1
|
Lee BST, Sinha A, Dedon P, Preiser P. Charting new territory: The Plasmodium falciparum tRNA modification landscape. Biomed J 2024:100745. [PMID: 38734409 DOI: 10.1016/j.bj.2024.100745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 05/02/2024] [Accepted: 05/05/2024] [Indexed: 05/13/2024] Open
Abstract
Ribonucleoside modifications comprising the epitranscriptome are present in all organisms and all forms of RNA, including mRNA, rRNA and tRNA, the three major RNA components of the translational machinery. Of these, tRNA is the most heavily modified and the tRNA epitranscriptome has the greatest diversity of modifications. In addition to their roles in tRNA biogenesis, quality control, structure, cleavage, and codon recognition, tRNA modifications have been shown to regulate gene expression post-transcriptionally in prokaryotes and eukaryotes, including humans. However, studies investigating the impact of tRNA modifications on gene expression in the malaria parasite Plasmodium falciparum are currently scarce. Current evidence shows that the parasite has a limited capacity for transcriptional control, which points to a heavier reliance on strategies for posttranscriptional regulation such as tRNA epitranscriptome reprogramming. This review addresses the known functions of tRNA modifications in the biology of P. falciparum while highlighting the potential therapeutic opportunities and the value of using P. falciparum as a model organism for addressing several open questions related to the tRNA epitranscriptome.
Collapse
Affiliation(s)
- Benjamin Sian Teck Lee
- Antimicrobial Resistance IRG, Singapore MIT Alliance for Research and Technology, Singapore
| | - Ameya Sinha
- Antimicrobial Resistance IRG, Singapore MIT Alliance for Research and Technology, Singapore;; School of Biological Sciences, Nanyang Technological University, Singapore
| | - Peter Dedon
- Antimicrobial Resistance IRG, Singapore MIT Alliance for Research and Technology, Singapore;; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA USA.
| | - Peter Preiser
- Antimicrobial Resistance IRG, Singapore MIT Alliance for Research and Technology, Singapore;; School of Biological Sciences, Nanyang Technological University, Singapore;.
| |
Collapse
|
2
|
Reyser T, Paloque L, Augereau JM, Di Stefano L, Benoit-Vical F. Epigenetic regulation as a therapeutic target in the malaria parasite Plasmodium falciparum. Malar J 2024; 23:44. [PMID: 38347549 PMCID: PMC10863139 DOI: 10.1186/s12936-024-04855-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 01/18/2024] [Indexed: 02/15/2024] Open
Abstract
Over the past thirty years, epigenetic regulation of gene expression has gained increasing interest as it was shown to be implicated in illnesses ranging from cancers to parasitic diseases. In the malaria parasite, epigenetics was shown to be involved in several key steps of the complex life cycle of Plasmodium, among which asexual development and sexual commitment, but also in major biological processes like immune evasion, response to environmental changes or DNA repair. Because epigenetics plays such paramount roles in the Plasmodium parasite, enzymes involved in these regulating pathways represent a reservoir of potential therapeutic targets. This review focuses on epigenetic regulatory processes and their effectors in the malaria parasite, as well as the inhibitors of epigenetic pathways and their potential as new anti-malarial drugs. Such types of drugs could be formidable tools that may contribute to malaria eradication in a context of widespread resistance to conventional anti-malarials.
Collapse
Affiliation(s)
- Thibaud Reyser
- LCC-CNRS, Laboratoire de Chimie de Coordination, CNRS, Université de Toulouse, Toulouse, France
- MAAP, Inserm ERL 1289, Team "New Antiplasmodial Molecules and Pharmacological Approaches", Toulouse, France
- Institut de Pharmacologie et de Biologie Structurale, IPBS, CNRS, UPS, Université de Toulouse, Toulouse, France
| | - Lucie Paloque
- LCC-CNRS, Laboratoire de Chimie de Coordination, CNRS, Université de Toulouse, Toulouse, France
- MAAP, Inserm ERL 1289, Team "New Antiplasmodial Molecules and Pharmacological Approaches", Toulouse, France
- Institut de Pharmacologie et de Biologie Structurale, IPBS, CNRS, UPS, Université de Toulouse, Toulouse, France
| | - Jean-Michel Augereau
- LCC-CNRS, Laboratoire de Chimie de Coordination, CNRS, Université de Toulouse, Toulouse, France
- MAAP, Inserm ERL 1289, Team "New Antiplasmodial Molecules and Pharmacological Approaches", Toulouse, France
- Institut de Pharmacologie et de Biologie Structurale, IPBS, CNRS, UPS, Université de Toulouse, Toulouse, France
| | - Luisa Di Stefano
- MCD, Centre de Biologie Intégrative (CBI), CNRS, UPS, Université de Toulouse, Toulouse, France
| | - Françoise Benoit-Vical
- LCC-CNRS, Laboratoire de Chimie de Coordination, CNRS, Université de Toulouse, Toulouse, France.
- MAAP, Inserm ERL 1289, Team "New Antiplasmodial Molecules and Pharmacological Approaches", Toulouse, France.
- Institut de Pharmacologie et de Biologie Structurale, IPBS, CNRS, UPS, Université de Toulouse, Toulouse, France.
| |
Collapse
|
3
|
Sah RK, Anand S, Dar W, Jain R, Kumari G, Madan E, Saini M, Gupta A, Joshi N, Hada RS, Gupta N, Pati S, Singh S. Host-Erythrocytic Sphingosine-1-Phosphate Regulates Plasmodium Histone Deacetylase Activity and Exhibits Epigenetic Control over Cell Death and Differentiation. Microbiol Spectr 2023; 11:e0276622. [PMID: 36744922 PMCID: PMC10100792 DOI: 10.1128/spectrum.02766-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 01/08/2023] [Indexed: 02/07/2023] Open
Abstract
The evolution of resistance to practically all antimalarial drugs poses a challenge to the current malaria elimination and eradication efforts. Given that the epigenome of Plasmodium falciparum governs several crucial parasite functions, pharmaceutical interventions with transmission-blocking potential that target epigenetic molecular markers and regulatory mechanisms are likely to encounter drug resistance. In the malaria parasite, histone deacetylases (HDACs) are essential epigenetic modulators that regulate cellular transcriptional rearrangements, notably the molecular mechanisms underlying parasite proliferation and differentiation. We establish "lipid sequestration" as a mechanism by which sphingolipids, specifically Sphingosine-1-Phosphate (S1P) (a metabolic product of Sphingosine Kinase 1 [SphK-1]), regulate epigenetic reprogramming in the parasite by interacting with, and modulating, the histone-deacetylation activity of PfHDAC-1, thereby regulating Plasmodium pathogenesis. Furthermore, we demonstrate that altering host S1P levels with PF-543, a potent and selective Sphk-1 inhibitor, dysregulates PfHDAC-1 activity, resulting in a significant increase in the global histone acetylation signals and, consequently, transcriptional modulation of genes associated with gametocytogenesis, virulence, and proliferation. Our findings point to a hitherto unrecognized functional role for host S1P-mediated sphingolipid signaling in modulating PfHDAC-1's enzymatic activity and, as a result, the parasite's dynamic genome-wide transcriptional patterns. The epigenetic regulation of parasite proliferation and sexual differentiation offers a novel approach for developing host-targeted therapeutics to combat malaria resistance to conventional regimens. IMPORTANCE Sphingolipid is an 18-carbon amino-alcohol-containing lipid with a sphingosine backbone, which when phosphorylated by sphingosine kinase 1 (SphK-1), generates sphingosine-1-phosphate (S1P), an essential lipid signaling molecule. Dysregulation of S1P function has been observed in a variety of pathologies, including severe malaria. The malaria parasite Plasmodium acquires a host S1P pool for its growth and survival. Here, we describe the molecular attuning of histone deacetylase-1 (PfHDAC-1), a crucial epigenetic modulator that contributes to the establishment of epigenetic chromatin states and parasite survival, in response to S1P binding. Our findings highlight the host lipid-mediated epigenetic regulation of malaria parasite key genes.
Collapse
Affiliation(s)
- Raj Kumar Sah
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Sakshi Anand
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Waseem Dar
- School of Natural Sciences, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Ravi Jain
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Geeta Kumari
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Evanka Madan
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Monika Saini
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
- School of Natural Sciences, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Aashima Gupta
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Nishant Joshi
- School of Natural Sciences, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Rahul Singh Hada
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
- School of Natural Sciences, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Nutan Gupta
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Soumya Pati
- School of Natural Sciences, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
4
|
PfARID Regulates P. falciparum Malaria Parasite Male Gametogenesis and Female Fertility and Is Critical for Parasite Transmission to the Mosquito Vector. mBio 2022; 13:e0057822. [PMID: 35638735 PMCID: PMC9239086 DOI: 10.1128/mbio.00578-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sexual reproduction of Plasmodium falciparum parasites is critical to the spread of malaria in the human population. The factors that regulate gene expression underlying formation of fertilization-competent gametes, however, remain unknown. Here, we report that P. falciparum expresses a protein with an AT-rich interaction domain (ARID) which, in other organisms, is part of chromatin remodeling complexes. P. falciparum ARID (PfARID) localized to the parasite nucleus and is critical for the formation of male gametes and fertility of female gametes. PfARID gene deletion (Pfarid–) gametocytes showed downregulation of gene expression important for gametogenesis, antigenic variation, and cell signaling and for parasite development in the mosquito. Our study identifies PfARID as a critical nuclear protein involved in regulating the gene expression landscape of mature gametocytes. This establishes fertility and also prepares the parasite for postfertilization events that are essential for infection of the mosquito vector.
Collapse
|
5
|
Singh G, Gupta D. In-Silico Functional Annotation of Plasmodium falciparum Hypothetical Proteins to Identify Novel Drug Targets. Front Genet 2022; 13:821516. [PMID: 35444689 PMCID: PMC9013929 DOI: 10.3389/fgene.2022.821516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 03/07/2022] [Indexed: 11/16/2022] Open
Abstract
Plasmodium falciparum is one of the plasmodium species responsible for the majority of life-threatening malaria cases. The current antimalarial therapies are becoming less effective due to growing drug resistance, leading to the urgent requirement for alternative and more effective antimalarial drugs or vaccines. To facilitate the novel drug discovery or vaccine development efforts, recent advances in sequencing technologies provide valuable information about the whole genome of the parasite, yet a lot more needs to be deciphered due to its incomplete proteome annotation. Surprisingly, out of the 5,389 proteins currently annotated in the Plasmodium falciparum 3D7 strain, 1,626 proteins (∼30% data) are annotated as hypothetical proteins. In parasite genomic studies, the challenge to annotate hypothetical proteins is often ignored, which may obscure the crucial information related to the pathogenicity of the parasite. In this study, we attempt to characterize hypothetical proteins of the parasite to identify novel drug targets using a computational pipeline. The study reveals that out of the overall pool of the hypothetical proteins, 266 proteins have conserved functional signatures. Furthermore, the pathway analysis of these proteins revealed that 23 proteins have an essential role in various biochemical, signalling and metabolic pathways. Additionally, all the proteins (266) were subjected to computational structure analysis. We could successfully model 11 proteins. We validated and checked the structural stability of the models by performing molecular dynamics simulation. Interestingly, eight proteins show stable conformations, and seven proteins are specific for Plasmodium falciparum, based on homology analysis. Lastly, mapping the seven shortlisted hypothetical proteins on the Plasmodium falciparum protein-protein interaction network revealed 3,299 nodes and 2,750,692 edges. Our study revealed interesting functional details of seven hypothetical proteins of the parasite, which help learn more about the less-studied molecules and their interactions, providing valuable clues to unravel the role of these proteins via future experimental validation.
