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Domagalska MA, Barrett MP, Dujardin JC. Drug resistance in Leishmania: does it really matter? Trends Parasitol 2023; 39:251-259. [PMID: 36803859 DOI: 10.1016/j.pt.2023.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/26/2023] [Accepted: 01/27/2023] [Indexed: 02/19/2023]
Abstract
Treatment failure (TF) jeopardizes the management of parasitic diseases, including leishmaniasis. From the parasite's point of view, drug resistance (DR) is generally considered as central to TF. However, the link between TF and DR, as measured by in vitro drug susceptibility assays, is unclear, some studies revealing an association between treatment outcome and drug susceptibility, others not. Here we address three fundamental questions aiming to shed light on these ambiguities. First, are the right assays being used to measure DR? Second, are the parasites studied, which are generally those that adapt to in vitro culture, actually appropriate? Finally, are other parasite factors - such as the development of quiescent forms that are recalcitrant to drugs - responsible for TF without DR?
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Affiliation(s)
| | - Michael P Barrett
- School of Infection & Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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2
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Pilling OA, Reis-Cunha JL, Grace CA, Berry ASF, Mitchell MW, Yu JA, Malekshahi CR, Krespan E, Go CK, Lombana C, Song YS, Amorim CF, Lago AS, Carvalho LP, Carvalho EM, Brisson D, Scott P, Jeffares DC, Beiting DP. Selective whole-genome amplification reveals population genetics of Leishmania braziliensis directly from patient skin biopsies. PLoS Pathog 2023; 19:e1011230. [PMID: 36940219 PMCID: PMC10063166 DOI: 10.1371/journal.ppat.1011230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 03/30/2023] [Accepted: 02/22/2023] [Indexed: 03/21/2023] Open
Abstract
In Brazil, Leishmania braziliensis is the main causative agent of the neglected tropical disease, cutaneous leishmaniasis (CL). CL presents on a spectrum of disease severity with a high rate of treatment failure. Yet the parasite factors that contribute to disease presentation and treatment outcome are not well understood, in part because successfully isolating and culturing parasites from patient lesions remains a major technical challenge. Here we describe the development of selective whole genome amplification (SWGA) for Leishmania and show that this method enables culture-independent analysis of parasite genomes obtained directly from primary patient skin samples, allowing us to circumvent artifacts associated with adaptation to culture. We show that SWGA can be applied to multiple Leishmania species residing in different host species, suggesting that this method is broadly useful in both experimental infection models and clinical studies. SWGA carried out directly on skin biopsies collected from patients in Corte de Pedra, Bahia, Brazil, showed extensive genomic diversity. Finally, as a proof-of-concept, we demonstrated that SWGA data can be integrated with published whole genome data from cultured parasite isolates to identify variants unique to specific geographic regions in Brazil where treatment failure rates are known to be high. SWGA provides a relatively simple method to generate Leishmania genomes directly from patient samples, unlocking the potential to link parasite genetics with host clinical phenotypes.
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Affiliation(s)
- Olivia A. Pilling
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - João L. Reis-Cunha
- Department of Biology, York Biomedical Research Institute, University of York, York, United Kingdom
| | - Cooper A. Grace
- Department of Biology, York Biomedical Research Institute, University of York, York, United Kingdom
| | - Alexander S. F. Berry
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Matthew W. Mitchell
- Department of Biology, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jane A. Yu
- Computer Science Division, University of California, Berkeley, Berkeley, California, United States of America
| | - Clara R. Malekshahi
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Elise Krespan
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Christina K. Go
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Cláudia Lombana
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Yun S. Song
- Computer Science Division, University of California, Berkeley, Berkeley, California, United States of America
- Department of Statistics, University of California, Berkeley, Berkeley, California, United States of America
| | - Camila F. Amorim
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Alexsandro S. Lago
- Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil
- Laboratório de Pesquisas Clínicas do Instituto de Pesquisas Gonçalo Moniz, Fiocruz Bahia, Brazil
| | - Lucas P. Carvalho
- Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil
- Laboratório de Pesquisas Clínicas do Instituto de Pesquisas Gonçalo Moniz, Fiocruz Bahia, Brazil
| | - Edgar M. Carvalho
- Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil
- Laboratório de Pesquisas Clínicas do Instituto de Pesquisas Gonçalo Moniz, Fiocruz Bahia, Brazil
| | - Dustin Brisson
- Department of Biology, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Phillip Scott
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Daniel C. Jeffares
- Department of Biology, York Biomedical Research Institute, University of York, York, United Kingdom
| | - Daniel P. Beiting
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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3
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Novozhilova TS, Chistyakov DS, Akhmadishina LV, Lukashev AN, Gerasimov ES, Yurchenko V. Genomic analysis of Leishmania turanica strains from different regions of Central Asia. PLoS Negl Trop Dis 2023; 17:e0011145. [PMID: 36877735 PMCID: PMC10019736 DOI: 10.1371/journal.pntd.0011145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 03/16/2023] [Accepted: 02/06/2023] [Indexed: 03/07/2023] Open
Abstract
The evolution in Leishmania is governed by the opposite forces of clonality and sexual reproduction, with vicariance being an important factor. As such, Leishmania spp. populations may be monospecific or mixed. Leishmania turanica in Central Asia is a good model to compare these two types. In most areas, populations of L. turanica are mixed with L. gerbilli and L. major. Notably, co-infection with L. turanica in great gerbils helps L. major to withstand a break in the transmission cycle. Conversely, the populations of L. turanica in Mongolia are monospecific and geographically isolated. In this work, we compare genomes of several well-characterized strains of L. turanica originated from monospecific and mixed populations in Central Asia in order to shed light on genetic factors, which may drive evolution of these parasites in different settings. Our results illustrate that evolutionary differences between mixed and monospecific populations of L. turanica are not dramatic. On the level of large-scale genomic rearrangements, we confirmed that different genomic loci and different types of rearrangements may differentiate strains originated from mixed and monospecific populations, with genome translocations being the most prominent example. Our data suggests that L. turanica has a significantly higher level of chromosomal copy number variation between the strains compared to its sister species L. major with only one supernumerary chromosome. This suggests that L. turanica (in contrast to L. major) is in the active phase of evolutionary adaptation.
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Affiliation(s)
| | - Daniil S. Chistyakov
- Martsinovsky Institute of Medical Parasitology, Sechenov University, Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | | | | | - Evgeny S. Gerasimov
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
- * E-mail: (ESG); (VY)
| | - Vyacheslav Yurchenko
- Life Science Research Centre, Faculty of Science, University of Ostrava, Ostrava, Czech Republic
- * E-mail: (ESG); (VY)
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4
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Kamran M, Bhattacharjee R, Das S, Mukherjee S, Ali N. The paradigm of intracellular parasite survival and drug resistance in leishmanial parasite through genome plasticity and epigenetics: Perception and future perspective. Front Cell Infect Microbiol 2023; 13:1001973. [PMID: 36814446 PMCID: PMC9939536 DOI: 10.3389/fcimb.2023.1001973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 01/16/2023] [Indexed: 02/09/2023] Open
Abstract
Leishmania is an intracellular, zoonotic, kinetoplastid eukaryote with more than 1.2 million cases all over the world. The leishmanial chromosomes are divided into polymorphic chromosomal ends, conserved central domains, and antigen-encoding genes found in telomere-proximal regions. The genome flexibility of chromosomal ends of the leishmanial parasite is known to cause drug resistance and intracellular survival through the evasion of host defense mechanisms. Therefore, in this review, we discuss the plasticity of Leishmania genome organization which is the primary cause of drug resistance and parasite survival. Moreover, we have not only elucidated the causes of such genome plasticity which includes aneuploidy, epigenetic factors, copy number variation (CNV), and post-translation modification (PTM) but also highlighted their impact on drug resistance and parasite survival.
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Affiliation(s)
| | | | - Sonali Das
- Infectious Diseases and Immunology Division, Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Sohitri Mukherjee
- Infectious Diseases and Immunology Division, Indian Institute of Chemical Biology, Kolkata, West Bengal, India
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5
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Subspecific Nomenclature of Giardia duodenalis in the Light of a Compared Population Genomics of Pathogens. Pathogens 2023; 12:pathogens12020249. [PMID: 36839521 PMCID: PMC9960469 DOI: 10.3390/pathogens12020249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/30/2023] [Accepted: 01/30/2023] [Indexed: 02/08/2023] Open
Abstract
Genetic and genomic data have long recognized that the species Giardia duodenalis is subdivided into at least eight genetic clusters that have been named "assemblages" by specialists in the field. Some of these assemblages have been given the status of species, with Linnean binames. In the framework of the predominant clonal evolution model (PCE), we have shown that, from an evolutionary point of view, G. duodenalis assemblages are equatable to "near-clades", that is to say: clades whose discreteness is somewhat clouded by occasional genetic exchange, but remain discrete and stable in space and time. The implications of this evolutionary status for the species described within G. duodenalis are discussed in light of the most recent genetic and genomic studies. The pattern of this species' subspecific genetic variability and genetic clustering appears to be very similar to the ones of various parasitic, fungal and bacteria species. This underlines the relevance of a compared population genomics of pathogenic species allowed by the broad framework of the PCE model.
