho JS, Christophides GK, Vlachou D. Transcriptional silencing and activation of paternal DNA during Plasmodium berghei zygotic development and transformation to oocyst. Cell Microbiol 2015; 17:1230-40. [PMID: 25728487 PMCID: PMC4678591 DOI: 10.1111/cmi.12433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 02/24/2015] [Accepted: 02/24/2015] [Indexed: 11/29/2022]
Abstract
The malaria parasite develops sexually in the mosquito midgut upon entry with the ingested blood meal before it can invade the midgut epithelium and embark on sporogony. Recent data have identified a number of distinct transcriptional programmes operating during this critical phase of the parasite life cycle. We aimed at characterizing the parental contribution to these transcriptional programmes and establish the genetic framework that would guide further studies of Plasmodium zygotic development and ookinete-to-oocyst transition. To achieve this we used in vitro and in vivo cross-fertilization experiments of various parasite lines expressing fluorescent reporters under the control of constitutive and stage-specific promoters. The results revealed that the zygote/ookinete stage exhibits a maternal phenotype with respect to constitutively expressed reporters, which is derived from either maternal mRNA inheritance or transcription of the maternal allele. The respective paternal alleles are silenced in the zygote/ookinete but reactivated after midgut invasion and transformation to oocyst. Transcripts specifically produced in the zygote/ookinete are synthesized de novo by both parental alleles. These findings highlight a putative role of epigenetic regulation of Plasmodium zygotic development and add substantially to the emerging picture of the molecular mechanisms regulating this important stage of malaria transmission.
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Affiliation(s)
| | - Jee-Sun Cho
- Department of Life Sciences, Imperial College London, London, UK
| | - George K Christophides
- Department of Life Sciences, Imperial College London, London, UK
- The Cyprus Institute, Nicosia, Cyprus
| | - Dina Vlachou
- Department of Life Sciences, Imperial College London, London, UK
- The Cyprus Institute, Nicosia, Cyprus
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83
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Abstract
Malaria remains one of the leading causes of death worldwide, despite decades of public health efforts. The recent commitment by many endemic countries to eliminate malaria marks a shift away from programs aimed at controlling disease burden towards one that emphasizes reducing transmission of the most virulent human malaria parasite, Plasmodium falciparum. Gametocytes, the only developmental stage of malaria parasites able to infect mosquitoes, have remained understudied, as they occur in low numbers, do not cause disease, and are difficult to detect in vivo by conventional methods. Here, we review the transmission biology of P. falciparum gametocytes, featuring important recent discoveries of genes affecting parasite commitment to gametocyte formation, microvesicles enabling parasites to communicate with each other, and the anatomical site where immature gametocytes develop. We propose potential parasite targets for future intervention and highlight remaining knowledge gaps.
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Affiliation(s)
- Sandra K. Nilsson
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Lauren M. Childs
- Centre for Communicable Disease Dynamics and Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Caroline Buckee
- Centre for Communicable Disease Dynamics and Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
- * E-mail: (CB); (MM)
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
- * E-mail: (CB); (MM)
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84
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Kaneko I, Iwanaga S, Kato T, Kobayashi I, Yuda M. Genome-Wide Identification of the Target Genes of AP2-O, a Plasmodium AP2-Family Transcription Factor. PLoS Pathog 2015; 11:e1004905. [PMID: 26018192 PMCID: PMC4446032 DOI: 10.1371/journal.ppat.1004905] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 04/21/2015] [Indexed: 12/20/2022] Open
Abstract
Stage-specific transcription is a fundamental biological process in the life cycle of the Plasmodium parasite. Proteins containing the AP2 DNA-binding domain are responsible for stage-specific transcriptional regulation and belong to the only known family of transcription factors in Plasmodium parasites. Comprehensive identification of their target genes will advance our understanding of the molecular basis of stage-specific transcriptional regulation and stage-specific parasite development. AP2-O is an AP2 family transcription factor that is expressed in the mosquito midgut-invading stage, called the ookinete, and is essential for normal morphogenesis of this stage. In this study, we identified the genome-wide target genes of AP2-O by chromatin immunoprecipitation-sequencing and elucidate how this AP2 family transcription factor contributes to the formation of this motile stage. The analysis revealed that AP2-O binds specifically to the upstream genomic regions of more than 500 genes, suggesting that approximately 10% of the parasite genome is directly regulated by AP2-O. These genes are involved in distinct biological processes such as morphogenesis, locomotion, midgut penetration, protection against mosquito immunity and preparation for subsequent oocyst development. This direct and global regulation by AP2-O provides a model for gene regulation in Plasmodium parasites and may explain how these parasites manage to control their complex life cycle using a small number of sequence-specific AP2 transcription factors. Although malarial parasites have a complex life cycle, they harbor only 30 transcription factors in their genome. The majority of these transcription factors belong to a single family referred to as the AP2 family. Our previous study suggested that stage-specific AP2 family transcription factors have critical roles in maintaining the Plasmodium parasite life cycle. However, it remains fairly elusive as to how these transcription factors regulate each stage. AP2-O is an AP2 family transcription factor that is expressed during the mosquito midgut-invading stage, the ookinete, and is essential for normal development of this stage. In the present study, we identified the entire set of AP2-O target genes to elucidate how this AP2 family transcription factor contributes to the formation of this stage. Our results showed that AP2-O directly regulates 10% of the parasite genome and is involved in the whole process of mosquito midgut-invasion by ookinetes. The global and comprehensive regulation by the AP2 family transcription factor that we revealed provides a model for transcriptional regulation of this parasite and may explain how malarial parasites regulate their complex life cycle using a small number of sequence-specific transcription factors.