Collapse
Affiliation(s)
- Gagandeep Singh
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Dinesh Gupta
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| |
Collapse
|
6
|
Functional characterization of 5' UTR cis-acting sequence elements that modulate translational efficiency in Plasmodium falciparum and humans. Malar J 2022; 21:15. [PMID: 34991611 PMCID: PMC8739713 DOI: 10.1186/s12936-021-04024-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/14/2021] [Indexed: 11/10/2022] Open
Abstract
Background The eukaryotic parasite Plasmodium falciparum causes millions of malarial infections annually while drug resistance to common anti-malarials is further confounding eradication efforts. Translation is an attractive therapeutic target that will benefit from a deeper mechanistic understanding. As the rate limiting step of translation, initiation is a primary driver of translational efficiency. It is a complex process regulated by both cis and trans acting factors, providing numerous potential targets. Relative to model organisms and humans, P. falciparum mRNAs feature unusual 5′ untranslated regions suggesting cis-acting sequence complexity in this parasite may act to tune levels of protein synthesis through their effects on translational efficiency. Methods Here, in vitro translation is deployed to compare the role of cis-acting regulatory sequences in P. falciparum and humans. Using parasite mRNAs with high or low translational efficiency, the presence, position, and termination status of upstream “AUG”s, in addition to the base composition of the 5′ untranslated regions, were characterized. Results The density of upstream “AUG”s differed significantly among the most and least efficiently translated genes in P. falciparum, as did the average “GC” content of the 5′ untranslated regions. Using exemplars from highly translated and poorly translated mRNAs, multiple putative upstream elements were interrogated for impact on translational efficiency. Upstream “AUG”s were found to repress translation to varying degrees, depending on their position and context, while combinations of upstream “AUG”s had non-additive effects. The base composition of the 5′ untranslated regions also impacted translation, but to a lesser degree. Surprisingly, the effects of cis-acting sequences were remarkably conserved between P. falciparum and humans. Conclusions While translational regulation is inherently complex, this work contributes toward a more comprehensive understanding of parasite and human translational regulation by examining the impact of discrete cis-acting features, acting alone or in context. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04024-2.
Collapse
|
7
|
Tajiri M. Phage Display Screening for Alba Superfamily Proteins from the Human Malaria Parasite, Plasmodium falciparum Reveals a High Level of Association with Protein Modification Pathways and Hints at New Drug Targets. Acta Parasitol 2021; 66:844-850. [PMID: 33559027 DOI: 10.1007/s11686-021-00339-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 01/19/2021] [Indexed: 11/25/2022]
Abstract
PURPOSE A 2016 study estimated that over 3 billion people are currently at risk of contracting malaria. Although a wide variety of medications are available to treat malaria, the parasites have started to exhibit resistance to many commonly used therapeutics necessitating a push for new investigations to identify novel drug targets. METHODS In this study, nucleic acid-binding Alba superfamily proteins of the human malaria parasite, Plasmodium falciparum were investigated to identify interacting protein motifs. A high-throughput molecular screening technique, phage display, coupled with next-generation sequencing was applied to assess large data sets. RESULTS Four P. falciparum Alba proteins were used for screening which appear to have distinct roles in parasite biology based on the results of this work. The majority of the peptide motifs identified from phage display were involved in post-translational modification pathways, thus suggesting that parasite-specific gene regulatory mechanisms are involved which could serve as drug targets for novel therapeutics. CONCLUSION This study found 18 peptide motifs which potentially have strong interactions with one or more of the Alba superfamily proteins from P. falciparum. Considering the large fraction of post-translational modification-related peptide motifs identified from this work, one or more of the protein modification pathways could serve as a good target for malaria treatment.
Collapse
Affiliation(s)
- Momoko Tajiri
- Department of Chemistry, Michigan Technological University, Houghton, MI, 49931-1295, USA.
| |
Collapse
|
8
|
Peculiarities of Plasmodium falciparum Gene Regulation and Chromatin Structure. Int J Mol Sci 2021; 22:ijms22105168. [PMID: 34068393 PMCID: PMC8153576 DOI: 10.3390/ijms22105168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/14/2022] Open
Abstract
The highly complex life cycle of the human malaria parasite, Plasmodium falciparum, is based on an orchestrated and tightly regulated gene expression program. In general, eukaryotic transcription regulation is determined by a combination of sequence-specific transcription factors binding to regulatory DNA elements and the packaging of DNA into chromatin as an additional layer. The accessibility of regulatory DNA elements is controlled by the nucleosome occupancy and changes of their positions by an active process called nucleosome remodeling. These epigenetic mechanisms are poorly explored in P. falciparum. The parasite genome is characterized by an extraordinarily high AT-content and the distinct architecture of functional elements, and chromatin-related proteins also exhibit high sequence divergence compared to other eukaryotes. Together with the distinct biochemical properties of nucleosomes, these features suggest substantial differences in chromatin-dependent regulation. Here, we highlight the peculiarities of epigenetic mechanisms in P. falciparum, addressing chromatin structure and dynamics with respect to their impact on transcriptional control. We focus on the specialized chromatin remodeling enzymes and discuss their essential function in P. falciparum gene regulation.
Collapse
|
9
|
Connacher J, Josling GA, Orchard LM, Reader J, Llinás M, Birkholtz LM. H3K36 methylation reprograms gene expression to drive early gametocyte development in Plasmodium falciparum. Epigenetics Chromatin 2021; 14:19. [PMID: 33794978 PMCID: PMC8017609 DOI: 10.1186/s13072-021-00393-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/26/2021] [Indexed: 12/12/2022] Open
Abstract
Background The Plasmodium sexual gametocyte stages are the only transmissible form of the malaria parasite and are thus responsible for the continued transmission of the disease. Gametocytes undergo extensive functional and morphological changes from commitment to maturity, directed by an equally extensive control program. However, the processes that drive the differentiation and development of the gametocyte post-commitment, remain largely unexplored. A previous study reported enrichment of H3K36 di- and tri-methylated (H3K36me2&3) histones in early-stage gametocytes. Using chromatin immunoprecipitation followed by high-throughput sequencing, we identify a stage-specific association between these repressive histone modifications and transcriptional reprogramming that define a stage II gametocyte transition point. Results Here, we show that H3K36me2 and H3K36me3 from stage II gametocytes are associated with repression of genes involved in asexual proliferation and sexual commitment, indicating that H3K36me2&3-mediated repression of such genes is essential to the transition from early gametocyte differentiation to intermediate development. Importantly, we show that the gene encoding the transcription factor AP2-G as commitment master regulator is enriched with H3K36me2&3 and actively repressed in stage II gametocytes, providing the first evidence of ap2-g gene repression in post-commitment gametocytes. Lastly, we associate the enhanced potency of the pan-selective Jumonji inhibitor JIB-04 in gametocytes with the inhibition of histone demethylation including H3K36me2&3 and a disruption of normal transcriptional programs. Conclusions Taken together, our results provide the first description of an association between global gene expression reprogramming and histone post-translational modifications during P. falciparum early sexual development. The stage II gametocyte-specific abundance of H3K36me2&3 manifests predominantly as an independent regulatory mechanism targeted towards genes that are repressed post-commitment. H3K36me2&3-associated repression of genes is therefore involved in key transcriptional shifts that accompany the transition from early gametocyte differentiation to intermediate development. Supplementary Information The online version contains supplementary material available at 10.1186/s13072-021-00393-9.
Collapse
Affiliation(s)
- Jessica Connacher
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Gabrielle A Josling
- Department of Biochemistry & Molecular Biology and the Huck Center for Malaria Research, Pennsylvania State University, University Park, PA, 16802, USA
| | - Lindsey M Orchard
- Department of Biochemistry & Molecular Biology and the Huck Center for Malaria Research, Pennsylvania State University, University Park, PA, 16802, USA
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Manuel Llinás
- Department of Biochemistry & Molecular Biology and the Huck Center for Malaria Research, Pennsylvania State University, University Park, PA, 16802, USA.,Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA
| | - Lyn-Marié Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa.
| |
Collapse
|
10
|
Direct Nanopore Sequencing of mRNA Reveals Landscape of Transcript Isoforms in Apicomplexan Parasites. mSystems 2021; 6:6/2/e01081-20. [PMID: 33688018 PMCID: PMC8561664 DOI: 10.1128/msystems.01081-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Alternative splicing is a widespread phenomenon in metazoans by which single genes are able to produce multiple isoforms of the gene product. However, this has been poorly characterized in apicomplexans, a major phylum of some of the most important global parasites. Efforts have been hampered by atypical transcriptomic features, such as the high AU content of Plasmodium RNA, but also the limitations of short-read sequencing in deciphering complex splicing events. In this study, we utilized the long read direct RNA sequencing platform developed by Oxford Nanopore Technologies to survey the alternative splicing landscape of Toxoplasma gondii and Plasmodium falciparum. We find that while native RNA sequencing has a reduced throughput, it allows us to obtain full-length or nearly full-length transcripts with comparable quantification to Illumina sequencing. By comparing these data with available gene models, we find widespread alternative splicing, particularly intron retention, in these parasites. Most of these transcripts contain premature stop codons, suggesting that in these parasites, alternative splicing represents a pathway to transcriptomic diversity, rather than expanding proteomic diversity. Moreover, alternative splicing rates are comparable between parasites, suggesting a shared splicing machinery, despite notable transcriptomic differences between the parasites. This study highlights a strategy in using long-read sequencing to understand splicing events at the whole-transcript level and has implications in the future interpretation of transcriptome sequencing studies. IMPORTANCE We have used a novel nanopore sequencing technology to directly analyze parasite transcriptomes. The very long reads of this technology reveal the full-length genes of the parasites that cause malaria and toxoplasmosis. Gene transcripts must be processed in a process called splicing before they can be translated to protein. Our analysis reveals that these parasites very frequently only partially process their gene products, in a manner that departs dramatically from their human hosts.