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Black JA, Reis-Cunha JL, Cruz AK, Tosi LR. Life in plastic, it's fantastic! How Leishmania exploit genome instability to shape gene expression. Front Cell Infect Microbiol 2023; 13:1102462. [PMID: 36779182 PMCID: PMC9910336 DOI: 10.3389/fcimb.2023.1102462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/05/2023] [Indexed: 01/27/2023] Open
Abstract
Leishmania are kinetoplastid pathogens that cause leishmaniasis, a debilitating and potentially life-threatening infection if untreated. Unusually, Leishmania regulate their gene expression largely post-transcriptionally due to the arrangement of their coding genes into polycistronic transcription units that may contain 100s of functionally unrelated genes. Yet, Leishmania are capable of rapid and responsive changes in gene expression to challenging environments, often instead correlating with dynamic changes in their genome composition, ranging from chromosome and gene copy number variations to the generation of extrachromosomal DNA and the accumulation of point mutations. Typically, such events indicate genome instability in other eukaryotes, coinciding with genetic abnormalities, but for Leishmania, exploiting these products of genome instability can provide selectable substrates to catalyse necessary gene expression changes by modifying gene copy number. Unorthodox DNA replication, DNA repair, replication stress factors and DNA repeats are recognised in Leishmania as contributors to this intrinsic instability, but how Leishmania regulate genome plasticity to enhance fitness whilst limiting toxic under- or over-expression of co-amplified and co-transcribed genes is unclear. Herein, we focus on fresh, and detailed insights that improve our understanding of genome plasticity in Leishmania. Furthermore, we discuss emerging models and factors that potentially circumvent regulatory issues arising from polycistronic transcription. Lastly, we highlight key gaps in our understanding of Leishmania genome plasticity and discuss future studies to define, in higher resolution, these complex regulatory interactions.
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Affiliation(s)
- Jennifer A. Black
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil,The Wellcome Centre for Integrative Parasitology, School of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom,*Correspondence: Luiz. R.O. Tosi, ; Jennifer A. Black,
| | | | - Angela. K. Cruz
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Luiz. R.O. Tosi
- Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil,*Correspondence: Luiz. R.O. Tosi, ; Jennifer A. Black,
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7
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Santi AMM, Murta SMF. Impact of Genetic Diversity and Genome Plasticity of Leishmania spp. in Treatment and the Search for Novel Chemotherapeutic Targets. Front Cell Infect Microbiol 2022; 12:826287. [PMID: 35141175 PMCID: PMC8819175 DOI: 10.3389/fcimb.2022.826287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/04/2022] [Indexed: 11/21/2022] Open
Abstract
Leishmaniasis is one of the major public health concerns in Latin America, Africa, Asia, and Europe. The absence of vaccines for human use and the lack of effective vector control programs make chemotherapy the main strategy to control all forms of the disease. However, the high toxicity of available drugs, limited choice of therapeutic agents, and occurrence of drug-resistant parasite strains are the main challenges related to chemotherapy. Currently, only a small number of drugs are available for leishmaniasis treatment, including pentavalent antimonials (SbV), amphotericin B and its formulations, miltefosine, paromomycin sulphate, and pentamidine isethionate. In addition to drug toxicity, therapeutic failure of leishmaniasis is a serious concern. The occurrence of drug-resistant parasites is one of the causes of therapeutic failure and is closely related to the diversity of parasites in this genus. Owing to the enormous plasticity of the genome, resistance can occur by altering different metabolic pathways, demonstrating that resistance mechanisms are multifactorial and extremely complex. Genetic variability and genome plasticity cause not only the available drugs to have limitations, but also make the search for new drugs challenging. Here, we examined the biological characteristics of parasites that hinder drug discovery.
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8
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Glans H, Lind Karlberg M, Advani R, Bradley M, Alm E, Andersson B, Downing T. High genome plasticity and frequent genetic exchange in Leishmania tropica isolates from Afghanistan, Iran and Syria. PLoS Negl Trop Dis 2021; 15:e0010110. [PMID: 34968388 PMCID: PMC8754299 DOI: 10.1371/journal.pntd.0010110] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/12/2022] [Accepted: 12/17/2021] [Indexed: 11/23/2022] Open
Abstract
Background The kinetoplastid protozoan Leishmania tropica mainly causes cutaneous leishmaniasis in humans in the Middle East, and relapse or treatment failure after treatment are common in this area. L. tropica’s digenic life cycle includes distinct stages in the vector sandfly and the mammalian host. Sexual reproduction and genetic exchange appear to occur more frequently than in other Leishmania species. Understanding these processes is complicated by chromosome instability during cell division that yields aneuploidy, recombination and heterozygosity. This combination of rare recombination and aneuploid permits may reveal signs of hypothetical parasexual mating, where diploid cells fuse to form a transient tetraploid that undergoes chromosomal recombination and gradual chromosomal loss. Methodology/principal findings The genome-wide SNP diversity from 22 L. tropica isolates showed chromosome-specific runs of patchy heterozygosity and extensive chromosome copy number variation. All these isolates were collected during 2007–2017 in Sweden from patients infected in the Middle East and included isolates from a patient possessing two genetically distinct leishmaniasis infections three years apart with no evidence of re-infection. We found differing ancestries on the same chromosome (chr36) across multiple samples: matching the reference genome with few derived alleles, followed by blocks of heterozygous SNPs, and then by clusters of homozygous SNPs with specific recombination breakpoints at an inferred origin of replication. Other chromosomes had similar marked changes in heterozygosity at strand-switch regions separating polycistronic transcriptional units. Conclusion/significance These large-scale intra- and inter-chromosomal changes in diversity driven by recombination and aneuploidy suggest multiple mechanisms of cell reproduction and diversification in L. tropica, including mitotic, meiotic and parasexual processes. It underpins the need for more genomic surveillance of Leishmania, to detect emerging hybrids that could spread more widely and to better understand the association between genetic variation and treatment outcome. Furthering our understanding of Leishmania genome evolution and ancestry will aid better diagnostics and treatment for cutaneous leishmaniasis caused by L.tropica in the Middle East. Cutaneous leishmaniasis is mainly caused by Leishmania tropica in the Middle East, where it is known for treatment failure and a need for prolonged and/or multiple treatments. Several factors affect the clinical presentation and treatment outcome, such as host genetic variability and specific immune response, as well as environmental factors and the vector species. Little is known about the parasite genome and its influence on treatment response. By analysing the genome of 22 isolates of L. tropica, we have revealed extensive genomic variation and a complex population structure with evidence of genetic exchange within and among the isolates, indicating a possible presence of sexual or parasexual mechanisms. Understanding the Leishmania genome better may improve future treatment and better understanding of treatment failure and relapse.
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Affiliation(s)
- Hedvig Glans
- Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
- Division of Dermatology & Venerology, Dept of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
| | - Maria Lind Karlberg
- Department of Microbiology, The Public Health Agency of Sweden, Stockholm, Sweden
| | - Reza Advani
- Department of Microbiology, The Public Health Agency of Sweden, Stockholm, Sweden
| | - Maria Bradley
- Division of Dermatology & Venerology, Dept of Medicine Solna, Karolinska Institutet, Stockholm, Sweden
- Department of Dermatology and Venerology, Karolinska University Hospital, Stockholm, Sweden
| | - Erik Alm
- The European Center for Disease Prevention and Control, Stockholm, Sweden
| | - Björn Andersson
- Department of Cell & Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Tim Downing
- School of Biotechnology, Dublin City University, Dublin, Ireland
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9
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Negreira GH, Monsieurs P, Imamura H, Maes I, Kuk N, Yagoubat A, Van den Broeck F, Sterkers Y, Dujardin JC, Domagalska MA. High throughput single-cell genome sequencing gives insights into the generation and evolution of mosaic aneuploidy in Leishmania donovani. Nucleic Acids Res 2021; 50:293-305. [PMID: 34893872 PMCID: PMC8886908 DOI: 10.1093/nar/gkab1203] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 11/17/2021] [Accepted: 11/23/2021] [Indexed: 11/14/2022] Open
Abstract
Leishmania, a unicellular eukaryotic parasite, is a unique model
for aneuploidy and cellular heterogeneity, along with their potential role in
adaptation to environmental stresses. Somy variation within clonal populations
was previously explored in a small subset of chromosomes using fluorescence
hybridization methods. This phenomenon, termed mosaic aneuploidy (MA), might
have important evolutionary and functional implications but remains
under-explored due to technological limitations. Here, we applied and validated
a high throughput single-cell genome sequencing method to study for the first
time the extent and dynamics of whole karyotype heterogeneity in two clonal
populations of Leishmania promastigotes representing different
stages of MA evolution in vitro. We found that drastic changes
in karyotypes quickly emerge in a population stemming from an almost euploid
founder cell. This possibly involves polyploidization/hybridization at an early
stage of population expansion, followed by assorted ploidy reduction. During
further stages of expansion, MA increases by moderate and gradual karyotypic
alterations, affecting a defined subset of chromosomes. Our data provide the
first complete characterization of MA in Leishmania and pave
the way for further functional studies.