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Affiliation(s)
- Izumi Kaneko
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Shiroh Iwanaga
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Tomomi Kato
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Issei Kobayashi
- Core-Lab, Graduate School of Regional Innovation Studies, Mie University, Tsu, Mie, Japan
| | - Masao Yuda
- Department of Medical Zoology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
- * E-mail:
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85
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De Niz M, Helm S, Horstmann S, Annoura T, del Portillo HA, Khan SM, Heussler VT. In vivo and in vitro characterization of a Plasmodium liver stage-specific promoter. PLoS One 2015; 10:e0123473. [PMID: 25874388 PMCID: PMC4398466 DOI: 10.1371/journal.pone.0123473] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 03/03/2015] [Indexed: 12/28/2022] Open
Abstract
Little is known about stage-specific gene regulation in Plasmodium parasites, in particular the liver stage of development. We have previously described in the Plasmodium berghei rodent model, a liver stage-specific (lisp2) gene promoter region, in vitro. Using a dual luminescence system, we now confirm the stage specificity of this promoter region also in vivo. Furthermore, by substitution and deletion analyses we have extended our in vitro characterization of important elements within the promoter region. Importantly, the dual luminescence system allows analyzing promoter constructs avoiding mouse-consuming cloning procedures of transgenic parasites. This makes extensive mutation and deletion studies a reasonable approach also in the malaria mouse model. Stage-specific expression constructs and parasite lines are extremely valuable tools for research on Plasmodium liver stage biology. Such reporter lines offer a promising opportunity for assessment of liver stage drugs, characterization of genetically attenuated parasites and liver stage-specific vaccines both in vivo and in vitro, and may be key for the generation of inducible systems.
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Affiliation(s)
- Mariana De Niz
- Institute of Cell Biology, University of Bern, Bern, Switzerland
- * E-mail:
| | - Susanne Helm
- Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Sebastian Horstmann
- Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Takeshi Annoura
- Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
- Department of Parasitology, National Institute of Infectious Diseases (NIID), Tokyo, Japan
| | - Hernando A. del Portillo
- Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Shahid M. Khan
- Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
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Brancucci NMB, Bertschi NL, Zhu L, Niederwieser I, Chin WH, Wampfler R, Freymond C, Rottmann M, Felger I, Bozdech Z, Voss TS. Heterochromatin protein 1 secures survival and transmission of malaria parasites. Cell Host Microbe 2015; 16:165-176. [PMID: 25121746 DOI: 10.1016/j.chom.2014.07.004] [Citation(s) in RCA: 187] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 04/28/2014] [Accepted: 06/06/2014] [Indexed: 12/14/2022]
Abstract
Clonally variant expression of surface antigens allows the malaria parasite Plasmodium falciparum to evade immune recognition during blood stage infection and secure malaria transmission. We demonstrate that heterochromatin protein 1 (HP1), an evolutionary conserved regulator of heritable gene silencing, controls expression of numerous P. falciparum virulence genes as well as differentiation into the sexual forms that transmit to mosquitoes. Conditional depletion of P. falciparum HP1 (PfHP1) prevents mitotic proliferation of blood stage parasites and disrupts mutually exclusive expression and antigenic variation of the major virulence factor PfEMP1. Additionally, PfHP1-dependent regulation of PfAP2-G, a transcription factor required for gametocyte conversion, controls the switch from asexual proliferation to sexual differentiation, providing insight into the epigenetic mechanisms underlying gametocyte commitment. These findings show that PfHP1 is centrally involved in clonally variant gene expression and sexual differentiation in P. falciparum and have major implications for developing antidisease and transmission-blocking interventions against malaria.
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Affiliation(s)
- Nicolas M B Brancucci
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Nicole L Bertschi
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Lei Zhu
- School of Biological Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Igor Niederwieser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Wai Hoe Chin
- School of Biological Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Rahel Wampfler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Céline Freymond
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Matthias Rottmann
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Ingrid Felger
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Till S Voss
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland; University of Basel, Petersplatz 1, Basel 4003, Switzerland.