Collapse
|
11
|
Potluri V, Shandil RK, Gavara R, Sambasivam G, Campo B, Wittlin S, Narayanan S. Discovery of FNDR-20123, a histone deacetylase inhibitor for the treatment of Plasmodium falciparum malaria. Malar J 2020; 19:365. [PMID: 33046062 PMCID: PMC7549214 DOI: 10.1186/s12936-020-03421-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 09/20/2020] [Indexed: 12/14/2022] Open
Abstract
Background Emergence of anti-malarial drug resistance and perpetual increase in malaria incidence necessitates the development of novel anti-malarials. Histone deacetylases (HDAC) has been shown to be a promising target for malaria, despite this, there are no HDAC inhibitors in clinical trials for malaria treatment. This can be attributed to the poor pharmacokinetics, bioavailability and selectivity of the HDAC inhibitors. Methods A collection of HDAC inhibitors were screened for anti-malarial activity, and the best candidate was profiled in parasite-killing kinetics, growth inhibition of sensitive and multi-drug resistant (MDR) strains and against gametocytes. Absorption, distribution, metabolism and excretion pharmacokinetics (ADME-PK) parameters of FNDR-20123 were determined, and in vivo efficacy was studied in a mouse model for Plasmodium falciparum infection. Results A compound library of HDAC inhibitors (180 in number) was screened for anti-malarial activity, of which FNDR-20123 was the most potent candidate. The compound had been shown to inhibit Plasmodium HDAC with IC50 of 31 nM and human HDAC with IC50 of 3 nM. The IC50 obtained for P. falciparum in asexual blood-stage assay was 42 nM. When compared to atovaquone and pyrimethamine, the killing profiles of FNDR-20123 were better than atovaquone and comparable to pyrimethamine. The IC50 values for the growth inhibition of sensitive and MDR strains were similar, indicating that there is no cross-resistance and a low risk of resistance development. The selected compound was also active against gametocytes, indicating a potential for transmission control: IC50 values being 190 nM for male and > 5 µM for female gametocytes. FNDR-20123 is a stable candidate in human/mouse/rat liver microsomes (> 75% remaining post 2-h incubation), exhibits low plasma protein binding (57% in humans) with no human Ether-à-go–go-Related Gene (hERG) liability (> 100 µM), and does not inhibit any of the cytochrome P450 (CYP) isoforms tested (IC50 > 25 µM). It also shows negligible cytotoxicity to HepG-2 and THP-1 cell lines. The oral pharmacokinetics in rats at 100 mg/kg body weight shows good exposures (Cmax = 1.1 µM) and half-life (T1/2 = 5.5 h). Furthermore, a 14-day toxicokinetic study at 100 mg/kg daily dose did not show any abnormality in body weight or gross organ pathology. FNDR-20123 is also able to reduce parasitaemia significantly in a mouse model for P. falciparum infection when dosed orally and subcutaneously. Conclusion FNDR-20123 may be a suitable candidate for the treatment of malaria, which can be further developed.
Collapse
Affiliation(s)
- Vijay Potluri
- Foundation for Neglected Disease Research, Bengaluru, India
| | | | - R Gavara
- Anthem Biosciences Private Limited, Bengaluru, India
| | | | - Brice Campo
- Medicines for Malaria Venture, Geneva, Switzerland
| | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | |
Collapse
|
12
|
Coetzee N, von Grüning H, Opperman D, van der Watt M, Reader J, Birkholtz LM. Epigenetic inhibitors target multiple stages of Plasmodium falciparum parasites. Sci Rep 2020; 10:2355. [PMID: 32047203 PMCID: PMC7012883 DOI: 10.1038/s41598-020-59298-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 12/16/2019] [Indexed: 12/22/2022] Open
Abstract
The epigenome of the malaria parasite, Plasmodium falciparum, is associated with regulation of various essential processes in the parasite including control of proliferation during asexual development as well as control of sexual differentiation. The unusual nature of the epigenome has prompted investigations into the potential to target epigenetic modulators with novel chemotypes. Here, we explored the diversity within a library of 95 compounds, active against various epigenetic modifiers in cancerous cells, for activity against multiple stages of P. falciparum development. We show that P. falciparum is differentially susceptible to epigenetic perturbation during both asexual and sexual development, with early stage gametocytes particularly sensitive to epi-drugs targeting both histone and non-histone epigenetic modifiers. Moreover, 5 compounds targeting histone acetylation and methylation show potent multistage activity against asexual parasites, early and late stage gametocytes, with transmission-blocking potential. Overall, these results warrant further examination of the potential antimalarial properties of these hit compounds.
Collapse
Affiliation(s)
- Nanika Coetzee
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Hilde von Grüning
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Daniel Opperman
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Mariette van der Watt
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Lyn-Marié Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa.
| |
Collapse
|
13
|
Wang WF, Zhang YL. PfSWIB, a potential chromatin regulator for var gene regulation and parasite development in Plasmodium falciparum. Parasit Vectors 2020; 13:48. [PMID: 32019597 PMCID: PMC7001229 DOI: 10.1186/s13071-020-3918-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 01/29/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Various transcription factors are involved in the process of mutually exclusive expression and clonal variation of the Plasmodium multigene (var) family. Recent studies revealed that a P. falciparum SWI/SNF-related matrix-associated actin-dependent regulator of chromatin (PfSWIB) might trigger stage-specific programmed cell death (PCD), and was not only crucial for the survival and development of parasite, but also had profound effects on the parasite by interacting with other unknown proteins. However, it remains unclear whether PfSIWB is involved in transcriptional regulation of this virulence gene and its functional properties. METHODS A conditional knockdown system "PfSWIB-FKBP-LID" was introduced to the parasite clone 3D7, and an integrated parasite line "PfSWIB-HA-FKBP-LID" was obtained by drug cycling and clone screening. Growth curve analysis (GCA) was performed to investigate the growth and development of different parasite lines during 96 h in vitro culturing, by assessing parasitemia. Finally, we performed qPCR assays to detect var gene expression profiling in various comparison groups, as well as the mutually exclusive expression pattern of the var genes within a single 48 h life-cycle of P. falciparum in different parasite lines. In addition, RNA-seq was applied to analyze the var gene expression in different lines. RESULTS GCA revealed that conditional knockdown of PfSWIB could interfere with the growth and development of P. falciparum. The parasitemia of PfSWIB∆ showed a significant decline at 96 h during in vitro culture compared with the PfSWIB and 3D7 lines (P < 0.0001). qPCR and RNA-seq analysis confirmed that depletion of PfSWIB not only silences upsA, upsC and partial upsB var genes, as well as removes the silencing of partial upsB var genes at the ring stage in PfSWIB∆ line, but also leads to aberrant expression of upsA and partial upsB/upsC var genes at the mature stage of P. falciparum, during a single 48-h life-cycle. CONCLUSIONS We demonstrated that PfSWIB was involved in the process of clonal variation in var gene expression, and crucial for the survival and development of Plasmodium parasite. These findings could provide better understanding of the mechanism and function of PfSWIB contributing to the pathogenesis in malaria parasites.
Collapse
Affiliation(s)
- Wei-Feng Wang
- Central Laboratory, Shanghai Tenth People's Hospital, Tongji University, Shanghai, 200072, China.,Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, 1239 Siping Road, Shanghai, 200092, China
| | - Yi-Long Zhang
- Department of Tropical Diseases, Faculty of Naval Medicine, Second Military Medical University, Shanghai, 200433, China. .,Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, 1239 Siping Road, Shanghai, 200092, China.
| |
Collapse
|
14
|
van Biljon R, van Wyk R, Painter HJ, Orchard L, Reader J, Niemand J, Llinás M, Birkholtz LM. Hierarchical transcriptional control regulates Plasmodium falciparum sexual differentiation. BMC Genomics 2019; 20:920. [PMID: 31795940 PMCID: PMC6889441 DOI: 10.1186/s12864-019-6322-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/22/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Malaria pathogenesis relies on sexual gametocyte forms of the malaria parasite to be transmitted between the infected human and the mosquito host but the molecular mechanisms controlling gametocytogenesis remains poorly understood. Here we provide a high-resolution transcriptome of Plasmodium falciparum as it commits to and develops through gametocytogenesis. RESULTS The gametocyte-associated transcriptome is significantly different from that of the asexual parasites, with dynamic gene expression shifts characterizing early, intermediate and late-stage gametocyte development and results in differential timing for sex-specific transcripts. The transcriptional dynamics suggest strict transcriptional control during gametocytogenesis in P. falciparum, which we propose is mediated by putative regulators including epigenetic mechanisms (driving active repression of proliferation-associated processes) and a cascade-like expression of ApiAP2 transcription factors. CONCLUSIONS The gametocyte transcriptome serves as the blueprint for sexual differentiation and will be a rich resource for future functional studies on this critical stage of Plasmodium development, as the intraerythrocytic transcriptome has been for our understanding of the asexual cycle.
Collapse
Affiliation(s)
- Riëtte van Biljon
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
- Department of Biochemistry & Molecular Biology and the Huck Center for Malaria Research, Pennsylvania State University, University Park, PA, 16802, USA
| | - Roelof van Wyk
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Heather J Painter
- Department of Biochemistry & Molecular Biology, the Huck Center for Malaria Research, University Park, PA, 16802, USA
- Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Review, U.S. Food & Drug Administration, Silver Spring, MD, 20993, USA
| | - Lindsey Orchard
- Department of Biochemistry & Molecular Biology, the Huck Center for Malaria Research, University Park, PA, 16802, USA
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Jandeli Niemand
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa
| | - Manuel Llinás
- Department of Biochemistry & Molecular Biology, the Huck Center for Malaria Research, University Park, PA, 16802, USA
- Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Private Bag x20, Hatfield, 0028, South Africa.
| |
Collapse
|
15
|
Histone deacetylase inhibitors with high in vitro activities against Plasmodium falciparum isolates collected from Gabonese children and adults. Sci Rep 2019; 9:17336. [PMID: 31758015 PMCID: PMC6874535 DOI: 10.1038/s41598-019-53912-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/04/2019] [Indexed: 01/25/2023] Open
Abstract
Histone deacetylase (HDAC) enzymes are targets for the development of antimalarial drugs with a different mode of action to established antimalarials. Broad-spectrum HDAC-inhibitors show high potency against Plasmodium falciparum, but displayed some toxicity towards human cells. Inhibitors of human HDAC6 are new drug candidates with supposed reduced toxicity to human cells and favorable activities against laboratory P. falciparum strains. We investigated the potency of 12 peptoid-based HDAC-inhibitors against asexual stages of P. falciparum clinical isolates. Parasites representing different genetic backgrounds were isolated from adults and children with uncomplicated malaria in Gabon. Clinical studies on (non-HDAC-inhibitors) antimalarials, moreover, found lower drug efficacy in children, mainly attributed to acquired immunity with age in endemic areas. Therefore, we compared the in vitro sensitivity profiles of adult- and child-derived isolates to antimalarials (HDAC and standard drugs). All HDAC-inhibitors showed 50% inhibitory concentrations at nanomolar ranges with higher activities than the FDA approved reference HDAC-inhibitor SAHA. We propose peptoid-based HDAC6-inhibitors to be lead structures for further development as antimalarial chemotherapeutics. Our results further suggest no differences in activity of the tested antimalarials between P. falciparum parasites isolated from children and adults.
Collapse
|
16
|
Toenhake CG, Bártfai R. What functional genomics has taught us about transcriptional regulation in malaria parasites. Brief Funct Genomics 2019; 18:290-301. [PMID: 31220867 PMCID: PMC6859821 DOI: 10.1093/bfgp/elz004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 02/08/2019] [Accepted: 03/14/2019] [Indexed: 12/16/2022] Open
Abstract
Malaria parasites are characterized by a complex life cycle that is accompanied by dynamic gene expression patterns. The factors and mechanisms that regulate gene expression in these parasites have been searched for even before the advent of next generation sequencing technologies. Functional genomics approaches have substantially boosted this area of research and have yielded significant insights into the interplay between epigenetic, transcriptional and post-transcriptional mechanisms. Recently, considerable progress has been made in identifying sequence-specific transcription factors and DNA-encoded regulatory elements. Here, we review the insights obtained from these efforts including the characterization of core promoters, the involvement of sequence-specific transcription factors in life cycle progression and the mapping of gene regulatory elements. Furthermore, we discuss recent developments in the field of functional genomics and how they might contribute to further characterization of this complex gene regulatory network.