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Affiliation(s)
- Gabriel H Negreira
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Pieter Monsieurs
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Hideo Imamura
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Ilse Maes
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium
| | - Nada Kuk
- MiVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Akila Yagoubat
- MiVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Frederik Van den Broeck
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium.,Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, Katholieke Universiteit Leuven, 3000 Leuven, Belgium
| | - Yvon Sterkers
- MiVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Jean-Claude Dujardin
- Molecular Parasitology Unit, Institute of Tropical Medicine, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Belgium
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10
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Espada CR, Quilles JC, Albuquerque-Wendt A, Cruz MC, Beneke T, Lorenzon LB, Gluenz E, Cruz AK, Uliana SRB. Effective Genome Editing in Leishmania ( Viannia) braziliensis Stably Expressing Cas9 and T7 RNA Polymerase. Front Cell Infect Microbiol 2021; 11:772311. [PMID: 34858879 PMCID: PMC8631273 DOI: 10.3389/fcimb.2021.772311] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/19/2021] [Indexed: 12/15/2022] Open
Abstract
Until 2015, loss-of-function studies to elucidate protein function in Leishmania relied on gene disruption through homologous recombination. Then, the CRISPR/Cas9 revolution reached these protozoan parasites allowing efficient genome editing with one round of transfection. In addition, the development of LeishGEdit, a PCR-based toolkit for generating knockouts and tagged lines using CRISPR/Cas9, allowed a more straightforward and effective genome editing. In this system, the plasmid pTB007 is delivered to Leishmania for episomal expression or integration in the β-tubulin locus and for the stable expression of T7 RNA polymerase and Cas9. In South America, and especially in Brazil, Leishmania (Viannia) braziliensis is the most frequent etiological agent of tegumentary leishmaniasis. The L. braziliensis β-tubulin locus presents significant sequence divergence in comparison with Leishmania major, which precludes the efficient integration of pTB007 and the stable expression of Cas9. To overcome this limitation, the L. major β-tubulin sequences, present in the pTB007, were replaced by a Leishmania (Viannia) β-tubulin conserved sequence generating the pTB007_Viannia plasmid. This modification allowed the successful integration of the pTB007_Viannia cassette in the L. braziliensis M2903 genome, and in silico predictions suggest that this can also be achieved in other Viannia species. The activity of Cas9 was evaluated by knocking out the flagellar protein PF16, which caused a phenotype of immobility in these transfectants. Endogenous PF16 was also successfully tagged with mNeonGreen, and an in-locus complementation strategy was employed to return a C-terminally tagged copy of the PF16 gene to the original locus, which resulted in the recovery of swimming capacity. The modified plasmid pTB007_Viannia allowed the integration and stable expression of both T7 RNA polymerase and Cas9 in L. braziliensis and provided an important tool for the study of the biology of this parasite.
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Affiliation(s)
- Caroline R Espada
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil.,Departamento de Biologia Celular e Molecular, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (FMRP-USP), Ribeirão Preto, Brazil
| | - José Carlos Quilles
- Departamento de Biologia Celular e Molecular, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (FMRP-USP), Ribeirão Preto, Brazil
| | - Andreia Albuquerque-Wendt
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.,Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Global Health and Tropical Medicine (GHTM), Instituto de Higiene e Medicina Tropical (IHTM), Universidade de Lisboa (UNL), Lisbon, Portugal
| | - Mario C Cruz
- Centro de Facilidades para Apoio à Pesquisa, Universidade de São Paulo (CEFAP-USP), São Paulo, Brazil
| | - Tom Beneke
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Lucas B Lorenzon
- Departamento de Biologia Celular e Molecular, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (FMRP-USP), Ribeirão Preto, Brazil
| | - Eva Gluenz
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.,Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity & Inflammation, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Angela K Cruz
- Departamento de Biologia Celular e Molecular, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (FMRP-USP), Ribeirão Preto, Brazil
| | - Silvia R B Uliana
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
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11
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Leishmania and the Model of Predominant Clonal Evolution. Microorganisms 2021; 9:microorganisms9112409. [PMID: 34835534 PMCID: PMC8620605 DOI: 10.3390/microorganisms9112409] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/18/2021] [Accepted: 11/20/2021] [Indexed: 01/23/2023] Open
Abstract
As it is the case for other pathogenic microorganisms, the respective impact of clonality and genetic exchange on Leishmania natural populations has been the object of lively debates since the early 1980s. The predominant clonal evolution (PCE) model states that genetic exchange in these parasites’ natural populations may have a high relevance on an evolutionary scale, but is not sufficient to erase a persistent phylogenetic signal and the existence of bifurcating trees. Recent data based on high-resolution markers and genomic polymorphisms fully confirm the PCE model down to a microevolutionary level.
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12
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Reproduction in Trypanosomatids: Past and Present. BIOLOGY 2021; 10:biology10060471. [PMID: 34071741 PMCID: PMC8230138 DOI: 10.3390/biology10060471] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 01/07/2023]
Abstract
Simple Summary The reproduction of trypanosomatids is a fundamental issue for host–parasite interaction, and its biological importance lies in knowing how these species acquire new defense mechanisms against the countermeasures imposed by the host, which is consistent with the theory of the endless race or the Red Queen hypothesis for the existence of meiotic sex. Moreover, the way these species re-produce may also be at the origin of novel and more virulent clades and is relevant from a thera-peutic or vaccination point of view, as sex may contribute to increased tolerance and even to the rapid acquisition of drug resistance mechanisms. Kinetoplastids are single-celled organisms, many of them being responsible for important parasitic diseases, globally termed neglected diseases, which are endemic in low-income countries. Leishmaniasis, African (sleeping sickness) and American trypanosomiasis (Chagas disease) caused by trypanosomatids are among the most ne-glected tropical scourges related to poverty and poor health systems. The reproduction of these microorganisms has long been considered to be clonal due to population genetic observations. However, there is increasing evidence of true sex and genetic exchange events under laboratory conditions. We would like to highlight the importance of this topic in the field of host/parasite in-terplay, virulence, and drug resistance. Abstract Diseases caused by trypanosomatids (Sleeping sickness, Chagas disease, and leishmaniasis) are a serious public health concern in low-income endemic countries. These diseases are produced by single-celled parasites with a diploid genome (although aneuploidy is frequent) organized in pairs of non-condensable chromosomes. To explain the way they reproduce through the analysis of natural populations, the theory of strict clonal propagation of these microorganisms was taken as a rule at the beginning of the studies, since it partially justified their genomic stability. However, numerous experimental works provide evidence of sexual reproduction, thus explaining certain naturally occurring events that link the number of meiosis per mitosis and the frequency of mating. Recent techniques have demonstrated genetic exchange between individuals of the same species under laboratory conditions, as well as the expression of meiosis specific genes. The current debate focuses on the frequency of genomic recombination events and its impact on the natural parasite population structure. This paper reviews the results and techniques used to demonstrate the existence of sex in trypanosomatids, the inheritance of kinetoplast DNA (maxi- and minicircles), the impact of genetic exchange in these parasites, and how it can contribute to the phenotypic diversity of natural populations.
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da Silva MS. DNA Double-Strand Breaks: A Double-Edged Sword for Trypanosomatids. Front Cell Dev Biol 2021; 9:669041. [PMID: 33937271 PMCID: PMC8085331 DOI: 10.3389/fcell.2021.669041] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 03/29/2021] [Indexed: 01/09/2023] Open
Abstract
For nearly all eukaryotic cells, stochastic DNA double-strand breaks (DSBs) are one of the most deleterious types of DNA lesions. DSB processing and repair can cause sequence deletions, loss of heterozygosity, and chromosome rearrangements resulting in cell death or carcinogenesis. However, trypanosomatids (single-celled eukaryotes parasites) do not seem to follow this premise strictly. Several studies have shown that trypanosomatids depend on DSBs to perform several events of paramount importance during their life cycle. For Trypanosoma brucei, DSBs formation is associated with host immune evasion via antigenic variation. In Trypanosoma cruzi, DSBs play a crucial role in the genetic exchange, a mechanism that is still little explored but appear to be of fundamental importance for generating variability. In Leishmania spp., DSBs are necessary to generate genomic changes by gene copy number variation (CNVs), events that are essential for these organisms to overcome inhospitable conditions. As DSB repair in trypanosomatids is primarily conducted via homologous recombination (HR), most of the events associated with DSBs are HR-dependent. This review will discuss the latest findings on how trypanosomatids balance the benefits and inexorable challenges caused by DSBs.
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Affiliation(s)
- Marcelo Santos da Silva
- DNA Replication and Repair Laboratory (DRRL), Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, Brazil
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14
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Briggs EM, Marques CA, Reis-Cunha J, Black J, Campbell S, Damasceno J, Bartholomeu D, Crouch K, McCulloch R. Next-Generation Analysis of Trypanosomatid Genome Stability and Instability. Methods Mol Biol 2021; 2116:225-262. [PMID: 32221924 DOI: 10.1007/978-1-0716-0294-2_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Understanding the rate and patterns of genome variation is becoming ever more amenable to whole-genome analysis through advances in DNA sequencing, which may, at least in some circumstances, have supplanted more localized analyses by cellular and genetic approaches. Whole-genome analyses can utilize both short- and long-read sequence technologies. Here we describe how sequence generated by these approaches has been used in trypanosomatids to examine DNA replication dynamics, the accumulation of modified histone H2A due to genome damage, and evaluation of genome variation, focusing on ploidy change.
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Affiliation(s)
- Emma M Briggs
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Catarina A Marques
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Joao Reis-Cunha
- Departamento de Parasitologia, Universidade Federal de Minas Gerais-Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Jennifer Black
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Samantha Campbell
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Jeziel Damasceno
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Daniella Bartholomeu
- Departamento de Parasitologia, Universidade Federal de Minas Gerais-Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Kathryn Crouch
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Richard McCulloch
- Institute of Infection, Immunity and Inflammation, The Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK.