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87
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Pinheiro MM, Ahmed MA, Millar SB, Sanderson T, Otto TD, Lu WC, Krishna S, Rayner JC, Cox-Singh J. Plasmodium knowlesi genome sequences from clinical isolates reveal extensive genomic dimorphism. PLoS One 2015; 10:e0121303. [PMID: 25830531 PMCID: PMC4382175 DOI: 10.1371/journal.pone.0121303] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 01/30/2015] [Indexed: 11/21/2022] Open
Abstract
Plasmodium knowlesi is a newly described zoonosis that causes malaria in the human population that can be severe and fatal. The study of P. knowlesi parasites from human clinical isolates is relatively new and, in order to obtain maximum information from patient sample collections, we explored the possibility of generating P. knowlesi genome sequences from archived clinical isolates. Our patient sample collection consisted of frozen whole blood samples that contained excessive human DNA contamination and, in that form, were not suitable for parasite genome sequencing. We developed a method to reduce the amount of human DNA in the thawed blood samples in preparation for high throughput parasite genome sequencing using Illumina HiSeq and MiSeq sequencing platforms. Seven of fifteen samples processed had sufficiently pure P. knowlesi DNA for whole genome sequencing. The reads were mapped to the P. knowlesi H strain reference genome and an average mapping of 90% was obtained. Genes with low coverage were removed leaving 4623 genes for subsequent analyses. Previously we identified a DNA sequence dimorphism on a small fragment of the P. knowlesi normocyte binding protein xa gene on chromosome 14. We used the genome data to assemble full-length Pknbpxa sequences and discovered that the dimorphism extended along the gene. An in-house algorithm was developed to detect SNP sites co-associating with the dimorphism. More than half of the P. knowlesi genome was dimorphic, involving genes on all chromosomes and suggesting that two distinct types of P. knowlesi infect the human population in Sarawak, Malaysian Borneo. We use P. knowlesi clinical samples to demonstrate that Plasmodium DNA from archived patient samples can produce high quality genome data. We show that analyses, of even small numbers of difficult clinical malaria isolates, can generate comprehensive genomic information that will improve our understanding of malaria parasite diversity and pathobiology.
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Affiliation(s)
- Miguel M. Pinheiro
- School of Medicine, University of St Andrews, Medical and Biological Sciences Building, North Haugh, St Andrews, United Kingdom
| | - Md Atique Ahmed
- Malaria Research Centre, University Malaysia Sarawak, Kuching, Sarawak, Malaysia
| | - Scott B. Millar
- School of Medicine, University of St Andrews, Medical and Biological Sciences Building, North Haugh, St Andrews, United Kingdom
| | - Theo Sanderson
- Malaria Programme, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Thomas D. Otto
- Malaria Programme, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Woon Chan Lu
- Sarikei Hospital, Sarikei, Sarawak, 96100, Malaysia
| | - Sanjeev Krishna
- Division of Clinical Sciences, St. George’s, University of London, London, United Kingdom
| | - Julian C. Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Janet Cox-Singh
- School of Medicine, University of St Andrews, Medical and Biological Sciences Building, North Haugh, St Andrews, United Kingdom
- * E-mail:
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88
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Russell K, Emes R, Horrocks P. Triaging informative cis-regulatory elements for the combinatorial control of temporal gene expression during Plasmodium falciparum intraerythrocytic development. Parasit Vectors 2015; 8:81. [PMID: 25652008 PMCID: PMC4322800 DOI: 10.1186/s13071-015-0701-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 01/27/2015] [Indexed: 01/18/2023] Open
Abstract
Background Over 2700 genes are subject to stage-specific regulation during the intraerythrocytic development of the human malaria parasite Plasmodium falciparum. Bioinformatic analyses have identified a large number of over-represented motifs in the 5′ flanking regions of these genes that may act as cis-acting factors in the promoter-based control of temporal expression. Triaging these lists to provide candidates most likely to play a role in regulating temporal expression is challenging, but important if we are to effectively design in vitro studies to validate this role. Methods We report here the application of a repeated search of variations of 5′ flanking sequences from P. falciparum using the Finding Informative Regulatory Elements (FIRE) algorithm. Results Our approach repeatedly found a short-list of high scoring DNA motifs, for which cognate specific transcription factors were available, that appear to be typically associated with upregulation of mRNA accumulation during the first half of intraerythrocytic development. Conclusions We propose these cis-trans interactions may provide a combinatorial promoter-based control of gene expression to complement more global mechanisms of gene regulation that can account for temporal control during the second half of intraerythrocytic development. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-0701-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Karen Russell
- Institute for Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK.
| | - Richard Emes
- School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, LE12 5RD, UK. .,Advanced Data Analysis Centre, University of Nottingham, Leicestershire, LE12 5RD, UK.
| | - Paul Horrocks
- Institute for Science and Technology in Medicine, Keele University, Staffordshire, ST5 5BG, UK.
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89
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Sinden RE. The cell biology of malaria infection of mosquito: advances and opportunities. Cell Microbiol 2015; 17:451-66. [PMID: 25557077 PMCID: PMC4409862 DOI: 10.1111/cmi.12413] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/12/2014] [Accepted: 12/24/2014] [Indexed: 01/01/2023]
Abstract
Recent reviews (Feachem et al.; Alonso et al.) have concluded that in order to have a sustainable impact on the global burden of malaria, it is essential that we knowingly reduce the global incidence of infected persons. To achieve this we must reduce the basic reproductive rate of the parasites to < 1 in diverse epidemiological settings. This can be achieved by impacting combinations of the following parameters: the number of mosquitoes relative to the number of persons, the mosquito/human biting rate, the proportion of mosquitoes carrying infectious sporozoites, the daily survival rate of the infectious mosquito and the ability of malaria-infected persons to infect mosquito vectors. This paper focuses on our understanding of parasite biology underpinning the last of these terms: infection of the mosquito. The article attempts to highlight central issues that require further study to assist in the discovery of useful transmission-blocking measures.