Collapse
Affiliation(s)
- Christa G Toenhake
- Radboud University, Faculty of Science, Department of Molecular Biology, Nijmegen, the Netherlands
| | - Richárd Bártfai
- Radboud University, Faculty of Science, Department of Molecular Biology, Nijmegen, the Netherlands
| |
Collapse
|
17
|
Engel JA, Norris EL, Gilson P, Przyborski J, Shonhai A, Blatch GL, Skinner-Adams TS, Gorman J, Headlam M, Andrews KT. Proteomic analysis of Plasmodium falciparum histone deacetylase 1 complex proteins. Exp Parasitol 2019; 198:7-16. [PMID: 30682336 DOI: 10.1016/j.exppara.2019.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 12/01/2018] [Accepted: 01/20/2019] [Indexed: 01/12/2023]
Abstract
Plasmodium falciparum histone deacetylases (PfHDACs) are an important class of epigenetic regulators that alter protein lysine acetylation, contributing to regulation of gene expression and normal parasite growth and development. PfHDACs are therefore under investigation as drug targets for malaria. Despite this, our understanding of the biological roles of these enzymes is only just beginning to emerge. In higher eukaryotes, HDACs function as part of multi-protein complexes and act on both histone and non-histone substrates. Here, we present a proteomics analysis of PfHDAC1 immunoprecipitates, identifying 26 putative P. falciparum complex proteins in trophozoite-stage asexual intraerythrocytic parasites. The co-migration of two of these (P. falciparum heat shock proteins 70-1 and 90) with PfHDAC1 was validated using Blue Native PAGE combined with Western blot. These data provide a snapshot of possible PfHDAC1 interactions and a starting point for future studies focused on elucidating the broader function of PfHDACs in Plasmodium parasites.
Collapse
Affiliation(s)
- Jessica A Engel
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia
| | - Emma L Norris
- QIMR Berghofer Medical Research Institute, Queensland, Australia
| | - Paul Gilson
- Burnet Institute, Monash University, Victoria, Australia
| | - Jude Przyborski
- Centre of Infectious Diseases, Parasitology, University Hospital Heidelberg, Germany
| | - Addmore Shonhai
- Biochemistry Department, University of Venda, Thohoyandou, South Africa
| | - Gregory L Blatch
- The Vice Chancellery, The University of Notre Dame Australia, Fremantle, WA, Australia
| | - Tina S Skinner-Adams
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia
| | - Jeffrey Gorman
- QIMR Berghofer Medical Research Institute, Queensland, Australia
| | | | - Katherine T Andrews
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia.
| |
Collapse
|
18
|
Ng CS, Sinha A, Aniweh Y, Nah Q, Babu IR, Gu C, Chionh YH, Dedon PC, Preiser PR. tRNA epitranscriptomics and biased codon are linked to proteome expression in Plasmodium falciparum. Mol Syst Biol 2018; 14:e8009. [PMID: 30287681 PMCID: PMC6171970 DOI: 10.15252/msb.20178009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 08/09/2018] [Accepted: 09/07/2018] [Indexed: 12/24/2022] Open
Abstract
Among components of the translational machinery, ribonucleoside modifications on tRNAs are emerging as critical regulators of cell physiology and stress response. Here, we demonstrate highly coordinated behavior of the repertoire of tRNA modifications of Plasmodium falciparum throughout the intra-erythrocytic developmental cycle (IDC). We observed both a synchronized increase in 22 of 28 modifications from ring to trophozoite stage, consistent with tRNA maturation during translational up-regulation, and asynchronous changes in six modifications. Quantitative analysis of ~2,100 proteins across the IDC revealed that up- and down-regulated proteins in late but not early stages have a marked codon bias that directly correlates with parallel changes in tRNA modifications and enhanced translational efficiency. We thus propose a model in which tRNA modifications modulate the abundance of stage-specific proteins by enhancing translation efficiency of codon-biased transcripts for critical genes. These findings reveal novel epitranscriptomic and translational control mechanisms in the development and pathogenesis of Plasmodium parasites.
Collapse
Affiliation(s)
- Chee Sheng Ng
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ameya Sinha
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yaw Aniweh
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| | - Qianhui Nah
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
| | - Indrakanti Ramesh Babu
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Chen Gu
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yok Hian Chionh
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
- Department of Microbiology and Immunology Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore City, Singapore
| | - Peter C Dedon
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Center for Environmental Health Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Peter R Preiser
- Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore City, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
| |
Collapse
|
19
|
Molnár P, Marton L, Izrael R, Pálinkás HL, Vértessy BG. Uracil moieties in Plasmodium falciparum genomic DNA. FEBS Open Bio 2018; 8:1763-1772. [PMID: 30410856 PMCID: PMC6212640 DOI: 10.1002/2211-5463.12458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/11/2018] [Accepted: 05/21/2018] [Indexed: 11/12/2022] Open
Abstract
Plasmodium falciparum parasites undergo multiple genome duplication events during their development. Within the intraerythrocytic stages, parasites encounter an oxidative environment and DNA synthesis necessarily proceeds under these circumstances. In addition to these conditions, the extreme AT bias of the P. falciparum genome poses further constraints for DNA synthesis. Taken together, these circumstances may allow appearance of damaged bases in the PlasmodiumDNA. Here, we focus on uracil that may arise in DNA either via oxidative deamination or thymine‐replacing incorporation. We determine the level of uracil at the ring, trophozoite, and schizont intraerythrocytic stages and evaluate the base‐excision repair potential of P. falciparum to deal with uracil‐DNA repair. We find approximately 7–10 uracil per million bases in the different parasite stages. This level is considerably higher than found in other wild‐type organisms from bacteria to mammalian species. Based on a systematic assessment of P. falciparum genome and transcriptome databases, we conclude that uracil‐DNA repair relies on one single uracil‐DNA glycosylase and proceeds through the long‐patch base‐excision repair route. Although potentially efficient, the repair route still leaves considerable level of uracils in parasite DNA, which may contribute to mutation rates in P. falciparum.
Collapse
Affiliation(s)
- Petra Molnár
- Research Centre for Natural Sciences Institute of Enzymology BME-MTA Malaria Research Laboratory Hungarian Academy of Sciences Budapest Hungary.,Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
| | - Lívia Marton
- Research Centre for Natural Sciences Institute of Enzymology BME-MTA Malaria Research Laboratory Hungarian Academy of Sciences Budapest Hungary
| | - Richard Izrael
- Research Centre for Natural Sciences Institute of Enzymology BME-MTA Malaria Research Laboratory Hungarian Academy of Sciences Budapest Hungary.,Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
| | - Hajnalka L Pálinkás
- Research Centre for Natural Sciences Institute of Enzymology BME-MTA Malaria Research Laboratory Hungarian Academy of Sciences Budapest Hungary.,Doctoral School of Multidisciplinary Medical Science University of Szeged Szeged Hungary
| | - Beáta G Vértessy
- Research Centre for Natural Sciences Institute of Enzymology BME-MTA Malaria Research Laboratory Hungarian Academy of Sciences Budapest Hungary.,Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
| |
Collapse
|
20
|
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.
Collapse
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.
| |
Collapse
|
21
|
Sen U, Saxena H, Khurana J, Nayak A, Gupta A. Plasmodium falciparum RUVBL3 protein: a novel DNA modifying enzyme and an interacting partner of essential HAT protein MYST. Sci Rep 2018; 8:10917. [PMID: 30026605 PMCID: PMC6053374 DOI: 10.1038/s41598-018-29137-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/26/2018] [Indexed: 11/09/2022] Open
Abstract
RUVBLs constitute a conserved group of ATPase proteins that play significant role in a variety of cellular processes including transcriptional regulation, cell cycle and DNA damage repair. Three RUVBL homologues, namely, PfRUVBL1, PfRUVBL2 and PfRUVBL3 have been identified in P. falciparum, unlike its eukaryotic counterparts, which have two RUVBL proteins (RUVBL1 & RUVBL2). The present study expands our understanding of PfRUVBL3 protein and thereby basic biology of Plasmodium in general. Here, we have shown that parasite PfRUVBL3 is a true homolog of human/yeast RUVBL2 protein. Our result show that PfRUVBL3 constitutively expresses throughout the stages of intra-erythrocytic cycle (IDC) with varied localization. In addition to ATPase and oligomerization activity, we have for the first time shown that PfRUVBL3 possess DNA cleavage activity which interestingly is dependent on its insertion domain. Furthermore, we have also identified RUVBL3 to be an interacting partner of an essential chromatin remodeling protein PfMYST and together they colocalize with H3K9me1 histone in parasitophorous vacuole during the ring stage of IDC suggesting their potential involvement in chromatin remodeling and gene transcription.
Collapse
Affiliation(s)
- Utsav Sen
- Department of Life Sciences, Shiv Nadar University, Greater Noida, 201314, India
| | - Himani Saxena
- Department of Life Sciences, Shiv Nadar University, Greater Noida, 201314, India
| | - Juhi Khurana
- Department of Life Sciences, Shiv Nadar University, Greater Noida, 201314, India
| | - Akshaykumar Nayak
- Department of Life Sciences, Shiv Nadar University, Greater Noida, 201314, India
| | - Ashish Gupta
- Department of Life Sciences, Shiv Nadar University, Greater Noida, 201314, India.
| |
Collapse
|
22
|
Painter HJ, Chung NC, Sebastian A, Albert I, Storey JD, Llinás M. Genome-wide real-time in vivo transcriptional dynamics during Plasmodium falciparum blood-stage development. Nat Commun 2018; 9:2656. [PMID: 29985403 PMCID: PMC6037754 DOI: 10.1038/s41467-018-04966-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/31/2018] [Indexed: 01/12/2023] Open
Abstract
Genome-wide analysis of transcription in the malaria parasite Plasmodium falciparum has revealed robust variation in steady-state mRNA abundance throughout the 48-h intraerythrocytic developmental cycle (IDC), suggesting that this process is highly dynamic and tightly regulated. Here, we utilize rapid 4-thiouracil (4-TU) incorporation via pyrimidine salvage to specifically label, capture, and quantify newly-synthesized RNA transcripts at every hour throughout the IDC. This high-resolution global analysis of the transcriptome captures the timing and rate of transcription for each newly synthesized mRNA in vivo, revealing active transcription throughout all IDC stages. Using a statistical model to predict the mRNA dynamics contributing to the total mRNA abundance at each timepoint, we find varying degrees of transcription and stabilization for each mRNA corresponding to developmental transitions. Finally, our results provide new insight into co-regulation of mRNAs throughout the IDC through regulatory DNA sequence motifs, thereby expanding our understanding of P. falciparum mRNA dynamics. Transcriptomic analysis often doesn’t differentiate between newly synthesized and stabilized mRNAs. Using rapid 4-thiouracil incorporation, Painter et al. here define genome-wide active transcription throughout Plasmodium blood-stage developmental stages and identify associated regulatory DNA sequence motifs.