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Tibayrenc M, Ayala FJ. Models in parasite and pathogen evolution: Genomic analysis reveals predominant clonality and progressive evolution at all evolutionary scales in parasitic protozoa, yeasts and bacteria. ADVANCES IN PARASITOLOGY 2021; 111:75-117. [PMID: 33482977 DOI: 10.1016/bs.apar.2020.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The predominant clonal evolution (PCE) model of pathogenic microorganisms postulates that the impact of genetic recombination in those pathogens' natural populations is not enough to erase a persistent phylogenetic signal at all evolutionary scales from microevolution till geological times in the whole ecogeographical range of the species considered. We have tested this model with a set of representative parasitic protozoa, yeasts and bacteria in the light of the most recent genomic data. All surveyed species, including those that were considered as highly recombining, exhibit similar PCE patterns above and under the species level, from macro- to micro-evolutionary scales (Russian doll pattern), suggesting gradual evolution. To our knowledge, it is the first time that such a strong common evolutionary feature among very diverse pathogens has been evidenced. The implications of this model for basic biology and applied research are exposed. These implications include our knowledge on the pathogens' reproductive mode, their population structure, the possibility to type strain and to follow up epidemics (molecular epidemiology) and to revisit pathogens' taxonomy through a flexible use of the phylogenetic species concept (Cracraft, 1983).
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Affiliation(s)
- Michel Tibayrenc
- Maladies Infectieuses et Vecteurs Ecologie, Génétique, Evolution et Contrôle, MIVEGEC (IRD 224-CNRS 5290-UM1-UM2), Institut de recherche pour le développement, Montpellier Cedex 5, France.
| | - Francisco J Ayala
- Catedra Francisco Jose Ayala of Science, Technology, and Religion, University of Comillas, Madrid, Spain; 2 Locke Court, Irvine, CA, United States
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Grünebast J, Clos J. Leishmania: Responding to environmental signals and challenges without regulated transcription. Comput Struct Biotechnol J 2020; 18:4016-4023. [PMID: 33363698 PMCID: PMC7744640 DOI: 10.1016/j.csbj.2020.11.058] [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: 08/31/2020] [Revised: 11/24/2020] [Accepted: 11/28/2020] [Indexed: 02/06/2023] Open
Abstract
Here we describe the non-canonical control of gene expression in Leishmania, a single-cell parasite that is responsible for one of the major neglected tropical diseases. We discuss the lack of regulated RNA synthesis, the post-transcriptional gene regulation including RNA stability and regulated translation. We also show that genetic adaptations such as mosaic aneuploidy, gene copy number variations and DNA sequence polymorphisms are important means for overcoming drug challenge and environmental diversity. These mechanisms are discussed in the context of the unique flow of genetic information found in Leishmania and related protists.
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Affiliation(s)
- Janne Grünebast
- Leishmaniasis Group, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Joachim Clos
- Leishmaniasis Group, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
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Kröber-Boncardo C, Lorenzen S, Brinker C, Clos J. Casein kinase 1.2 over expression restores stress resistance to Leishmania donovani HSP23 null mutants. Sci Rep 2020; 10:15969. [PMID: 32994468 PMCID: PMC7525241 DOI: 10.1038/s41598-020-72724-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 09/04/2020] [Indexed: 01/25/2023] Open
Abstract
Leishmania donovani is a trypanosomatidic parasite and causes the lethal kala-azar fever, a neglected tropical disease. The Trypanosomatida are devoid of transcriptional gene regulation and rely on gene copy number variations and translational control for their adaption to changing conditions. To survive at mammalian tissue temperatures, L. donovani relies on the small heat shock protein HSP23, the loss of which renders the parasites stress sensitive and impairs their proliferation. Here, we analysed a spontaneous escape mutant with wild type-like in vitro growth. Further selection of this escape strains resulted in a complete reversion of the phenotype. Whole genome sequencing revealed a correlation between stress tolerance and the massive amplification of a six-gene cluster on chromosome 35, with further analysis showing over expression of the casein kinase 1.2 gene as responsible. In vitro phosphorylation experiments established both HSP23 and the related P23 co-chaperone as substrates and modulators of casein kinase 1.2, providing evidence for another crucial link between chaperones and signal transduction protein kinases in this early branching eukaryote.
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Affiliation(s)
- Constanze Kröber-Boncardo
- Leishmania Group, Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany
| | - Stephan Lorenzen
- Department of Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Christine Brinker
- Leishmania Group, Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany
| | - Joachim Clos
- Leishmania Group, Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany.
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Damasceno JD, Marques CA, Black J, Briggs E, McCulloch R. Read, Write, Adapt: Challenges and Opportunities during Kinetoplastid Genome Replication. Trends Genet 2020; 37:21-34. [PMID: 32993968 PMCID: PMC9213392 DOI: 10.1016/j.tig.2020.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/31/2022]
Abstract
The genomes of all organisms are read throughout their growth and development, generating new copies during cell division and encoding the cellular activities dictated by the genome’s content. However, genomes are not invariant information stores but are purposefully altered in minor and major ways, adapting cellular behaviour and driving evolution. Kinetoplastids are eukaryotic microbes that display a wide range of such read–write genome activities, in many cases affecting critical aspects of their biology, such as host adaptation. Here we discuss the range of read–write genome changes found in two well-studied kinetoplastid parasites, Trypanosoma brucei and Leishmania, focusing on recent work that suggests such adaptive genome variation is linked to novel strategies the parasites use to replicate their unconventional genomes. Polycistronic transcription dominates and shapes kinetoplastid genomes, inevitably leading to clashes with DNA replication. By harnessing the resultant DNA damage for adaptation, kinetoplastids have huge potential for dynamic read–write genome variation. Major origins of DNA replication are confined to the boundaries of polycistronic transcription units in the Trypanosoma brucei and Leishmania genomes, putatively limiting DNA damage. Subtelomeres may lack this arrangement, generating read–write hotspots. In T. brucei, early replication of the highly transcribed subtelomeric variant surface glycoprotein (VSG) expression site may ensure replication-transcription clashes within this site to trigger DNA recombination, an event critical for antigenic variation. Leishmania genomes show extensive aneuploidy and copy number variation. Notably, DNA replication requires recombination factors and relies on post-S phase replication of subtelomeres. Evolution of compartmentalised DNA replication programmes underpin important aspects of genome biology in kinetoplastids, illustrating the consolidation of genome maintenance strategies to promote genome plasticity.
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Affiliation(s)
- Jeziel D Damasceno
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK.
| | - Catarina A Marques
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK
| | - Jennifer Black
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK
| | - Emma Briggs
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK; Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Richard McCulloch
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, G12 8TA, UK.
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Damasceno JD, Reis-Cunha J, Crouch K, Beraldi D, Lapsley C, Tosi LRO, Bartholomeu D, McCulloch R. Conditional knockout of RAD51-related genes in Leishmania major reveals a critical role for homologous recombination during genome replication. PLoS Genet 2020; 16:e1008828. [PMID: 32609721 PMCID: PMC7360064 DOI: 10.1371/journal.pgen.1008828] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 07/14/2020] [Accepted: 05/05/2020] [Indexed: 12/12/2022] Open
Abstract
Homologous recombination (HR) has an intimate relationship with genome replication, both during repair of DNA lesions that might prevent DNA synthesis and in tackling stalls to the replication fork. Recent studies led us to ask if HR might have a more central role in replicating the genome of Leishmania, a eukaryotic parasite. Conflicting evidence has emerged regarding whether or not HR genes are essential, and genome-wide mapping has provided evidence for an unorthodox organisation of DNA replication initiation sites, termed origins. To answer this question, we have employed a combined CRISPR/Cas9 and DiCre approach to rapidly generate and assess the effect of conditional ablation of RAD51 and three RAD51-related proteins in Leishmania major. Using this approach, we demonstrate that loss of any of these HR factors is not immediately lethal but in each case growth slows with time and leads to DNA damage and accumulation of cells with aberrant DNA content. Despite these similarities, we show that only loss of RAD51 or RAD51-3 impairs DNA synthesis and causes elevated levels of genome-wide mutation. Furthermore, we show that these two HR factors act in distinct ways, since ablation of RAD51, but not RAD51-3, has a profound effect on DNA replication, causing loss of initiation at the major origins and increased DNA synthesis at subtelomeres. Our work clarifies questions regarding the importance of HR to survival of Leishmania and reveals an unanticipated, central role for RAD51 in the programme of genome replication in a microbial eukaryote.