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Affiliation(s)
- R E Sinden
- Department of Life Sciences, Imperial College London and the Jenner Institute, The University of Oxford, Oxford, UK
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90
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Akinosoglou KA, Bushell ESC, Ukegbu CV, Schlegelmilch T, Cho JS, Redmond S, Sala K, Christophides GK, Vlachou D. Characterization of Plasmodium developmental transcriptomes in Anopheles gambiae midgut reveals novel regulators of malaria transmission. Cell Microbiol 2015; 17:254-68. [PMID: 25225164 PMCID: PMC4371638 DOI: 10.1111/cmi.12363] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 08/27/2014] [Accepted: 09/08/2014] [Indexed: 12/24/2022]
Abstract
The passage through the mosquito is a major bottleneck for malaria parasite populations and a target of interventions aiming to block disease transmission. Here, we used DNA microarrays to profile the developmental transcriptomes of the rodent malaria parasite Plasmodium berghei in vivo, in the midgut of Anopheles gambiae mosquitoes, from parasite stages in the midgut blood bolus to sporulating oocysts on the basal gut wall. Data analysis identified several distinct transcriptional programmes encompassing genes putatively involved in developmental processes or in interactions with the mosquito. At least two of these programmes are associated with the ookinete development that is linked to mosquito midgut invasion and establishment of infection. Targeted disruption by homologous recombination of two of these genes resulted in mutant parasites exhibiting notable infection phenotypes. GAMER encodes a short polypeptide with granular localization in the gametocyte cytoplasm and shows a highly penetrant loss-of-function phenotype manifested as greatly reduced ookinete numbers, linked to impaired male gamete release. HADO encodes a putative magnesium phosphatase with distinctive cortical localization along the concave ookinete periphery. Disruption of HADO compromises ookinete development leading to significant reduction of oocyst numbers. Our data provide important insights into the molecular framework underpinning Plasmodium development in the mosquito and identifies two genes with important functions at initial stages of parasite development in the mosquito midgut.
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Affiliation(s)
| | | | | | | | - Jee-Sun Cho
- Department of Life Sciences, Imperial College LondonLondon, UK
| | - Seth Redmond
- Department of Life Sciences, Imperial College LondonLondon, UK
| | - Katarzyna Sala
- Department of Life Sciences, Imperial College LondonLondon, UK
| | - George K Christophides
- Department of Life Sciences, Imperial College LondonLondon, UK
- The Cyprus InstituteNicosia, Cyprus
| | - Dina Vlachou
- Department of Life Sciences, Imperial College LondonLondon, UK
- The Cyprus InstituteNicosia, Cyprus
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91
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Croken MM, Ma Y, Markillie LM, Taylor RC, Orr G, Weiss LM, Kim K. Distinct Strains of Toxoplasma gondii Feature Divergent Transcriptomes Regardless of Developmental Stage. PLoS One 2014; 9:e111297. [PMID: 25393307 PMCID: PMC4230917 DOI: 10.1371/journal.pone.0111297] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/19/2014] [Indexed: 11/18/2022] Open
Affiliation(s)
- Matthew McKnight Croken
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Yanfen Ma
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Lye Meng Markillie
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Ronald C. Taylor
- Computational Biology and Bioinformatics Group, Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Galya Orr
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington, United States of America
| | - Louis M. Weiss
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, United States of America
- * E-mail: (LMW); (KK)
| | - Kami Kim
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, United States of America
- * E-mail: (LMW); (KK)
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92
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Guerreiro A, Deligianni E, Santos JM, Silva PAGC, Louis C, Pain A, Janse CJ, Franke-Fayard B, Carret CK, Siden-Kiamos I, Mair GR. Genome-wide RIP-Chip analysis of translational repressor-bound mRNAs in the Plasmodium gametocyte. Genome Biol 2014; 15:493. [PMID: 25418785 PMCID: PMC4234863 DOI: 10.1186/s13059-014-0493-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 10/09/2014] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Following fertilization, the early proteomes of metazoans are defined by the translation of stored but repressed transcripts; further embryonic development relies on de novo transcription of the zygotic genome. During sexual development of Plasmodium berghei, a rodent model for human malaria species including P. falciparum, the stability of repressed mRNAs requires the translational repressors DOZI and CITH. When these repressors are absent, Plasmodium zygote development and transmission to the mosquito vector is halted, as hundreds of transcripts become destabilized. However, which mRNAs are direct targets of these RNA binding proteins, and thus subject to translational repression, is unknown. RESULTS We identify the maternal mRNA contribution to post-fertilization development of P. berghei using RNA immunoprecipitation and microarray analysis. We find that 731 mRNAs, approximately 50% of the transcriptome, are associated with DOZI and CITH, allowing zygote development to proceed in the absence of RNA polymerase II transcription. Using GFP-tagging, we validate the repression phenotype of selected genes and identify mRNAs relying on the 5' untranslated region for translational control. Gene deletion reveals a novel protein located in the ookinete crystalloid with an essential function for sporozoite development. CONCLUSIONS Our study details for the first time the P. berghei maternal repressome. This mRNA population provides the developing ookinete with coding potential for key molecules required for life-cycle progression, and that are likely to be critical for the transmission of the malaria parasite from the rodent and the human host to the mosquito vector.