Collapse
Affiliation(s)
- Heather J Painter
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.,Huck Center for Malaria Research, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Neo Christopher Chung
- Lewis-Sigler Institute for Integrative Genomics and Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA.,Institute of Informatics, Faculty of Mathematics, Informatics, and Mechanics, University of Warsaw, 02-097 Warsaw, Poland
| | - Aswathy Sebastian
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Istvan Albert
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - John D Storey
- Lewis-Sigler Institute for Integrative Genomics and Department of Molecular Biology, Princeton University, Princeton, NJ, 08544, USA.,Center for Statistics and Machine Learning, Princeton University, Princeton, NJ, 08544, USA
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA. .,Huck Center for Malaria Research, The Pennsylvania State University, University Park, PA, 16802, USA. .,Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
| |
Collapse
|
23
|
Varoquaux N. Unfolding the Genome: The Case Study of P. falciparum. Int J Biostat 2018; 15:ijb-2017-0061. [PMID: 29878883 DOI: 10.1515/ijb-2017-0061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 05/10/2018] [Indexed: 11/15/2022]
Abstract
The development of new ways to probe samples for the three-dimensional (3D) structure of DNA paves the way for in depth and systematic analyses of the genome architecture. 3C-like methods coupled with high-throughput sequencing can now assess physical interactions between pairs of loci in a genome-wide fashion, thus enabling the creation of genome-by-genome contact maps. The spreading of such protocols creates many new opportunities for methodological development: how can we infer 3D models from these contact maps? Can such models help us gain insights into biological processes? Several recent studies applied such protocols to P. falciparum (the deadliest of the five human malaria parasites), assessing its genome organization at different moments of its life cycle. With its small genomic size, fairly simple (yet changing) genomic organization during its lifecyle and strong correlation between chromatin folding and gene expression, this parasite is the ideal case study for applying and developing methods to infer 3D models and use them for downstream analysis. Here, I review a set of methods used to build and analyse three-dimensional models from contact maps data with a special highlight on P. falciparum's genome organization.
Collapse
Affiliation(s)
- Nelle Varoquaux
- Statistics, University of California, Berkeley, 367 Evans Hall, Berkeley, California, USA
- Berkeley Institute for Data Science, 190, Doe libraryBerkeley, United States of America
| |
Collapse
|
24
|
Ávila AR, Cabezas-Cruz A, Gissot M. mRNA export in the apicomplexan parasite Toxoplasma gondii: emerging divergent components of a crucial pathway. Parasit Vectors 2018; 11:62. [PMID: 29370868 PMCID: PMC5785795 DOI: 10.1186/s13071-018-2648-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/15/2018] [Indexed: 01/08/2023] Open
Abstract
Control of gene expression is crucial for parasite survival and is the result of a series of processes that are regulated to permit fine-tuning of gene expression in response to biological changes during the life-cycle of apicomplexan parasites. Control of mRNA nuclear export is a key process in eukaryotic cells but is poorly understood in apicomplexan parasites. Here, we review recent knowledge regarding this process with an emphasis on T. gondii. We describe the presence of divergent orthologs and discuss structural and functional differences in export factors between apicomplexans and other eukaryotic lineages. Undoubtedly, the use of the CRISPR/Cas9 system in high throughput screenings associated with the discovery of mRNA nuclear export complexes by proteomic analysis will contribute to identify these divergent factors. Ligand-based or structure-based strategies may be applied to investigate the potential use of these proteins as targets for new antiprotozoal agents.
Collapse
Affiliation(s)
- Andréa Rodrigues Ávila
- Instituto Carlos Chagas, FIOCRUZ, Rua Algacyr Munhoz Mader, 3775. CIC, Curitiba, PR, 81350-010, Brazil. .,UMR BIPAR, Animal Health Laboratory, ANSES, INRA, ENVA, Maisons Alfort, Cedex, France.
| | - Alexjandro Cabezas-Cruz
- UMR BIPAR, Animal Health Laboratory, ANSES, INRA, ENVA, Maisons Alfort, Cedex, France.,Institute of Parasitology, Biology Center, Czech Academy of Sciences, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Mathieu Gissot
- University of 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.
| |
Collapse
|
25
|
Hamilton WL, Claessens A, Otto TD, Kekre M, Fairhurst RM, Rayner JC, Kwiatkowski D. Extreme mutation bias and high AT content in Plasmodium falciparum. Nucleic Acids Res 2017; 45:1889-1901. [PMID: 27994033 PMCID: PMC5389722 DOI: 10.1093/nar/gkw1259] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/01/2016] [Indexed: 01/31/2023] Open
Abstract
For reasons that remain unknown, the Plasmodium falciparum genome has an exceptionally high AT content compared to other Plasmodium species and eukaryotes in general - nearly 80% in coding regions and approaching 90% in non-coding regions. Here, we examine how this phenomenon relates to genome-wide patterns of de novo mutation. Mutation accumulation experiments were performed by sequential cloning of six P. falciparum isolates growing in human erythrocytes in vitro for 4 years, with 279 clones sampled for whole genome sequencing at different time points. Genome sequence analysis of these samples revealed a significant excess of G:C to A:T transitions compared to other types of nucleotide substitution, which would naturally cause AT content to equilibrate close to the level seen across the P. falciparum reference genome (80.6% AT). These data also uncover an extremely high rate of small indel mutation relative to other species, primarily associated with repetitive AT-rich sequences, in addition to larger-scale structural rearrangements focused in antigen-coding var genes. In conclusion, high AT content in P. falciparum is driven by a systematic mutational bias and ultimately leads to an unusual level of microstructural plasticity, raising the question of whether this contributes to adaptive evolution.
Collapse
Affiliation(s)
- William L Hamilton
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK.,University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0SP, UK
| | - Antoine Claessens
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK.,Medical Research Council Unit The Gambia, Atlantic Road, Fajara, P.O. Box 273, Banjul, The Gambia.,Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Thomas D Otto
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK
| | - Mihir Kekre
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK
| | - Dominic Kwiatkowski
- Malaria Programme, Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK.,Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| |
Collapse
|
26
|
Ubhe S, Rawat M, Verma S, Anamika K, Karmodiya K. Genome-wide identification of novel intergenic enhancer-like elements: implications in the regulation of transcription in Plasmodium falciparum. BMC Genomics 2017; 18:656. [PMID: 28836940 PMCID: PMC5569477 DOI: 10.1186/s12864-017-4052-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 08/11/2017] [Indexed: 01/28/2023] Open
Abstract
Background The molecular mechanisms of transcriptional regulation are poorly understood in Plasmodium falciparum. In addition, most of the genes in Plasmodium falciparum are transcriptionally poised and only a handful of cis-regulatory elements are known to operate in transcriptional regulation. Here, we employed an epigenetic signature based approach to identify significance of previously uncharacterised intergenic regions enriched with histone modification marks leading to discovery of enhancer-like elements. Results We found that enhancer-like elements are significantly enriched with H3K4me1, generate unique non-coding bi-directional RNAs and majority of them can function as cis-regulators. Furthermore, functional enhancer reporter assay demonstrates that the enhancer-like elements regulate transcription of target genes in Plasmodium falciparum. Our study also suggests that the Plasmodium genome segregates functionally related genes into discrete housekeeping and pathogenicity/virulence clusters, presumably for robust transcriptional control of virulence/pathogenicity genes. Conclusions This report contributes to the understanding of parasite regulatory genomics by identification of enhancer-like elements, defining their epigenetic and transcriptional features and provides a resource of functional cis-regulatory elements that may give insights into the virulence/pathogenicity of Plasmodium falciparum. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-4052-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Suyog Ubhe
- Department of Biology, Indian Institute of Science Education and Research, Pashan, Pune, 411008, India
| | - Mukul Rawat
- Department of Biology, Indian Institute of Science Education and Research, Pashan, Pune, 411008, India
| | - Srikant Verma
- Labs, Persistent Systems Limited, Pingala - Aryabhata, Erandwane, Pune, 411004, India
| | - Krishanpal Anamika
- Labs, Persistent Systems Limited, Pingala - Aryabhata, Erandwane, Pune, 411004, India
| | - Krishanpal Karmodiya
- Department of Biology, Indian Institute of Science Education and Research, Pashan, Pune, 411008, India.
| |
Collapse
|
27
|
Santos JM, Josling G, Ross P, Joshi P, Orchard L, Campbell T, Schieler A, Cristea IM, Llinás M. Red Blood Cell Invasion by the Malaria Parasite Is Coordinated by the PfAP2-I Transcription Factor. Cell Host Microbe 2017; 21:731-741.e10. [PMID: 28618269 PMCID: PMC5855115 DOI: 10.1016/j.chom.2017.05.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 02/16/2017] [Accepted: 05/23/2017] [Indexed: 10/19/2022]
Abstract
Obligate intracellular parasites must efficiently invade host cells in order to mature and be transmitted. For the malaria parasite Plasmodium falciparum, invasion of host red blood cells (RBCs) is essential. Here we describe a parasite-specific transcription factor PfAP2-I, belonging to the Apicomplexan AP2 (ApiAP2) family, that is responsible for regulating the expression of genes involved in RBC invasion. Our genome-wide analysis by ChIP-seq shows that PfAP2-I interacts with a specific DNA motif in the promoters of target genes. Although PfAP2-I contains three AP2 DNA-binding domains, only one is required for binding of the target genes during blood stage development. Furthermore, we find that PfAP2-I associates with several chromatin-associated proteins, including the Plasmodium bromodomain protein PfBDP1 and that complex formation is associated with transcriptional regulation. As a key regulator of red blood cell invasion, PfAP2-I represents a potential new antimalarial therapeutic target.
Collapse
Affiliation(s)
- Joana Mendonca Santos
- Department of Biochemistry and Molecular Biology and Huck Center for Malaria Research, Pennsylvania State University, State College, PA 16802, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Gabrielle Josling
- Department of Biochemistry and Molecular Biology and Huck Center for Malaria Research, Pennsylvania State University, State College, PA 16802, USA
| | - Philipp Ross
- Department of Biochemistry and Molecular Biology and Huck Center for Malaria Research, Pennsylvania State University, State College, PA 16802, USA
| | - Preeti Joshi
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Lindsey Orchard
- Department of Biochemistry and Molecular Biology and Huck Center for Malaria Research, Pennsylvania State University, State College, PA 16802, USA
| | - Tracey Campbell
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Ariel Schieler
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Ileana M Cristea
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology and Huck Center for Malaria Research, Pennsylvania State University, State College, PA 16802, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA; Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Chemistry and Huck Center for Infectious Disease Dynamics, Pennsylvania State University, State College, PA 16802, USA.
| |
Collapse
|
28
|
Gupta AP, Bozdech Z. Epigenetic landscapes underlining global patterns of gene expression in the human malaria parasite, Plasmodium falciparum. Int J Parasitol 2017; 47:399-407. [PMID: 28414071 DOI: 10.1016/j.ijpara.2016.10.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/15/2016] [Accepted: 10/20/2016] [Indexed: 12/31/2022]
Abstract
The dynamic chromatin landscape displaying combinatorial complexity of the epigenome impacts gene expression that underlies many events of differentiation and cell cycle progression. In the past few years, epigenetic mechanisms have emerged as important processes involved in the tight gene regulation in malaria parasites, Plasmodium spp. Focusing predominantly on Plasmodium falciparum, the species associated with the most severe form of the disease, many advances have been made in our understanding of the interaction between transcriptional regulation and epigenetic mechanisms as the pivotal processes in regulating life cycle progression, host parasite interactions and parasite adaptation to the host environment. This review focuses on the epigenome and its effect on transcriptional regulation in P. falciparum, highlighting its unique, evolutionary diverse features.