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Affiliation(s)
- Jeziel D. Damasceno
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, United Kingdom
- * E-mail: (JDD); (RM)
| | - João Reis-Cunha
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Kathryn Crouch
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, United Kingdom
| | - Dario Beraldi
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, United Kingdom
| | - Craig Lapsley
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, United Kingdom
| | - Luiz R. O. Tosi
- Department of Cell and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo; Ribeirão Preto, SP, Brazil
| | - Daniella Bartholomeu
- Laboratório de Imunologia e Genômica de Parasitos, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Richard McCulloch
- The Wellcome Centre for Integrative Parasitology, University of Glasgow, Institute of Infection, Immunity and Inflammation, Sir Graeme Davies Building, 120 University Place, Glasgow, United Kingdom
- * E-mail: (JDD); (RM)
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Cotton JA, Durrant C, Franssen SU, Gelanew T, Hailu A, Mateus D, Sanders MJ, Berriman M, Volf P, Miles MA, Yeo M. Genomic analysis of natural intra-specific hybrids among Ethiopian isolates of Leishmania donovani. PLoS Negl Trop Dis 2020; 14:e0007143. [PMID: 32310945 PMCID: PMC7237039 DOI: 10.1371/journal.pntd.0007143] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 05/19/2020] [Accepted: 12/24/2019] [Indexed: 12/30/2022] Open
Abstract
Parasites of the genus Leishmania (Kinetoplastida: Trypanosomatidae) cause widespread and devastating human diseases. Visceral leishmaniasis due to Leishmania donovani is endemic in Ethiopia where it has also been responsible for major epidemics. The presence of hybrid genotypes has been widely reported in surveys of natural populations, genetic variation reported in a number of Leishmania species, and the extant capacity for genetic exchange demonstrated in laboratory experiments. However, patterns of recombination and the evolutionary history of admixture that produced these hybrid populations remain unclear. Here, we use whole-genome sequence data to investigate Ethiopian L. donovani isolates previously characterized as hybrids by microsatellite and multi-locus sequencing. To date there is only one previous study on a natural population of Leishmania hybrids based on whole-genome sequences. We propose that these hybrids originate from recombination between two different lineages of Ethiopian L. donovani occurring in the same region. Patterns of inheritance are more complex than previously reported with multiple, apparently independent, origins from similar parents that include backcrossing with parental types. Analysis indicates that hybrids are representative of at least three different histories. Furthermore, isolates were highly polysomic at the level of chromosomes with differences between parasites recovered from a recrudescent infection from a previously treated individual. The results demonstrate that recombination is a significant feature of natural populations and contributes to the growing body of data that shows how recombination, and gene flow, shape natural populations of Leishmania.
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Affiliation(s)
| | | | | | - Tesfaye Gelanew
- Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
| | - Asrat Hailu
- Faculty of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
| | - David Mateus
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Michael A. Miles
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew Yeo
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Franssen SU, Durrant C, Stark O, Moser B, Downing T, Imamura H, Dujardin JC, Sanders MJ, Mauricio I, Miles MA, Schnur LF, Jaffe CL, Nasereddin A, Schallig H, Yeo M, Bhattacharyya T, Alam MZ, Berriman M, Wirth T, Schönian G, Cotton JA. Global genome diversity of the Leishmania donovani complex. eLife 2020; 9:e51243. [PMID: 32209228 PMCID: PMC7105377 DOI: 10.7554/elife.51243] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/27/2020] [Indexed: 12/30/2022] Open
Abstract
Protozoan parasites of the Leishmania donovani complex - L. donovani and L. infantum - cause the fatal disease visceral leishmaniasis. We present the first comprehensive genome-wide global study, with 151 cultured field isolates representing most of the geographical distribution. L. donovani isolates separated into five groups that largely coincide with geographical origin but vary greatly in diversity. In contrast, the majority of L. infantum samples fell into one globally-distributed group with little diversity. This picture is complicated by several hybrid lineages. Identified genetic groups vary in heterozygosity and levels of linkage, suggesting different recombination histories. We characterise chromosome-specific patterns of aneuploidy and identified extensive structural variation, including known and suspected drug resistance loci. This study reveals greater genetic diversity than suggested by geographically-focused studies, provides a resource of genomic variation for future work and sets the scene for a new understanding of the evolution and genetics of the Leishmania donovani complex.
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Affiliation(s)
| | - Caroline Durrant
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
| | | | | | - Tim Downing
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
- Dublin City UniversityDublinIreland
| | | | - Jean-Claude Dujardin
- Institute of Tropical MedicineAntwerpBelgium
- Department of Biomedical Sciences, University of AntwerpAntwerpBelgium
| | - Mandy J Sanders
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
| | - Isabel Mauricio
- Universidade Nova de Lisboa Instituto de Higiene e MedicinaLisboaPortugal
| | - Michael A Miles
- London School of Hygiene and Tropical MedicineLondonUnited Kingdom
| | - Lionel F Schnur
- Kuvin Centre for the Study of Infectious and Tropical Diseases, IMRIC, Hebrew University-Hadassah, Medical SchoolJerusalemIsrael
| | - Charles L Jaffe
- Kuvin Centre for the Study of Infectious and Tropical Diseases, IMRIC, Hebrew University-Hadassah, Medical SchoolJerusalemIsrael
| | - Abdelmajeed Nasereddin
- Kuvin Centre for the Study of Infectious and Tropical Diseases, IMRIC, Hebrew University-Hadassah, Medical SchoolJerusalemIsrael
| | - Henk Schallig
- Amsterdam University Medical Centres – Academic Medical Centre at the University of Amsterdam, Department of Medical Microbiology – Experimental ParasitologyAmsterdamNetherlands
| | - Matthew Yeo
- London School of Hygiene and Tropical MedicineLondonUnited Kingdom
| | | | - Mohammad Z Alam
- Department of Parasitology, Bangladesh Agricultural UniversityMymensinghBangladesh
| | - Matthew Berriman
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
| | - Thierry Wirth
- Institut de Systématique, Evolution, Biodiversité, ISYEB, Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des AntillesParisFrance
- École Pratique des Hautes Études (EPHE)Paris Sciences & Lettres (PSL)ParisFrance
| | | | - James A Cotton
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
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Single-Strand Annealing Plays a Major Role in Double-Strand DNA Break Repair following CRISPR-Cas9 Cleavage in Leishmania. mSphere 2019; 4:4/4/e00408-19. [PMID: 31434745 PMCID: PMC6706467 DOI: 10.1128/msphere.00408-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
CRISPR-Cas9 genome editing relies on an efficient double-strand DNA break (DSB) and repair. Contrary to mammalian cells, the protozoan parasite Leishmania lacks the most efficient nonhomologous end-joining pathway and uses microhomology-mediated end joining (MMEJ) and, occasionally, homology-directed repair to repair DSBs. Here, we reveal that Leishmania predominantly uses single-strand annealing (SSA) (>90%) instead of MMEJ (<10%) for DSB repair (DSBR) following CRISPR targeting of the miltefosine transporter gene, resulting in 9-, 18-, 20-, and 29-kb sequence deletions and multiple gene codeletions. Strikingly, when targeting the Leishmania donovani LdBPK_241510 gene, SSA even occurred by using direct repeats 77 kb apart, resulting in the codeletion of 15 Leishmania genes, though with a reduced frequency. These data strongly indicate that DSBR is not efficient in Leishmania, which explains why more than half of DSBs led to cell death and why the CRISPR gene-targeting efficiency is low compared with that in other organisms. Since direct repeat sequences are widely distributed in the Leishmania genome, we predict that many DSBs created by CRISPR are repaired by SSA. It is also revealed that DNA polymerase theta is involved in both MMEJ and SSA in Leishmania Collectively, this study establishes that DSBR mechanisms and their competence in an organism play an important role in determining the outcome and efficacy of CRISPR gene targeting. These observations emphasize the use of donor DNA templates to improve gene editing specificity and efficiency in Leishmania In addition, we developed a novel Staphylococcus aureus Cas9 constitutive expression vector (pLdSaCN) for gene targeting in Leishmania IMPORTANCE Due to differences in double-strand DNA break (DSB) repair mechanisms, CRISPR-Cas9 gene editing efficiency can vary greatly in different organisms. In contrast to mammalian cells, the protozoan parasite Leishmania uses microhomology-mediated end joining (MMEJ) and, occasionally, homology-directed repair (HDR) to repair DSBs but lacks the nonhomologous end-joining pathway. Here, we show that Leishmania predominantly uses single-strand annealing (SSA) instead of MMEJ for DSB repairs (DSBR), resulting in large deletions that can include multiple genes. This strongly indicates that the overall DSBR in Leishmania is inefficient and therefore can influence the outcome of CRISPR-Cas9 gene editing, highlighting the importance of using a donor DNA to improve gene editing fidelity and efficiency in Leishmania.
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Jayasena Kaluarachchi TD, Weerasekera MM, McBain AJ, Ranasinghe S, Wickremasinghe R, Yasawardene S, Jayanetti N, Wickremasinghe R. Diagnosing Cutaneous leishmaniasis using Fluorescence in Situ Hybridization: the Sri Lankan Perspective. Pathog Glob Health 2019; 113:180-190. [PMID: 31429388 DOI: 10.1080/20477724.2019.1650228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Cutaneous leishmaniasis (CL) caused by Leishmania donovani MON-37 is becoming a major public health problem in Sri Lanka, with 100 new cases per month being reported in endemic regions. Diagnosis of CL is challenging for several reasons. Due to relative specificity and rapidity we propose Fluorescence in Situ Hybridization as a diagnostic tool for CL. The objective was to evaluate the potential of Fluorescence in Situ Hybridization as a diagnostic method for Cutaneous leishmaniasis in Sri Lanka. Literature on current laboratory tests used to diagnose Cutaneous leishmaniasis in Sri Lanka and globally was reviewed. Sri Lankan data were reviewed systematically following the PRISMA guidelines. A narrative of the results is presented. There is currently no gold standard diagnostic method for Cutaneous leishmaniasis. Fluorescence in Situ Hybridization has been previously applied to detect dermal pathologies including those involving infectious agents, and its use to detect the Leishmania parasite in human cutaneous lesions reported in small number of studies, generally with limited numbers of subjects. Advantages of FISH has been specificity, cost and ease-of-use compared to the alternatives. Based on the available literature and our current work, FISH has potential for diagnosing CL and should now be evaluated in larger cohorts in endemic regions. FISH for CL diagnosis could find application in countries such as Sri Lanka, where laboratory facilities may be limited in rural areas where the disease burden is highest.