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Affiliation(s)
- Ana Guerreiro
- />Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Elena Deligianni
- />Institute of Molecular Biology and Biotechnology (IMBB), Foundation of Research and Technology (FORTH), N. Plastira 100, Heraklio, Crete P.C. 71110 Greece
| | - Jorge M Santos
- />Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Patricia AGC Silva
- />Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Christos Louis
- />Institute of Molecular Biology and Biotechnology (IMBB), Foundation of Research and Technology (FORTH), N. Plastira 100, Heraklio, Crete P.C. 71110 Greece
| | - Arnab Pain
- />Pathogen Genomics Laboratory, Computational Bioscience Research Center, King Abdullah University of Science and Technology, Thuwal-Jeddah, Saudi Arabia
| | - Chris J Janse
- />Department of Parasitology, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Celine K Carret
- />Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Inga Siden-Kiamos
- />Institute of Molecular Biology and Biotechnology (IMBB), Foundation of Research and Technology (FORTH), N. Plastira 100, Heraklio, Crete P.C. 71110 Greece
| | - Gunnar R Mair
- />Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
- />Parasitology, Department of Infectious Diseases, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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93
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Mouveaux T, Oria G, Werkmeister E, Slomianny C, Fox BA, Bzik DJ, Tomavo S. Nuclear glycolytic enzyme enolase of Toxoplasma gondii functions as a transcriptional regulator. PLoS One 2014; 9:e105820. [PMID: 25153525 PMCID: PMC4143315 DOI: 10.1371/journal.pone.0105820] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 07/28/2014] [Indexed: 01/07/2023] Open
Abstract
Apicomplexan parasites including Toxoplasma gondii have complex life cycles within different hosts and their infectivity relies on their capacity to regulate gene expression. However, little is known about the nuclear factors that regulate gene expression in these pathogens. Here, we report that T. gondii enolase TgENO2 is targeted to the nucleus of actively replicating parasites, where it specifically binds to nuclear chromatin in vivo. Using a ChIP-Seq technique, we provide evidence for TgENO2 enrichment at the 5′ untranslated gene regions containing the putative promoters of 241 nuclear genes. Ectopic expression of HA-tagged TgENO1 or TgENO2 led to changes in transcript levels of numerous gene targets. Targeted disruption of TgENO1 gene results in a decrease in brain cyst burden of chronically infected mice and in changes in transcript levels of several nuclear genes. Complementation of this knockout mutant with ectopic TgENO1-HA fully restored normal transcript levels. Our findings reveal that enolase functions extend beyond glycolytic activity and include a direct role in coordinating gene regulation in T. gondii.
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Affiliation(s)
- Thomas Mouveaux
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U 1019, Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
| | - Gabrielle Oria
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U 1019, Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
| | - Elisabeth Werkmeister
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U 1019, Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
| | - Christian Slomianny
- Laboratory of Cell Physiology, INSERM U 1003, Université Lille Nord de France, Villeneuve d'Ascq, France
| | - Barbara A. Fox
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, United States of America
| | - David J. Bzik
- Department of Microbiology and Immunology, The Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, United States of America
| | - Stanislas Tomavo
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U 1019, Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
- * E-mail:
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94
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Yamagishi J, Wakaguri H, Yokoyama N, Yamashita R, Suzuki Y, Xuan X, Igarashi I. The Babesia bovis gene and promoter model: an update from full-length EST analysis. BMC Genomics 2014; 15:678. [PMID: 25124460 PMCID: PMC4148916 DOI: 10.1186/1471-2164-15-678] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 07/08/2014] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Babesia bovis is an apicomplexan parasite that causes babesiosis in infected cattle. Genomes of pathogens contain promising information that can facilitate the development of methods for controlling infections. Although the genome of B. bovis is publically available, annotated gene models are not highly reliable prior to experimental validation. Therefore, we validated a preproposed gene model of B. bovis and extended the associated annotations on the basis of experimentally obtained full-length expressed sequence tags (ESTs). RESULTS From in vitro cultured merozoites, 12,286 clones harboring full-length cDNAs were sequenced from both ends using the Sanger method, and 6,787 full-length cDNAs were assembled. These were then clustered, and a nonredundant referential data set of 2,115 full-length cDNA sequences was constructed. The comparison of the preproposed gene model with our data set identified 310 identical genes, 342 almost identical genes, 1,054 genes with potential structural inconsistencies, and 409 novel genes. The median length of 5' untranslated regions (UTRs) was 152 nt. Subsequently, we identified 4,086 transcription start sites (TSSs) and 2,023 transcriptionally active regions (TARs) by examining 5' ESTs. We identified ATGGGG and CCCCAT sites as consensus motifs in TARs that were distributed around -50 bp from TSSs. In addition, we found ACACA, TGTGT, and TATAT sites, which were distributed periodically around TSSs in cycles of approximately 150 bp. Moreover, related periodical distributions were not observed in mammalian promoter regions. CONCLUSIONS The observations in this study indicate the utility of integrated bioinformatics and experimental data for improving genome annotations. In particular, full-length cDNAs with one-base resolution for TSSs enabled the identification of consensus motifs in promoter sequences and demonstrated clear distributions of identified motifs. These observations allowed the illustration of a model promoter composition, which supports the differences in transcriptional regulation frameworks between apicomplexan parasites and mammals.