Collapse
Affiliation(s)
- Archana P Gupta
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
| |
Collapse
|
29
|
Quantitative chromatin proteomics reveals a dynamic histone post-translational modification landscape that defines asexual and sexual Plasmodium falciparum parasites. Sci Rep 2017; 7:607. [PMID: 28377601 PMCID: PMC5428830 DOI: 10.1038/s41598-017-00687-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 03/08/2017] [Indexed: 01/24/2023] Open
Abstract
Gene expression in Plasmodia integrates post-transcriptional regulation with epigenetic marking of active genomic regions through histone post-translational modifications (PTMs). To generate insights into the importance of histone PTMs to the entire asexual and sexual developmental cycles of the parasite, we used complementary and comparative quantitative chromatin proteomics to identify and functionally characterise histone PTMs in 8 distinct life cycle stages of P. falciparum parasites. ~500 individual histone PTMs were identified of which 106 could be stringently validated. 46 individual histone PTMs and 30 co-existing PTMs were fully quantified with high confidence. Importantly, 15 of these histone PTMs are novel for Plasmodia (e.g. H3K122ac, H3K27me3, H3K56me3). The comparative nature of the data revealed a highly dynamic histone PTM landscape during life cycle development, with a set of histone PTMs (H3K4ac, H3K9me1 and H3K36me2) displaying a unique and conserved abundance profile exclusively during gametocytogenesis (P < 0.001). Euchromatic histone PTMs are abundant during schizogony and late gametocytes; heterochromatic PTMs mark early gametocytes. Collectively, this data provides the most accurate, complete and comparative chromatin proteomic analyses of the entire life cycle development of malaria parasites. A substantial association between histone PTMs and stage-specific transition provides insights into the intricacies characterising Plasmodial developmental biology.
Collapse
|
30
|
Arnot DE, Jensen ATR. Antigenic Variation and the Genetics and Epigenetics of the PfEMP1 Erythrocyte Surface Antigens in Plasmodium falciparum Malaria. ADVANCES IN APPLIED MICROBIOLOGY 2016; 74:77-96. [PMID: 21459194 DOI: 10.1016/b978-0-12-387022-3.00007-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
How immunity to malaria develops remains one of the great unresolved issues in bio-medicine and resolution of its various paradoxes is likely to be the key to developing effective malaria vaccines. The basic epidemiological observations are; under conditions of intense natural transmission, humans do become immune to P. falciparum malaria, but this is a slow process requiring multiple disease episodes which many, particularly young children, do not survive. Adult survivors are immune to the symptoms of malaria, and unless pregnant, can control the growth of most or all new inoculations. Sterile immunity is not achieved and chronic parasitization of apparently healthy adults is the norm. In this article, we analyse the best understood malaria "antigenic variation" system, that based on Plasmodium falciparum's PfEMP1-type cytoadhesion antigens, and critically review recent literature on the function and control of this multi-gene family of parasite variable surface antigens.
Collapse
Affiliation(s)
- David E Arnot
- Centre for Medical Parasitology, Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, CSS Oester Farimagsgade 5, Copenhagen K, Denmark; Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), CSS Oester Farimagsgade 5, Copenhagen K, Denmark; Institute of Immunology and Infection Research, School of Biology, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | | |
Collapse
|
31
|
Adjalley SH, Chabbert CD, Klaus B, Pelechano V, Steinmetz LM. Landscape and Dynamics of Transcription Initiation in the Malaria Parasite Plasmodium falciparum. Cell Rep 2016; 14:2463-75. [PMID: 26947071 DOI: 10.1016/j.celrep.2016.02.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 12/09/2015] [Accepted: 02/01/2016] [Indexed: 12/20/2022] Open
Abstract
A comprehensive map of transcription start sites (TSSs) across the highly AT-rich genome of P. falciparum would aid progress toward deciphering the molecular mechanisms that underlie the timely regulation of gene expression in this malaria parasite. Using high-throughput sequencing technologies, we generated a comprehensive atlas of transcription initiation events at single-nucleotide resolution during the parasite intra-erythrocytic developmental cycle. This detailed analysis of TSS usage enabled us to define architectural features of plasmodial promoters. We demonstrate that TSS selection and strength are constrained by local nucleotide composition. Furthermore, we provide evidence for coordinate and stage-specific TSS usage from distinct sites within the same transcription unit, thereby producing transcript isoforms, a subset of which are developmentally regulated. This work offers a framework for further investigations into the interactions between genomic sequences and regulatory factors governing the complex transcriptional program of this major human pathogen.
Collapse
Affiliation(s)
- Sophie H Adjalley
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Christophe D Chabbert
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Bernd Klaus
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Vicent Pelechano
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Lars M Steinmetz
- Genome Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany; Stanford Genome Technology Center, Palo Alto, CA 94304, USA; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
| |
Collapse
|
32
|
Zhu L, Mok S, Imwong M, Jaidee A, Russell B, Nosten F, Day NP, White NJ, Preiser PR, Bozdech Z. New insights into the Plasmodium vivax transcriptome using RNA-Seq. Sci Rep 2016; 6:20498. [PMID: 26858037 PMCID: PMC4746618 DOI: 10.1038/srep20498] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 01/05/2016] [Indexed: 12/13/2022] Open
Abstract
Historically seen as a benign disease, it is now becoming clear that Plasmodium vivax can cause significant morbidity. Effective control strategies targeting P. vivax malaria is hindered by our limited understanding of vivax biology. Here we established the P. vivax transcriptome of the Intraerythrocytic Developmental Cycle (IDC) of two clinical isolates in high resolution by Illumina HiSeq platform. The detailed map of transcriptome generates new insights into regulatory mechanisms of individual genes and reveals their intimate relationship with specific biological functions. A transcriptional hotspot of vir genes observed on chromosome 2 suggests a potential active site modulating immune evasion of the Plasmodium parasite across patients. Compared to other eukaryotes, P. vivax genes tend to have unusually long 5′ untranslated regions and also present multiple transcription start sites. In contrast, alternative splicing is rare in P. vivax but its association with the late schizont stage suggests some of its significance for gene function. The newly identified transcripts, including up to 179 vir like genes and 3018 noncoding RNAs suggest an important role of these gene/transcript classes in strain specific transcriptional regulation.
Collapse
Affiliation(s)
- Lei Zhu
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Sachel Mok
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Mallika Imwong
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Anchalee Jaidee
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Bruce Russell
- Yong Loo Lin School of Medicine, National University Singapore, Singapore
| | - Francois Nosten
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.,Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand
| | - Nicholas P Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Peter R Preiser
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, Singapore
| |
Collapse
|
33
|
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.
Collapse
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.
| |
Collapse
|
34
|
Ay F, Bunnik EM, Varoquaux N, Vert JP, Noble WS, Le Roch KG. Multiple dimensions of epigenetic gene regulation in the malaria parasite Plasmodium falciparum: gene regulation via histone modifications, nucleosome positioning and nuclear architecture in P. falciparum. Bioessays 2014; 37:182-94. [PMID: 25394267 DOI: 10.1002/bies.201400145] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Plasmodium falciparum is the most deadly human malarial parasite, responsible for an estimated 207 million cases of disease and 627,000 deaths in 2012. Recent studies reveal that the parasite actively regulates a large fraction of its genes throughout its replicative cycle inside human red blood cells and that epigenetics plays an important role in this precise gene regulation. Here, we discuss recent advances in our understanding of three aspects of epigenetic regulation in P. falciparum: changes in histone modifications, nucleosome occupancy and the three-dimensional genome structure. We compare these three aspects of the P. falciparum epigenome to those of other eukaryotes, and show that large-scale compartmentalization is particularly important in determining histone decomposition and gene regulation in P. falciparum. We conclude by presenting a gene regulation model for P. falciparum that combines the described epigenetic factors, and by discussing the implications of this model for the future of malaria research.
Collapse
Affiliation(s)
- Ferhat Ay
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | | | | | | | | | | |
Collapse
|
35
|
Russell K, Cheng CH, Bizzaro JW, Ponts N, Emes RD, Le Roch K, Marx KA, Horrocks P. Homopolymer tract organization in the human malarial parasite Plasmodium falciparum and related Apicomplexan parasites. BMC Genomics 2014; 15:848. [PMID: 25281558 PMCID: PMC4194402 DOI: 10.1186/1471-2164-15-848] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 09/24/2014] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Homopolymeric tracts, particularly poly dA.dT, are enriched within the intergenic sequences of eukaryotic genomes where they appear to act as intrinsic regulators of nucleosome positioning. A previous study of the incomplete genome of the human malarial parasite Plasmodium falciparum reports a higher than expected enrichment of poly dA.dT tracts, far above that anticipated even in this highly AT rich genome. Here we report an analysis of the relative frequency, length and spatial arrangement of homopolymer tracts for the complete P. falciparum genome, extending this analysis to twelve additional genomes of Apicomplexan parasites important to human and animal health. In addition, using nucleosome-positioning data available for P. falciparum, we explore the correlation of poly dA.dT tracts with nucleosome-positioning data over key expression landmarks within intergenic regions. RESULTS We describe three apparent lineage-specific patterns of homopolymeric tract organization within the intergenic regions of these Apicomplexan parasites. Moreover, a striking pattern of enrichment of overly long poly dA.dT tracts in the intergenic regions of Plasmodium spp. uniquely extends into protein coding sequences. There is a conserved spatial arrangement of poly dA.dT immediately flanking open reading frames and over predicted core promoter sites. These key landmarks are all relatively depleted in nucleosomes in P. falciparum, as would be expected for poly dA.dT acting as nucleosome exclusion sequences. CONCLUSIONS Previous comparative studies of homopolymer tract organization emphasize evolutionary diversity; this is the first report of such an analysis within a single phylum. Our data provide insights into the evolution of homopolymeric tracts and the selective pressures at play in their maintenance and expansion.
Collapse
Affiliation(s)
- Karen Russell
- />Institute for Science and Technology in Medicine, Keele University, Stoke-on-Trent, ST5 5BG Staffordshire, UK
| | - Chia-Ho Cheng
- />Center for Intelligent Biomaterials, University of Massachusetts Lowell, Lowell, MA 01854 USA
- />Hebrew SeniorLife, Institute for Aging Research, Boston, MA 02131 USA
| | | | - Nadia Ponts
- />National Institute for Agricultural Research (INRA), UR1264-Mycology and Food Safety (MycSA), CS20032, 33882 Villenave d’Ornon Cedex, France
| | - Richard D Emes
- />School of Veterinary Medicine and Science, University of Nottingham, LE12 5RD Nottingham, Leicestershire, UK
- />Advanced Data Analysis Centre, University of Nottingham, Nottingham, UK
| | - Karine Le Roch
- />Department Cell Biology and Neuroscience, University of California, Riverside, CA 92521 USA
| | - Kenneth A Marx
- />Center for Intelligent Biomaterials, University of Massachusetts Lowell, Lowell, MA 01854 USA
| | - Paul Horrocks
- />Institute for Science and Technology in Medicine, Keele University, Stoke-on-Trent, ST5 5BG Staffordshire, UK
| |
Collapse
|
36
|
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.