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Affiliation(s)
| | - Manjula Manoji Weerasekera
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayewardenepura , Nugegoda , Sri Lanka
| | - Andrew J McBain
- Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayewardenepura , Nugegoda , Sri Lanka.,Division of Pharmacy & Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, The University of Manchester , Manchester
| | - Shalindra Ranasinghe
- Department of Parasitology, Faculty of Medical Sciences, University of Sri Jayewardenepura , Colombo , Sri Lanka
| | - Renu Wickremasinghe
- Department of Parasitology, Faculty of Medical Sciences, University of Sri Jayewardenepura , Colombo , Sri Lanka
| | - Surangi Yasawardene
- Department of Anatomy, Faculty of Medical Sciences, University of Sri Jayewardenepura , Colombo , Sri Lanka
| | - Nisal Jayanetti
- Department of Parasitology, Faculty of Medical Sciences, University of Sri Jayewardenepura , Colombo , Sri Lanka
| | - Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya , Kelaniya , Sri Lanka
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Reis-Cunha JL, Baptista RP, Rodrigues-Luiz GF, Coqueiro-Dos-Santos A, Valdivia HO, de Almeida LV, Cardoso MS, D'Ávila DA, Dias FHC, Fujiwara RT, Galvão LMC, Chiari E, Cerqueira GC, Bartholomeu DC. Whole genome sequencing of Trypanosoma cruzi field isolates reveals extensive genomic variability and complex aneuploidy patterns within TcII DTU. BMC Genomics 2018; 19:816. [PMID: 30424726 PMCID: PMC6234542 DOI: 10.1186/s12864-018-5198-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 10/23/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI-TcVI. TcII is among the major DTUs enrolled in human infections in South America southern cone, where it is associated with severe cardiac and digestive symptoms. Despite the importance of TcII in Chagas disease epidemiology and pathology, so far, no genome-wide comparisons of the mitochondrial and nuclear genomes of TcII field isolates have been performed to track the variability and evolution of this DTU in endemic regions. RESULTS In the present work, we have sequenced and compared the whole nuclear and mitochondrial genomes of seven TcII strains isolated from chagasic patients from the central and northeastern regions of Minas Gerais, Brazil, revealing an extensive genetic variability within this DTU. A comparison of the phylogeny based on the nuclear or mitochondrial genomes revealed that the majority of branches were shared by both sequences. The subtle divergences in the branches are probably consequence of mitochondrial introgression events between TcII strains. Two T. cruzi strains isolated from patients living in the central region of Minas Gerais, S15 and S162a, were clustered in the nuclear and mitochondrial phylogeny analysis. These two strains were isolated from the other five by the Espinhaço Mountains, a geographic barrier that could have restricted the traffic of insect vectors during T. cruzi evolution in the Minas Gerais state. Finally, the presence of aneuploidies was evaluated, revealing that all seven TcII strains have a different pattern of chromosomal duplication/loss. CONCLUSIONS Analysis of genomic variability and aneuploidies suggests that there is significant genomic variability within Minas Gerais TcII strains, which could be exploited by the parasite to allow rapid selection of favorable phenotypes. Also, the aneuploidy patterns vary among T. cruzi strains and does not correlate with the nuclear phylogeny, suggesting that chromosomal duplication/loss are recent and frequent events in the parasite evolution.
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Affiliation(s)
- João Luís Reis-Cunha
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo P Baptista
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,The University of Georgia, Athens, USA
| | - Gabriela F Rodrigues-Luiz
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | | | - Hugo O Valdivia
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,U.S. Naval Medical Research, Lima, Peru
| | - Laila Viana de Almeida
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Mariana Santos Cardoso
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | | | | | - Lúcia M C Galvão
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Egler Chiari
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Daniella C Bartholomeu
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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25
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Almeida LV, Coqueiro-Dos-Santos A, Rodriguez-Luiz GF, McCulloch R, Bartholomeu DC, Reis-Cunha JL. Chromosomal copy number variation analysis by next generation sequencing confirms ploidy stability in Trypanosoma brucei subspecies. Microb Genom 2018; 4. [PMID: 30256189 PMCID: PMC6249438 DOI: 10.1099/mgen.0.000223] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Although aneuploidy usually results in severe abnormalities in multicellular eukaryotes, recent data suggest that it could be beneficial for unicellular eukaryotes, such as yeast and trypanosomatid parasites, providing increased survival under stressful conditions. Among characterized trypanosomatids, Trypanosoma cruzi, Trypanosoma brucei and species from the genus Leishmania stand out due to their importance in public health, infecting around 20 million people worldwide. The presence of aneuploidies in T. cruzi and Leishmania was recently confirmed by analysis based on next generation sequencing (NGS) and fluorescence in situ hybridization, where they have been associated with adaptation during transmission between their insect vectors and mammalian hosts and in promoting drug resistance. Although chromosomal copy number variations (CCNVs) are present in the aforementioned species, PFGE and fluorescence cytophotometry analyses suggest that aneuploidies are absent from T. brucei. A re-evaluation of CCNV in T. b gambiense based on NGS reads confirmed the absence of aneuploidies in this subspecies. However, the presence of aneuploidies in the other two T. brucei subspecies, T. b. brucei and T. b. rhodesiense, has not been evaluated using NGS approaches. In the present work, we tested for aneuploidies in 26 T. brucei isolates, including samples from the three T. brucei subspecies, by both allele frequency and read depth coverage analyses. These analyses showed that none of the T. brucei subspecies presents aneuploidies, which could be related to differences in the mechanisms of DNA replication and recombination in these parasites when compared with Leishmania.
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Affiliation(s)
- Laila Viana Almeida
- 1Departamento de Parasitologia, Universidade Federal de Minas Gerais - Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Anderson Coqueiro-Dos-Santos
- 1Departamento de Parasitologia, Universidade Federal de Minas Gerais - Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Gabriela F Rodriguez-Luiz
- 1Departamento de Parasitologia, Universidade Federal de Minas Gerais - Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Richard McCulloch
- 2University of Glasgow, Wellcome Centre for Molecular Parasitology, Glasgow, UK
| | - Daniella Castanheira Bartholomeu
- 1Departamento de Parasitologia, Universidade Federal de Minas Gerais - Instituto de Ciências Biológicas, Belo Horizonte, Brazil
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26
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Sienkiewicz N, Ong HB, Fairlamb AH. Characterisation of a putative glutamate 5-kinase from Leishmania donovani. FEBS J 2018; 285:2662-2678. [PMID: 29777624 PMCID: PMC6099280 DOI: 10.1111/febs.14511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/02/2018] [Accepted: 05/15/2018] [Indexed: 12/29/2022]
Abstract
Previous metabolic studies have demonstrated that leishmania parasites are able to synthesise proline from glutamic acid and threonine from aspartic acid. The first committed step in both biosynthetic pathways involves an amino acid kinase, either a glutamate 5‐kinase (G5K; http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/7/2/11.html) or an aspartokinase (http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/7/2/4.html). Bioinformatic analysis of multiple leishmania genomes identifies a single amino acid‐kinase gene (LdBPK 262740.1) variously annotated as either a putative glutamate or aspartate kinase. To establish the catalytic function of this Leishmania donovani gene product, we have determined the physical and kinetic properties of the recombinant enzyme purified from Escherichia coli. The findings indicate that the enzyme is a bona fide G5K with no activity as an aspartokinase. Tetrameric G5K displays kinetic behaviour similar to its bacterial orthologues and is allosterically regulated by proline, the end product of the pathway. The structure‐activity relationships of proline analogues as inhibitors are broadly similar to the bacterial enzyme. However, unlike G5K from E. coli, leishmania G5K lacks a C‐terminal PUA (pseudouridine synthase and archaeosine transglycosylase) domain and does not undergo higher oligomerisation in the presence of proline. Gene replacement studies are suggestive, but not conclusive that G5K is essential. Enzymes Glutamate 5‐kinase (http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/7/2/11.html); aspartokinase (http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/7/2/4.html).