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Affiliation(s)
- Junya Yamagishi
- />Tohoku Medical Megabank Organization, Tohoku University, 6-3-09, aza Aoba, Sendai, Miyagi 980-8579 Japan
- />National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho west 2-13, Obihiro, Hokkaido 080-8555 Japan
| | - Hiroyuki Wakaguri
- />Department of Medical Genome Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562 Japan
| | - Naoaki Yokoyama
- />National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho west 2-13, Obihiro, Hokkaido 080-8555 Japan
| | - Riu Yamashita
- />Tohoku Medical Megabank Organization, Tohoku University, 6-3-09, aza Aoba, Sendai, Miyagi 980-8579 Japan
| | - Yutaka Suzuki
- />Department of Medical Genome Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562 Japan
| | - Xuenan Xuan
- />National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho west 2-13, Obihiro, Hokkaido 080-8555 Japan
| | - Ikuo Igarashi
- />National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho west 2-13, Obihiro, Hokkaido 080-8555 Japan
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95
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Oberstaller J, Pumpalova Y, Schieler A, Llinás M, Kissinger JC. The Cryptosporidium parvum ApiAP2 gene family: insights into the evolution of apicomplexan AP2 regulatory systems. Nucleic Acids Res 2014; 42:8271-84. [PMID: 24957599 PMCID: PMC4117751 DOI: 10.1093/nar/gku500] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 05/15/2014] [Accepted: 05/19/2014] [Indexed: 01/13/2023] Open
Abstract
We provide the first comprehensive analysis of any transcription factor family in Cryptosporidium, a basal-branching apicomplexan that is the second leading cause of infant diarrhea globally. AP2 domain-containing proteins have evolved to be the major regulatory family in the phylum to the exclusion of canonical regulators. We show that apicomplexan and perkinsid AP2 domains cluster distinctly from other chromalveolate AP2s. Protein-binding specificity assays of C. parvum AP2 domains combined with motif conservation upstream of co-regulated gene clusters allowed the construction of putative AP2 regulons across the in vitro life cycle. Orthologous Apicomplexan AP2 (ApiAP2) expression has been rearranged relative to the malaria parasite P. falciparum, suggesting ApiAP2 network rewiring during evolution. C. hominis orthologs of putative C. parvum ApiAP2 proteins and target genes show greater than average variation. C. parvum AP2 domains display reduced binding diversity relative to P. falciparum, with multiple domains binding the 5'-TGCAT-3', 5'-CACACA-3' and G-box motifs (5'-G[T/C]GGGG-3'). Many overrepresented motifs in C. parvum upstream regions are not AP2 binding motifs. We propose that C. parvum is less reliant on ApiAP2 regulators in part because it utilizes E2F/DP1 transcription factors. C. parvum may provide clues to the ancestral state of apicomplexan transcriptional regulation, pre-AP2 domination.
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Affiliation(s)
- Jenna Oberstaller
- Department of Genetics, University of Georgia, Athens, GA 30602, USA Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Yoanna Pumpalova
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Ariel Schieler
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Manuel Llinás
- Department of Molecular Biology and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Jessica C Kissinger
- Department of Genetics, University of Georgia, Athens, GA 30602, USA Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
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96
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Kafsack BFC, Rovira-Graells N, Clark TG, Bancells C, Crowley VM, Campino SG, Williams AE, Drought LG, Kwiatkowski DP, Baker DA, Cortés A, Llinás M. A transcriptional switch underlies commitment to sexual development in malaria parasites. Nature 2014; 507:248-52. [PMID: 24572369 PMCID: PMC4040541 DOI: 10.1038/nature12920] [Citation(s) in RCA: 349] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 11/27/2013] [Indexed: 02/07/2023]
Abstract
The life cycles of many parasites involve transitions between disparate host species, requiring these parasites to go through multiple developmental stages adapted to each of these specialized niches. Transmission of malaria parasites (Plasmodium spp.) from humans to the mosquito vector requires differentiation from asexual stages replicating within red blood cells into non-dividing male and female gametocytes. Although gametocytes were first described in 1880, our understanding of the molecular mechanisms involved in commitment to gametocyte formation is extremely limited, and disrupting this critical developmental transition remains a long-standing goal. Here we show that expression levels of the DNA-binding protein PfAP2-G correlate strongly with levels of gametocyte formation. Using independent forward and reverse genetics approaches, we demonstrate that PfAP2-G function is essential for parasite sexual differentiation. By combining genome-wide PfAP2-G cognate motif occurrence with global transcriptional changes resulting from PfAP2-G ablation, we identify early gametocyte genes as probable targets of PfAP2-G and show that their regulation by PfAP2-G is critical for their wild-type level expression. In the asexual blood-stage parasites pfap2-g appears to be among a set of epigenetically silenced loci prone to spontaneous activation. Stochastic activation presents a simple mechanism for a low baseline of gametocyte production. Overall, these findings identify PfAP2-G as a master regulator of sexual-stage development in malaria parasites and mark the first discovery of a transcriptional switch controlling a differentiation decision in protozoan parasites.