Collapse
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
| |
Collapse
|
37
|
Ghouila A, Florent I, Guerfali FZ, Terrapon N, Laouini D, Yahia SB, Gascuel O, Bréhélin L. Identification of divergent protein domains by combining HMM-HMM comparisons and co-occurrence detection. PLoS One 2014; 9:e95275. [PMID: 24901648 PMCID: PMC4046975 DOI: 10.1371/journal.pone.0095275] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 03/26/2014] [Indexed: 01/03/2023] Open
Abstract
Identification of protein domains is a key step for understanding protein function. Hidden Markov Models (HMMs) have proved to be a powerful tool for this task. The Pfam database notably provides a large collection of HMMs which are widely used for the annotation of proteins in sequenced organisms. This is done via sequence/HMM comparisons. However, this approach may lack sensitivity when searching for domains in divergent species. Recently, methods for HMM/HMM comparisons have been proposed and proved to be more sensitive than sequence/HMM approaches in certain cases. However, these approaches are usually not used for protein domain discovery at a genome scale, and the benefit that could be expected from their utilization for this problem has not been investigated. Using proteins of P. falciparum and L. major as examples, we investigate the extent to which HMM/HMM comparisons can identify new domain occurrences not already identified by sequence/HMM approaches. We show that although HMM/HMM comparisons are much more sensitive than sequence/HMM comparisons, they are not sufficiently accurate to be used as a standalone complement of sequence/HMM approaches at the genome scale. Hence, we propose to use domain co-occurrence — the general domain tendency to preferentially appear along with some favorite domains in the proteins — to improve the accuracy of the approach. We show that the combination of HMM/HMM comparisons and co-occurrence domain detection boosts protein annotations. At an estimated False Discovery Rate of 5%, it revealed 901 and 1098 new domains in Plasmodium and Leishmania proteins, respectively. Manual inspection of part of these predictions shows that it contains several domain families that were missing in the two organisms. All new domain occurrences have been integrated in the EuPathDomains database, along with the GO annotations that can be deduced.
Collapse
Affiliation(s)
- Amel Ghouila
- Institut de Biologie Computationnelle, LIRMM, CNRS, Univ. Montpellier 2, Montpellier, France
- Computer Science Department, Faculty of Sciences of Tunis, Tunis, Tunisia
| | - Isabelle Florent
- Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle, UMR7245 CNRS-MNHN, Molécules de Communication et Adaptation des Micro-organismes, Adaptation des Protozoaires à leur Environnent, Paris, France
| | - Fatma Zahra Guerfali
- Institut Pasteur de Tunis, LR11IPT02, Laboratory of Transmission, Control and Immunobiology of Infections (LTCII), Tunis-Belvédère, Tunisia
- Université Tunis El Manar, Tunis, Tunisia
| | - Nicolas Terrapon
- Centre National de la Recherche Scientifique, Aix-Marseille Université, CNRS UMR 7257, AFMB, Marseille, France
| | - Dhafer Laouini
- Institut Pasteur de Tunis, LR11IPT02, Laboratory of Transmission, Control and Immunobiology of Infections (LTCII), Tunis-Belvédère, Tunisia
- Université Tunis El Manar, Tunis, Tunisia
| | - Sadok Ben Yahia
- Computer Science Department, Faculty of Sciences of Tunis, Tunis, Tunisia
| | - Olivier Gascuel
- Institut de Biologie Computationnelle, LIRMM, CNRS, Univ. Montpellier 2, Montpellier, France
| | - Laurent Bréhélin
- Institut de Biologie Computationnelle, LIRMM, CNRS, Univ. Montpellier 2, Montpellier, France
- * E-mail:
| |
Collapse
|
38
|
Hansen FK, Sumanadasa SDM, Stenzel K, Duffy S, Meister S, Marek L, Schmetter R, Kuna K, Hamacher A, Mordmüller B, Kassack MU, Winzeler EA, Avery VM, Andrews KT, Kurz T. Discovery of HDAC inhibitors with potent activity against multiple malaria parasite life cycle stages. Eur J Med Chem 2014; 82:204-13. [PMID: 24904967 DOI: 10.1016/j.ejmech.2014.05.050] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 05/12/2014] [Accepted: 05/21/2014] [Indexed: 10/25/2022]
Abstract
In this work we investigated the antiplasmodial activity of a series of HDAC inhibitors containing an alkoxyamide connecting-unit linker region. HDAC inhibitor 1a (LMK235), previously shown to be a novel and specific inhibitor of human HDAC4 and 5, was used as a starting point to rapidly construct a mini-library of HDAC inhibitors using a straightforward solid-phase supported synthesis. Several of these novel HDAC inhibitors were found to have potent in vitro activity against asexual stage Plasmodium falciparum malaria parasites. Representative compounds were shown to hyperacetylate P. falciparum histones and to inhibit deacetylase activity of recombinant PfHDAC1 and P. falciparum nuclear extracts. All compounds were also screened in vitro for activity against Plasmodium berghei exo-erythrocytic stages and selected compounds were further tested against late stage (IV and V) P. falciparum gametocytes. Of note, some compounds showed nanomolar activity against all three life cycle stages tested (asexual, exo-erythrocytic and gametocyte stages) and several compounds displayed significantly increased parasite selectivity compared to the reference HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). These data suggest that it may be possible to develop HDAC inhibitors that target multiple malaria parasite life cycle stages.
Collapse
Affiliation(s)
- Finn K Hansen
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Subathdrage D M Sumanadasa
- Eskitis Institute for Drug Discovery, Don Young Road, Nathan Campus, Griffith University, QLD 4111, Australia
| | - Katharina Stenzel
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Sandra Duffy
- Eskitis Institute for Drug Discovery, Don Young Road, Nathan Campus, Griffith University, QLD 4111, Australia
| | - Stephan Meister
- Department of Pediatrics, University of California, San Diego, School of Medicine, 9500 Gilman Drive 0741, La Jolla, CA 92093, USA
| | - Linda Marek
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Rebekka Schmetter
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Krystina Kuna
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Alexandra Hamacher
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Benjamin Mordmüller
- Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Wilhelmstr. 27, 72074 Tübingen, Germany; Medical Research Laboratory, Albert Schweitzer Hospital, Lambaréné, Gabon
| | - Matthias U Kassack
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Elizabeth A Winzeler
- Department of Pediatrics, University of California, San Diego, School of Medicine, 9500 Gilman Drive 0741, La Jolla, CA 92093, USA
| | - Vicky M Avery
- Eskitis Institute for Drug Discovery, Don Young Road, Nathan Campus, Griffith University, QLD 4111, Australia
| | - Katherine T Andrews
- Eskitis Institute for Drug Discovery, Don Young Road, Nathan Campus, Griffith University, QLD 4111, Australia.
| | - Thomas Kurz
- Institut für Pharmazeutische und Medizinische Chemie, Heinrich Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
| |
Collapse
|
39
|
Hansen FK, Skinner-Adams TS, Duffy S, Marek L, Sumanadasa SDM, Kuna K, Held J, Avery VM, Andrews KT, Kurz T. Synthesis, antimalarial properties, and SAR studies of alkoxyurea-based HDAC inhibitors. ChemMedChem 2014; 9:665-70. [PMID: 24497437 DOI: 10.1002/cmdc.201300469] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/06/2014] [Indexed: 11/06/2022]
Abstract
Histone deacetylase (HDAC) inhibitors are an emerging class of potential antimalarial drugs. We investigated the antiplasmodial properties of 16 alkoxyurea-based HDAC inhibitors containing various cap and zinc binding groups (ZBGs). Ten compounds displayed sub-micromolar activity against the 3D7 line of Plasmodium falciparum. Structure-activity relationship studies revealed that a hydroxamic acid ZBG is crucial for antiplasmodial activity, and that the introduction of bulky alkyl substituents to cap groups increases potency against asexual blood-stage parasites. We also demonstrate that selected compounds cause hyperacetylation of P. falciparum histone H4, indicating inhibition of one or more PfHDACs. To assess the selectivity of alkoxyurea-based HDAC inhibitors for parasite over normal mammalian cells, the cytotoxicity of representative compounds was evaluated against neonatal foreskin fibroblast (NFF) cells. The most active compound, 6-((3-(4-(tert-butyl)phenyl)ureido)oxy)-N-hydroxyhexanamide (1 e, Pf3D7 IC50 : 0.16 μM) was 31-fold more toxic against the asexual blood stages than towards normal mammalian cells. Moreover, a subset of four structurally diverse HDAC inhibitors revealed moderate activity against late-stage (IV-V) gametocytes.
Collapse
Affiliation(s)
- Finn K Hansen
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf (Germany)
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Miao J, Lawrence M, Jeffers V, Zhao F, Parker D, Ge Y, Sullivan WJ, Cui L. Extensive lysine acetylation occurs in evolutionarily conserved metabolic pathways and parasite-specific functions during Plasmodium falciparum intraerythrocytic development. Mol Microbiol 2013; 89:660-75. [PMID: 23796209 DOI: 10.1111/mmi.12303] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2013] [Indexed: 12/31/2022]
Abstract
Lysine acetylation has emerged as a major post-translational modification involved in diverse cellular functions. Using a combination of immunoisolation and liquid chromatography coupled to accurate mass spectrometry, we determined the first acetylome of the human malaria parasite Plasmodium falciparum during its active proliferation in erythrocytes with 421 acetylation sites identified in 230 proteins. Lysine-acetylated proteins are distributed in the nucleus, cytoplasm, mitochondrion and apicoplast. Whereas occurrence of lysine acetylation in a similarly wide range of cellular functions suggests conservation of lysine acetylation through evolution, the Plasmodium acetylome also revealed significant divergence from those of other eukaryotes and even the closely related parasite Toxoplasma. This divergence is reflected in the acetylation of a large number of Plasmodium-specific proteins and different acetylation sites in evolutionarily conserved acetylated proteins. A prominent example is the abundant acetylation of proteins in the glycolysis pathway but relatively deficient acetylation of enzymes in the citrate cycle. Using specific transgenic lines and inhibitors, we determined that the acetyltransferase PfMYST and lysine deacetylases play important roles in regulating the dynamics of cytoplasmic protein acetylation. The Plasmodium acetylome provides an exciting start point for further exploration of functions of acetylation in the biology of malaria parasites.
Collapse
Affiliation(s)
- Jun Miao
- Department of Entomology, Pennsylvania State University, 501 ASI Building, University Park, PA 16802, USA
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Hasenkamp S, Russell K, Ullah I, Horrocks P. Functional analysis of the 5' untranslated region of the phosphoglutamase 2 transcript in Plasmodium falciparum. Acta Trop 2013; 127:69-74. [PMID: 23567550 DOI: 10.1016/j.actatropica.2013.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 03/18/2013] [Accepted: 03/20/2013] [Indexed: 01/07/2023]
Abstract
Plasmodium falciparum transcripts contain long untranslated regions (UTR), with some of the longest in any eukaryote that uses monocistronic transcription. Owing to the extreme AT nucleotide bias within the intergenic regions that encode these UTR, attempts to characterise how they are apportioned over genes and to describe their contribution to the absolute and temporal control of gene expression have been limited. Here we describe a study using a typical house-keeping gene that encodes phosphoglutamase 2 (PFD0660w), whose expression is subject to developmentally linked control during intraerythrocytic development. We show that deletion of a significant proportion (80%) of the predicted 5' UTR has no apparent effect on the developmentally linked expression of a luciferase reporter cassette. Further, serial deletions reveal that whilst the absolute level of transcription is unaffected when up to 50% of the predicted 5' UTR is removed, the subsequent efficiency of translation is affected. These data provide key insights into the interplay of transcriptional and post-transcriptional mechanisms in the control of gene expression in this important human pathogen.