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Affiliation(s)
- Natasha Sienkiewicz
- Division of Biological Chemistry & Drug Discovery, School of Life Sciences, University of Dundee, UK
| | - Han B Ong
- Division of Biological Chemistry & Drug Discovery, School of Life Sciences, University of Dundee, UK
| | - Alan H Fairlamb
- Division of Biological Chemistry & Drug Discovery, School of Life Sciences, University of Dundee, UK
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27
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Reis-Cunha JL, Valdivia HO, Bartholomeu DC. Gene and Chromosomal Copy Number Variations as an Adaptive Mechanism Towards a Parasitic Lifestyle in Trypanosomatids. Curr Genomics 2018; 19:87-97. [PMID: 29491737 PMCID: PMC5814966 DOI: 10.2174/1389202918666170911161311] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 03/14/2017] [Accepted: 04/18/2017] [Indexed: 12/21/2022] Open
Abstract
Trypanosomatids are a group of kinetoplastid parasites including some of great public health importance, causing debilitating and life-long lasting diseases that affect more than 24 million people worldwide. Among the trypanosomatids, Trypanosoma cruzi, Trypanosoma brucei and species from the Leishmania genus are the most well studied parasites, due to their high prevalence in human infections. These parasites have an extreme genomic and phenotypic variability, with a massive expansion in the copy number of species-specific multigene families enrolled in host-parasite interactions that mediate cellular invasion and immune evasion processes. As most trypanosomatids are heteroxenous, and therefore their lifecycles involve the transition between different hosts, these parasites have developed several strategies to ensure a rapid adaptation to changing environments. Among these strategies, a rapid shift in the repertoire of expressed genes, genetic variability and genome plasticity are key mechanisms. Trypanosomatid genomes are organized into large directional gene clusters that are transcribed polycistronically, where genes derived from the same polycistron may have very distinct mRNA levels. This particular mode of transcription implies that the control of gene expression operates mainly at post-transcriptional level. In this sense, gene duplications/losses were already associated with changes in mRNA levels in these parasites. Gene duplications also allow the generation of sequence variability, as the newly formed copy can diverge without loss of function of the original copy. Recently, aneuploidies have been shown to occur in several Leishmania species and T. cruzi strains. Although aneuploidies are usually associated with debilitating phenotypes in superior eukaryotes, recent data shows that it could also provide increased fitness in stress conditions and generate drug resistance in unicellular eukaryotes. In this review, we will focus on gene and chromosomal copy number variations and their relevance to the evolution of trypanosomatid parasites.
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Affiliation(s)
- João Luís Reis-Cunha
- Universidade Federal de Minas Gerais, Laboratório de Imunologia e Genômica de Parasitos, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
| | - Hugo O. Valdivia
- Universidade Federal de Minas Gerais, Laboratório de Imunologia e Genômica de Parasitos, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
- Centro de Investigaciones Tecnológicas, Biomédicas y Medioambientales, Callao, Peru
| | - Daniella Castanheira Bartholomeu
- Universidade Federal de Minas Gerais, Laboratório de Imunologia e Genômica de Parasitos, Instituto de Ciências Biológicas, Belo Horizonte, Brazil
- Centro de Investigaciones Tecnológicas, Biomédicas y Medioambientales, Callao, Peru
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28
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Abstract
Leishmania tropica, a unicellular eukaryotic parasite present in North and East Africa, the Middle East, and the Indian subcontinent, has been linked to large outbreaks of cutaneous leishmaniasis in displaced populations in Iraq, Jordan, and Syria. Here, we report the genome sequence of this pathogen and 7,863 identified protein-coding genes, and we show that the majority of clinical isolates possess high levels of allelic diversity, genetic admixture, heterozygosity, and extensive aneuploidy. By utilizing paired genome-wide high-throughput DNA sequencing (DNA-seq) with RNA-seq, we found that gene dosage, at the level of individual genes or chromosomal "somy" (a general term covering disomy, trisomy, tetrasomy, etc.), accounted for greater than 85% of total gene expression variation in genes with a 2-fold or greater change in expression. High gene copy number variation (CNV) among membrane-bound transporters, a class of proteins previously implicated in drug resistance, was found for the most highly differentially expressed genes. Our results suggest that gene dosage is an adaptive trait that confers phenotypic plasticity among natural Leishmania populations by rapid down- or upregulation of transporter proteins to limit the effects of environmental stresses, such as drug selection.IMPORTANCELeishmania is a genus of unicellular eukaryotic parasites that is responsible for a spectrum of human diseases that range from cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (MCL) to life-threatening visceral leishmaniasis (VL). Developmental and strain-specific gene expression is largely thought to be due to mRNA message stability or posttranscriptional regulatory networks for this species, whose genome is organized into polycistronic gene clusters in the absence of promoter-mediated regulation of transcription initiation of nuclear genes. Genetic hybridization has been demonstrated to yield dramatic structural genomic variation, but whether such changes in gene dosage impact gene expression has not been formally investigated. Here we show that the predominant mechanism determining transcript abundance differences (>85%) in Leishmania tropica is that of gene dosage at the level of individual genes or chromosomal somy.
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29
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Tihon E, Imamura H, Dujardin JC, Van Den Abbeele J, Van den Broeck F. Discovery and genomic analyses of hybridization between divergent lineages of Trypanosoma congolense, causative agent of Animal African Trypanosomiasis. Mol Ecol 2017; 26:6524-6538. [PMID: 28752916 DOI: 10.1111/mec.14271] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 05/24/2017] [Accepted: 06/28/2017] [Indexed: 12/19/2022]
Abstract
Hybrid populations and introgressive hybridization remain poorly documented in pathogenic micro-organisms, as such that genetic exchange has been argued to play a minor role in their evolution. Recent work demonstrated the existence of hybrid microsatellite profiles in Trypanosoma congolense, a parasitic protozoan with detrimental effects on livestock productivity in sub-Saharan Africa. Here, we present the first population genomic study of T. congolense, revealing a remarkable number of single nucleotide polymorphisms (SNPs), small insertions/deletions (indels) and gene deletions among 56 parasite genomes from ten African countries. One group of parasites from Zambia was particularly diverse, displaying a substantial number of heterozygous SNP and indel sites compared to T. congolense parasites from the nine other sub-Saharan countries. Genomewide 5-kb phylogenetic analyses based on phased SNP data revealed that these parasites were the product of hybridization between phylogenetically distinct T. congolense lineages. Other parasites within the same region in Zambia presented a mosaic of haplotypic ancestry and genetic variability, indicating that hybrid parasites persisted and recombined beyond the initial hybridization event. Our observations challenge traditional views of trypanosome population biology and encourage future research on the role of hybridization in spreading genes for drug resistance, pathogenicity and virulence.
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Affiliation(s)
- Eliane Tihon
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Hideo Imamura
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Jean-Claude Dujardin
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Jan Van Den Abbeele
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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Fluconazole-Induced Ploidy Change in Cryptococcus neoformans Results from the Uncoupling of Cell Growth and Nuclear Division. mSphere 2017. [PMID: 28630940 PMCID: PMC5471349 DOI: 10.1128/msphere.00205-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Azoles are antifungals that are widely utilized due to relatively low toxicity and cost of treatment. One of their drawbacks, however, is that azoles are primarily cytostatic, leaving fungal cells capable of developing drug resistance. The human pathogen Cryptococcus neoformans acquires resistance to the azole drug fluconazole (FLC) through the development of aneuploidy, leading to elevated expression of key resistance genes, a mechanism that is also common for Candida albicans (K. J. Kwon-Chung and Y. C. Chang, PLoS Pathog 8:e1003022, 2012, https://doi.org/10.1371/journal.ppat.1003022; J. Morschhäuser, J Microbiol 54:192–201, 2016, https://doi.org/10.1007/s12275-016-5628-4). However, the exact ways in which FLC contributes to increased resistance in either of these important fungal pathogens remain unclear. Here we found that FLC treatment leads to an increase in DNA content in C. neoformans through multiple mechanisms, potentially increasing the size of a pool of cells from which aneuploids with increased resistance are selected. This study demonstrated the importance of FLC’s inhibitory effects on growth and cytokinesis in the generation of cell populations with decreased sensitivity to the drug. Cryptococcus neoformans is a pathogenic yeast that causes lethal cryptococcal meningitis in immunocompromised patients. One of the challenges in treating cryptococcosis is the development of resistance to azole antifungals. Previous studies linked azole resistance to elevated numbers of copies of critical resistance genes in aneuploid cells. However, how aneuploidy is formed in the presence of azole drugs remains unclear. This study showed that treatment with inhibitory concentrations of an azole drug, fluconazole (FLC), resulted in a significant population of cells with increased DNA content, through the following defects: inhibition of budding, premature mitosis, and inhibition of cytokinesis followed by replication in the mother cell. Inhibition of and/or a delay in cytokinesis led to the formation of cells with two or more daughter cells attached (multimeric cells). To investigate which part of cytokinesis fails in the presence of FLC, the dynamics of the actomyosin ring (AMR), septins, and Cts1, a protein involved in cell separation, were analyzed with time-lapse microscopy. Following the constriction of the AMR, septins assembled and the septum was formed between the mother and daughter cells. However, final degradation of the septum was affected. Enlarged cells with aberrant morphology, including multimeric cells, exhibited an increased potential to proliferate in the presence of FLC. These findings suggest that pleiotropic effects of FLC on growth and mitotic division lead to an increase in DNA content, resulting in cells less sensitive to the drug. Cells with increased DNA content continue to proliferate and therefore increase the chance of forming resistant populations. IMPORTANCE Azoles are antifungals that are widely utilized due to relatively low toxicity and cost of treatment. One of their drawbacks, however, is that azoles are primarily cytostatic, leaving fungal cells capable of developing drug resistance. The human pathogen Cryptococcus neoformans acquires resistance to the azole drug fluconazole (FLC) through the development of aneuploidy, leading to elevated expression of key resistance genes, a mechanism that is also common for Candida albicans (K. J. Kwon-Chung and Y. C. Chang, PLoS Pathog 8:e1003022, 2012, https://doi.org/10.1371/journal.ppat.1003022; J. Morschhäuser, J Microbiol 54:192–201, 2016, https://doi.org/10.1007/s12275-016-5628-4). However, the exact ways in which FLC contributes to increased resistance in either of these important fungal pathogens remain unclear. Here we found that FLC treatment leads to an increase in DNA content in C. neoformans through multiple mechanisms, potentially increasing the size of a pool of cells from which aneuploids with increased resistance are selected. This study demonstrated the importance of FLC’s inhibitory effects on growth and cytokinesis in the generation of cell populations with decreased sensitivity to the drug.