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Affiliation(s)
- Björn F C Kafsack
- 1] Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA [2] Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA (B.F.C.K.); Department of Molecular Biology and Center for Infectious Disease Dynamics, The Pennsylvania State University, State College, Pennsylvania 16802, USA (V.M.C., M.L.)
| | - Núria Rovira-Graells
- 1] Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, 08036 Catalonia, Spain [2] Institute for Research in Biomedicine (IRB), Barcelona, 08028 Catalonia, Spain
| | - Taane G Clark
- 1] Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK [2] Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Cristina Bancells
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, 08036 Catalonia, Spain
| | - Valerie M Crowley
- 1] Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA [2] Institute for Research in Biomedicine (IRB), Barcelona, 08028 Catalonia, Spain [3] Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA (B.F.C.K.); Department of Molecular Biology and Center for Infectious Disease Dynamics, The Pennsylvania State University, State College, Pennsylvania 16802, USA (V.M.C., M.L.)
| | - Susana G Campino
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - April E Williams
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA
| | - Laura G Drought
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Dominic P Kwiatkowski
- 1] Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK [2] Wellcome Trust Sanger Centre for Human Genetics, Oxford OX3 7BN, UK
| | - David A Baker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Alfred Cortés
- 1] Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, 08036 Catalonia, Spain [2] Institute for Research in Biomedicine (IRB), Barcelona, 08028 Catalonia, Spain [3] Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, 08010 Catalonia, Spain
| | - Manuel Llinás
- 1] Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA [2] Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA [3] Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA (B.F.C.K.); Department of Molecular Biology and Center for Infectious Disease Dynamics, The Pennsylvania State University, State College, Pennsylvania 16802, USA (V.M.C., M.L.)
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97
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Sinha A, Hughes KR, Modrzynska KK, Otto TD, Pfander C, Dickens NJ, Religa AA, Bushell E, Graham AL, Cameron R, Kafsack BF, Williams AE, Llinas M, Berriman M, Billker O, Waters AP. A cascade of DNA-binding proteins for sexual commitment and development in Plasmodium. Nature 2014; 507:253-257. [PMID: 24572359 PMCID: PMC4105895 DOI: 10.1038/nature12970] [Citation(s) in RCA: 299] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 12/19/2013] [Indexed: 12/04/2022]
Abstract
Commitment to and completion of sexual development are essential for malaria parasites (protists of the genus Plasmodium) to be transmitted through mosquitoes. The molecular mechanism(s) responsible for commitment have been hitherto unknown. Here we show that PbAP2-G, a conserved member of the apicomplexan AP2 (ApiAP2) family of DNA-binding proteins, is essential for the commitment of asexually replicating forms to sexual development in Plasmodium berghei, a malaria parasite of rodents. PbAP2-G was identified from mutations in its encoding gene, PBANKA_143750, which account for the loss of sexual development frequently observed in parasites transmitted artificially by blood passage. Systematic gene deletion of conserved ApiAP2 genes in Plasmodium confirmed the role of PbAP2-G and revealed a second ApiAP2 member (PBANKA_103430, here termed PbAP2-G2) that significantly modulates but does not abolish gametocytogenesis, indicating that a cascade of ApiAP2 proteins are involved in commitment to the production and maturation of gametocytes. The data suggest a mechanism of commitment to gametocytogenesis in Plasmodium consistent with a positive feedback loop involving PbAP2-G that could be exploited to prevent the transmission of this pernicious parasite.
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Affiliation(s)
- Abhinav Sinha
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow
| | - Katie R. Hughes
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow
| | | | | | | | | | | | - Ellen Bushell
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK
| | - Anne L. Graham
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow
| | - Rachael Cameron
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow
| | - Bjorn F.C. Kafsack
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA
| | - April E. Williams
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA
| | - Manuel Llinas
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA
| | | | | | - Andrew P. Waters
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow
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98
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Wang J, Dixon SE, Ting LM, Liu TK, Jeffers V, Croken MM, Calloway M, Cannella D, Ali Hakimi M, Kim K, Sullivan WJ. Lysine acetyltransferase GCN5b interacts with AP2 factors and is required for Toxoplasma gondii proliferation. PLoS Pathog 2014; 10:e1003830. [PMID: 24391497 PMCID: PMC3879359 DOI: 10.1371/journal.ppat.1003830] [Citation(s) in RCA: 50] [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: 05/14/2013] [Accepted: 10/26/2013] [Indexed: 12/26/2022] Open
Abstract
Histone acetylation has been linked to developmental changes in gene expression and is a validated drug target of apicomplexan parasites, but little is known about the roles of individual histone modifying enzymes and how they are recruited to target genes. The protozoan parasite Toxoplasma gondii (phylum Apicomplexa) is unusual among invertebrates in possessing two GCN5-family lysine acetyltransferases (KATs). While GCN5a is required for gene expression in response to alkaline stress, this KAT is dispensable for parasite proliferation in normal culture conditions. In contrast, GCN5b cannot be disrupted, suggesting it is essential for Toxoplasma viability. To further explore the function of GCN5b, we generated clonal parasites expressing an inducible HA-tagged dominant-negative form of GCN5b containing a point mutation that ablates enzymatic activity (E703G). Stabilization of this dominant-negative GCN5b was mediated through ligand-binding to a destabilization domain (dd) fused to the protein. Induced accumulation of the ddHAGCN5b(E703G) protein led to a rapid arrest in parasite replication. Growth arrest was accompanied by a decrease in histone H3 acetylation at specific lysine residues as well as reduced expression of GCN5b target genes in