Collapse
Affiliation(s)
- Sandra Hasenkamp
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, United Kingdom
| | | | | | | |
Collapse
|
42
|
Russell K, Hasenkamp S, Emes R, Horrocks P. Analysis of the spatial and temporal arrangement of transcripts over intergenic regions in the human malarial parasite Plasmodium falciparum. BMC Genomics 2013; 14:267. [PMID: 23601558 PMCID: PMC3681616 DOI: 10.1186/1471-2164-14-267] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 04/06/2013] [Indexed: 11/25/2022] Open
Abstract
Background The ability of the human malarial parasite Plasmodium falciparum to invade, colonise and multiply within diverse host environments, as well as to manifest its virulence within the human host, are activities tightly linked to the temporal and spatial control of gene expression. Yet, despite the wealth of high throughput transcriptomic data available for this organism there is very little information regarding the location of key transcriptional landmarks or their associated cis-acting regulatory elements. Here we provide a systematic exploration of the size and organisation of transcripts within intergenic regions to yield surrogate information regarding transcriptional landmarks, and to also explore the spatial and temporal organisation of transcripts over these poorly characterised genomic regions. Results Utilising the transcript data for a cohort of 105 genes we demonstrate that the untranscribed regions of mRNA are large and apportioned predominantly to the 5′ end of the open reading frame. Given the relatively compact size of the P. falciparum genome, we suggest that whilst transcriptional units are likely to spatially overlap, temporal co-transcription of adjacent transcriptional units is actually limited. Critically, the size of intergenic regions is directly dependent on the orientation of the two transcriptional units arrayed over them, an observation we extend to an analysis of the complete sequences of twelve additional organisms that share moderately compact genomes. Conclusions Our study provides a theoretical framework that extends our current understanding of the transcriptional landscape across the P. falciparum genome. Demonstration of a consensus gene-spacing rule that is shared between P. falciparum and ten other moderately compact genomes of apicomplexan parasites reveals the potential for our findings to have a wider impact across a phylum that contains many organisms important to human and veterinary health.
Collapse
Affiliation(s)
- Karen Russell
- Institute for Science and Technology in Medicine, Keele University, Huxley Building, Staffordshire ST5 5BG, United Kingdom
| | | | | | | |
Collapse
|
43
|
Hoeijmakers WAM, Salcedo-Amaya AM, Smits AH, Françoijs KJ, Treeck M, Gilberger TW, Stunnenberg HG, Bártfai R. H2A.Z/H2B.Z double-variant nucleosomes inhabit the AT-rich promoter regions of the Plasmodium falciparum genome. Mol Microbiol 2013; 87:1061-73. [PMID: 23320541 PMCID: PMC3594968 DOI: 10.1111/mmi.12151] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2013] [Indexed: 02/06/2023]
Abstract
Histone variants are key components of the epigenetic code and evolved to perform specific functions in transcriptional regulation, DNA repair, chromosome segregation and other fundamental processes. Although variants for histone H2A and H3 are found throughout the eukaryotic kingdom, variants of histone H2B and H4 are rarely encountered. H2B.Z is one of those rare H2B variants and is apicomplexan-specific. Here we show that in Plasmodium falciparum H2B.Z localizes to euchromatic intergenic regions throughout intraerythrocytic development and together with H2A.Z forms a double-variant nucleosome subtype. These nucleosomes are enriched in promoters over 3′ intergenic regions and their occupancy generally correlates with the strength of the promoter, but not with its temporal activity. Remarkably, H2B.Z occupancy levels exhibit a clear correlation with the base-composition of the underlying DNA, raising the intriguing possibility that the extreme AT content of the intergenic regions within the Plasmodium genome might be instructive for histone variant deposition. In summary, our data show that the H2A.Z/H2B.Z double-variant nucleosome demarcates putative regulatory regions of the P. falciparum epigenome and likely provides a scaffold for dynamic regulation of gene expression in this deadly human pathogen.
Collapse
Affiliation(s)
- Wieteke A M Hoeijmakers
- Department of Molecular Biology, Radboud University, Nijmegen Centre for Molecular Life Sciences, Nijmegen 6525GA, the Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Deshmukh AS, Srivastava S, Dhar SK. Plasmodium falciparum: epigenetic control of var gene regulation and disease. Subcell Biochem 2013; 61:659-682. [PMID: 23150271 DOI: 10.1007/978-94-007-4525-4_28] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Plasmodium falciparum, one of the deadliest parasites on earth causes human malaria resulting one million deaths annually. Central to the parasite pathogenicity and morbidity is the switching of parasite virulence (var) gene expression causing host immune evasion. The regulation of Plasmodium var gene expression is poorly understood. The complex life cycle of Plasmodium and mutually exclusive expression pattern of var genes make this disease difficult to control. Recent studies have demonstrated the pivotal role of epigenetic mechanism for control of coordinated expression of var genes, important for various clinical manifestations of malaria. In this review, we discuss about different Plasmodium histones and their various modifications important for gene expression and gene repression.Contribution of epigenetic mechanism to understand the var gene expression is also highlighted. We also describe in details P. falciparum nuclear architecture including heterochromatin, euchromatin and telomeric regions and their importance in subtelomeric and centrally located var gene expression. Finally, we explore the possibility of using Histone Acetyl Transferase (HAT) and Histone Deacetylase (HDAC)inhibitors against multi-drug resistance malaria parasites to provide another line of treatment for malaria.
Collapse
Affiliation(s)
- Abhijit S Deshmukh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India
| | | | | |
Collapse
|
45
|
Cortés A, Crowley VM, Vaquero A, Voss TS. A view on the role of epigenetics in the biology of malaria parasites. PLoS Pathog 2012; 8:e1002943. [PMID: 23271963 PMCID: PMC3521673 DOI: 10.1371/journal.ppat.1002943] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Alfred Cortés
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Catalonia, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Catalonia, Spain
- * E-mail:
| | - Valerie M. Crowley
- Institute for Research in Biomedicine (IRB), Barcelona, Catalonia, Spain
| | - Alejandro Vaquero
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
| | - Till S. Voss
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| |
Collapse
|
46
|
Lajoie M, Gascuel O, Lefort V, Bréhélin L. Computational discovery of regulatory elements in a continuous expression space. Genome Biol 2012. [PMID: 23186104 PMCID: PMC4053739 DOI: 10.1186/gb-2012-13-11-r109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Approaches for regulatory element discovery from gene expression data usually rely on clustering algorithms to partition the data into clusters of co-expressed genes. Gene regulatory sequences are then mined to find overrepresented motifs in each cluster. However, this ad hoc partition rarely fits the biological reality. We propose a novel method called RED2 that avoids data clustering by estimating motif densities locally around each gene. We show that RED2 detects numerous motifs not detected by clustering-based approaches, and that most of these correspond to characterized motifs. RED2 can be accessed online through a user-friendly interface.
Collapse
|
47
|
Oehring SC, Woodcroft BJ, Moes S, Wetzel J, Dietz O, Pulfer A, Dekiwadia C, Maeser P, Flueck C, Witmer K, Brancucci NMB, Niederwieser I, Jenoe P, Ralph SA, Voss TS. Organellar proteomics reveals hundreds of novel nuclear proteins in the malaria parasite Plasmodium falciparum. Genome Biol 2012. [PMID: 23181666 PMCID: PMC4053738 DOI: 10.1186/gb-2012-13-11-r108] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The post-genomic era of malaria research provided unprecedented insights into the biology of Plasmodium parasites. Due to the large evolutionary distance to model eukaryotes, however, we lack a profound understanding of many processes in Plasmodium biology. One example is the cell nucleus, which controls the parasite genome in a development- and cell cycle-specific manner through mostly unknown mechanisms. To study this important organelle in detail, we conducted an integrative analysis of the P. falciparum nuclear proteome. RESULTS We combined high accuracy mass spectrometry and bioinformatic approaches to present for the first time an experimentally determined core nuclear proteome for P. falciparum. Besides a large number of factors implicated in known nuclear processes, one-third of all detected proteins carry no functional annotation, including many phylum- or genus-specific factors. Importantly, extensive experimental validation using 30 transgenic cell lines confirmed the high specificity of this inventory, and revealed distinct nuclear localization patterns of hitherto uncharacterized proteins. Further, our detailed analysis identified novel protein domains potentially implicated in gene transcription pathways, and sheds important new light on nuclear compartments and processes including regulatory complexes, the nucleolus, nuclear pores, and nuclear import pathways. CONCLUSION Our study provides comprehensive new insight into the biology of the Plasmodium nucleus and will serve as an important platform for dissecting general and parasite-specific nuclear processes in malaria parasites. Moreover, as the first nuclear proteome characterized in any protist organism, it will provide an important resource for studying evolutionary aspects of nuclear biology.
Collapse
|
48
|
Ecker A, Lewis RE, Ekland EH, Jayabalasingham B, Fidock DA. Tricks in Plasmodium's molecular repertoire--escaping 3'UTR excision-based conditional silencing of the chloroquine resistance transporter gene. Int J Parasitol 2012; 42:969-74. [PMID: 23023047 DOI: 10.1016/j.ijpara.2012.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2012] [Revised: 08/18/2012] [Accepted: 09/17/2012] [Indexed: 11/25/2022]
Abstract
In the human malaria parasite Plasmodium falciparum, the major determinant of chloroquine resistance, P. falciparum chloroquine resistance transporter (pfcrt), likely plays an essential role in asexual blood stages, thus precluding conventional gene targeting approaches. We attempted to conditionally silence the expression of its ortholog in Plasmodium berghei (pbcrt) through Flp recombinase-mediated excision of the 3'untranslated region (UTR) during mosquito passage. However, parasites maintained pbcrt expression despite 3'UTR excision. Characterisation of these pbcrt mRNAs, by 3'rapid amplification of cDNA ends, identified several replacement 3'UTR sequences. Our observations demonstrate the astounding genetic plasticity of this parasite when faced with the loss of an essential gene.
Collapse
Affiliation(s)
- Andrea Ecker
- Department of Microbiology and Immunology, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
| | | | | | | | | |
Collapse
|
49
|
Religa AA, Waters AP. Sirtuins of parasitic protozoa: in search of function(s). Mol Biochem Parasitol 2012; 185:71-88. [PMID: 22906508 PMCID: PMC3484402 DOI: 10.1016/j.molbiopara.2012.08.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 08/01/2012] [Accepted: 08/02/2012] [Indexed: 01/09/2023]
Abstract
The SIR2 family of NAD+-dependent protein deacetylases, collectively called sirtuins, has been of central interest due to their proposed roles in life-span regulation and ageing. Sirtuins are one group of environment sensors of a cell interpreting external information and orchestrating internal responses at the sub-cellular level, through participation in gene regulation mechanisms. Remarkably conserved across all kingdoms of life SIR2 proteins in several protozoan parasites appear to have both conserved and intriguing unique functions. This review summarises our current knowledge of the members of the sirtuin families in Apicomplexa, including Plasmodium, and other protozoan parasites such as Trypanosoma and Leishmania. The wide diversity of processes regulated by SIR2 proteins makes them targets worthy of exploitation in anti-parasitic therapies.
Collapse
Affiliation(s)
- Agnieszka A Religa
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G12 8TA, UK.
| | | |
Collapse
|
50
|
Abstract
Malaria is an important human disease and is the target of a global eradication campaign. New technological and informatics advancements in population genomics are being leveraged to identify genetic loci under selection in the malaria parasite and to find variants that are associated with key clinical phenotypes, such as drug resistance. This article provides a timely Review of how population-genetics-based strategies are being applied to Plasmodium falciparum both to identify genetic loci as key targets of interventions and to develop monitoring and surveillance tools that are crucial for the successful elimination and eradication of malaria.
Collapse
|