GCN5b(E703G) parasites, which were identified using chromatin immunoprecipitation coupled with microarray hybridization (ChIP-chip). Proteomics studies revealed that GCN5b interacts with AP2-domain proteins, apicomplexan plant-like transcription factors, as well as a “core complex” that includes the co-activator ADA2-A, TFIID subunits, LEO1 polymerase-associated factor (Paf1) subunit, and RRM proteins. The dominant-negative phenotype of ddHAGCN5b(E703G) parasites, considered with the proteomics and ChIP-chip data, indicate that GCN5b plays a central role in transcriptional and chromatin remodeling complexes. We conclude that GCN5b has a non-redundant and indispensable role in regulating gene expression required during the Toxoplasma lytic cycle. Toxoplasma gondii is a protozoan parasite that causes significant opportunistic infection in AIDS and other immunocompromised patients. Acute episodes of toxoplasmosis stem from tissue destruction caused by the rapidly growing form of the parasite, the tachyzoite. In this study, we identify a lysine acetyltransferase (KAT) enzyme called GCN5b that is an essential driver of tachyzoite proliferation. Our studies show that GCN5b is present at a wide variety of parasite genes and that expression of defective GCN5b compromises gene expression through its diminished ability to acetylate histone proteins. We also identified the likely mechanism by which GCN5b is recruited to target genes by co-purifying this KAT with plant-like AP2-domain proteins, a subset of which function as DNA-binding transcription factors in Apicomplexa. Our findings demonstrate that KATs play a critical role in parasite replication, which leads to tissue destruction and acute disease in the host. Parasite KAT enzyme complexes may therefore serve as attractive targets for future drug development.
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Affiliation(s)
- Jiachen Wang
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Stacy E. Dixon
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Li-Min Ting
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Ting-Kai Liu
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Victoria Jeffers
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Matthew M. Croken
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - Myrasol Calloway
- Laboratory for Macromolecular Analysis, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | | | | | - Kami Kim
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, Bronx, New York, New York, United States of America
| | - William J. Sullivan
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Microbiology & Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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99
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Kramer S. RNA in development: how ribonucleoprotein granules regulate the life cycles of pathogenic protozoa. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 5:263-84. [PMID: 24339376 DOI: 10.1002/wrna.1207] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 10/22/2013] [Accepted: 10/29/2013] [Indexed: 12/11/2022]
Abstract
Ribonucleoprotein (RNP) granules are important posttranscriptional regulators of messenger RNA (mRNA) fate. Several types of RNP granules specifically regulate gene expression during development of multicellular organisms and are commonly referred to as germ granules. The function of germ granules is not entirely understood and probably diverse, but it is generally agreed that one main function is posttranscriptional regulation of gene expression during early development, when transcription is silent. One example is the translational repression of maternally derived mRNAs in oocytes. Here, I hope to show that the need for regulation of gene expression by RNP granules is not restricted to animal development, but plays an equally important role during the development of pathogenic protozoa. Apicomplexa and Trypanosomatidae have complex life cycles with frequent host changes. The need to quickly adapt gene expression to a new environment as well as the ability to suppress translation to survive latencies is critical for successful completion of life cycles. Posttranscriptional gene regulation is not necessarily simpler in protozoa. Apicomplexa surprise with the presence of micro RNA (miRNAs) and upstream open reading frames (µORFs). Trypanosomes have an unusually large repertoire of different RNP granule types. A better understanding of RNP granules in protozoa may help to gain insight into the evolutionary origin of RNP granules: Trypanosomes for example have two types of granules with interesting similarities to animal germ granules.
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Affiliation(s)
- Susanne Kramer
- Lehrstuhl für Zell- und Entwicklungsbiologie, Biozentrum, Universität Würzburg, Würzburg, Germany
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100
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Duffy MF, Selvarajah SA, Josling GA, Petter M. Epigenetic regulation of the Plasmodium falciparum genome. Brief Funct Genomics 2013; 13:203-16. [PMID: 24326119 DOI: 10.1093/bfgp/elt047] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recent research has highlighted some unique aspects of chromatin biology in the malaria parasite Plasmodium falciparum. During its erythrocytic lifecycle P. falciparum maintains its genome primarily as unstructured euchromatin. Indeed there is no clear role for chromatin-mediated silencing of the majority of the developmentally expressed genes in P. falciparum. However discontinuous stretches of heterochromatin are critical for variegated expression of contingency genes that mediate key pathogenic processes in malaria. These range from invasion of erythrocytes and antigenic variation to solute transport and growth adaptation in response to environmental changes. Despite lack of structure within euchromatin the nucleus maintains functional compartments that regulate expression of many genes at the nuclear periphery, particularly genes with clonally variant expression. The typical components of the chromatin regulatory machinery are present in P. falciparum; however, some of these appear to have evolved novel species-specific functions, e.g. the dynamic regulation of histone variants at virulence gene promoters. The parasite also appears to have repeatedly acquired chromatin regulatory proteins through lateral transfer from endosymbionts and from the host. P. falciparum chromatin regulators have been successfully targeted with multiple drugs in laboratory studies; hopefully their functional divergence from human counterparts will allow the development of parasite-specific inhibitors.
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