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31
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Rougeron V, De Meeûs T, Bañuls AL. Reproduction in Leishmania: A focus on genetic exchange. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2017; 50:128-132. [PMID: 27769896 DOI: 10.1016/j.meegid.2016.10.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 10/17/2016] [Accepted: 10/18/2016] [Indexed: 11/26/2022]
Abstract
One key process of the life cycle of pathogens is their mode of reproduction. Indeed, this fundamental biological process conditions the multiplication and the transmission of genes and thus the propagation of diseases in the environment. Reproductive strategies of protozoan parasites have been a subject of debate for many years, principally due to the difficulty in making direct observations of sexual reproduction (i.e. genetic recombination). Traditionally, these parasites were considered as characterized by a preeminent clonal structure. Nevertheless, with the development of elaborate culture experiments, population genetics and evolutionary and population genomics, several studies suggested that most of these pathogens were also characterized by constitutive genetic recombination events. In this opinion, we focused on Leishmania parasites, pathogens responsible of leishmaniases, a major public health issue. We first discuss the evolutionary advantages of a mixed mating reproductive strategy, then we review the evidence of genetic exchange, and finally we detail available tools to detect naturally occurring genetic recombination in Leishmania parasites and more generally in protozoan parasites.
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Affiliation(s)
- V Rougeron
- MIVEGEC (Laboratoire Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle), UMR CNRS 5290-IRD 224-Université de Montpellier, Montpellier, France.
| | - T De Meeûs
- Institut de Recherche pour le Développement (IRD), UMR 177 INTERTRYP IRD-CIRAD, TA A-17/G, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France
| | - A-L Bañuls
- MIVEGEC (Laboratoire Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle), UMR CNRS 5290-IRD 224-Université de Montpellier, Montpellier, France
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Espiau B, Vilhena V, Cuvillier A, Barral A, Merlin G. Phenotypic diversity and selection maintain Leishmania amazonensis infectivity in BALB/c mouse model. Mem Inst Oswaldo Cruz 2017; 112:44-52. [PMID: 28076468 PMCID: PMC5225529 DOI: 10.1590/0074-02760160280] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/14/2016] [Indexed: 11/21/2022] Open
Abstract
Leishmania are protozoan parasites that show remarkable diversity, as revealed by the various clinical forms of leishmaniasis, which can range from mild skin lesions to severe metastatic cutaneous/mucosal lesions. The exact nature and extent of Leishmania phenotypic diversity in establishing infection is not fully understood. In order to try to understand some aspects of this diversity, we subcutaneously infected BALB/c mice with first and second generation subclones of a L. amazonensis strain isolated from a patient (BA125) and examined in vivo lesion growth rate and antimony susceptibility. In vivo fast-, medium- and slow-growing subclones were obtained; moreover, fast-growing subclones could generate slow-growing subclones and inversely, revealing the continuous generation of diversity after passage into mice. No antimony-resistant subclone appeared, probably a rare occurrence. By tagging subclone cells with a L. amazonensis genomic cosmid library, we found that only a very small number of founding cells could produce lesions. Leishmania clones transfected with in vivo selected individual cosmids were also diverse in terms of lesion growth rate, revealing the cosmid-independent intrinsic characteristics of each clone. Our results suggest that only a few of the infecting parasites are able to grow and produce lesions; later, within the cell mixture of each lesion, there coexist several parasite populations with different potentialities to grow lesions during the next infection round. This may reflect a sort of programmed heterogeneity of individual parasites, favoring the survival of some individuals in various environmental conditions.
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Affiliation(s)
- Benoît Espiau
- Université de Bordeaux, Laboratoire de Génomique Fonctionnelle des Trypanosomatidés, Bordeaux, France.,LabEx Corail, Papetoai, Moorea, Polynésie Française
| | - Virginia Vilhena
- Fundação Oswaldo Cruz, Instituto Gonçalo Moniz, Salvador, BA, Brasil.,Faculdade Anhanguera de Brasília, Brasília, DF, Brasil
| | - Armelle Cuvillier
- Université de Bordeaux, Laboratoire de Génomique Fonctionnelle des Trypanosomatidés, Bordeaux, France.,B Cell Design, Limoges, France
| | - Aldina Barral
- Fundação Oswaldo Cruz, Instituto Gonçalo Moniz, Salvador, BA, Brasil.,Instituto de Investigação em Imunologia, Salvador, BA, Brasil
| | - Gilles Merlin
- Université de Bordeaux, Laboratoire de Génomique Fonctionnelle des Trypanosomatidés, Bordeaux, France.,Instituto de Investigação em Imunologia, Salvador, BA, Brasil
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33
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Tibayrenc M, Ayala FJ. Is Predominant Clonal Evolution a Common Evolutionary Adaptation to Parasitism in Pathogenic Parasitic Protozoa, Fungi, Bacteria, and Viruses? ADVANCES IN PARASITOLOGY 2016; 97:243-325. [PMID: 28325372 DOI: 10.1016/bs.apar.2016.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We propose that predominant clonal evolution (PCE) in microbial pathogens be defined as restrained recombination on an evolutionary scale, with genetic exchange scarce enough to not break the prevalent pattern of clonal population structure. The main features of PCE are (1) strong linkage disequilibrium, (2) the widespread occurrence of stable genetic clusters blurred by occasional bouts of genetic exchange ('near-clades'), (3) the existence of a "clonality threshold", beyond which recombination is efficiently countered by PCE, and near-clades irreversibly diverge. We hypothesize that the PCE features are not mainly due to natural selection but also chiefly originate from in-built genetic properties of pathogens. We show that the PCE model obtains even in microbes that have been considered as 'highly recombining', such as Neisseria meningitidis, and that some clonality features are observed even in Plasmodium, which has been long described as panmictic. Lastly, we provide evidence that PCE features are also observed in viruses, taking into account their extremely fast genetic turnover. The PCE model provides a convenient population genetic framework for any kind of micropathogen. It makes it possible to describe convenient units of analysis (clones and near-clades) for all applied studies. Due to PCE features, these units of analysis are stable in space and time, and clearly delimited. The PCE model opens up the possibility of revisiting the problem of species definition in these organisms. We hypothesize that PCE constitutes a major evolutionary strategy for protozoa, fungi, bacteria, and viruses to adapt to parasitism.
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Affiliation(s)
- M Tibayrenc
- Institut de Recherche pour le Développement, Montpellier, France
| | - F J Ayala
- University of California at Irvine, United States
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Laffitte MCN, Leprohon P, Papadopoulou B, Ouellette M. Plasticity of the Leishmania genome leading to gene copy number variations and drug resistance. F1000Res 2016; 5:2350. [PMID: 27703673 PMCID: PMC5031125 DOI: 10.12688/f1000research.9218.1] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/19/2016] [Indexed: 01/04/2023] Open
Abstract
Leishmania has a plastic genome, and drug pressure can select for gene copy number variation (CNV). CNVs can apply either to whole chromosomes, leading to aneuploidy, or to specific genomic regions. For the latter, the amplification of chromosomal regions occurs at the level of homologous direct or inverted repeated sequences leading to extrachromosomal circular or linear amplified DNAs. This ability of
Leishmania to respond to drug pressure by CNVs has led to the development of genomic screens such as Cos-Seq, which has the potential of expediting the discovery of drug targets for novel promising drug candidates.
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Affiliation(s)
- Marie-Claude N Laffitte
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec, and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec, and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Barbara Papadopoulou
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec, and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec, and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
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Bifeld E, Tejera Nevado P, Bartsch J, Eick J, Clos J. A versatile qPCR assay to quantify trypanosomatidic infections of host cells and tissues. Med Microbiol Immunol 2016; 205:449-58. [PMID: 27283847 DOI: 10.1007/s00430-016-0460-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/27/2016] [Indexed: 02/06/2023]
Abstract
The majority of PCR-based detection systems for Leishmania spp. and Trypanosoma cruzi aim at high sensitivity and specificity, rather than an accurate parasite load quantification required for experimental infections in basic research and drug development. Here, we describe the use of a dual-labelled probe qPCR to detect and quantify intracellular Old World Leishmania spp. and T. cruzi amastigotes after in vitro and in vivo infection experiments. We show that quantification of parasite actin gene DNA relative to the host cell actin gene DNA accurately reflects the parasite load relative to the host cells and that qPCR quantification is highly sensible to drug-induced cell death. Furthermore, qPCR allows to determine parasite loads even after host cell detachment and/or rupture, important when comparing untreated versus drug-treated samples. The method is also suitable for the quantification of parasites from infected mouse tissue, making it suitable for drug testing and mutant phenotype analysis.
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Affiliation(s)
- Eugenia Bifeld
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany
| | - Paloma Tejera Nevado
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany
| | - Janika Bartsch
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany.,Beuth Hochschule für Technik, Berlin, Germany
| | - Julia Eick
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany
| | - Joachim Clos
- Bernhard Nocht Institute for Tropical Medicine, Bernhard Nocht St 74, 20359, Hamburg, Germany.
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Stanojcic S, Sollelis L, Kuk N, Crobu L, Balard Y, Schwob E, Bastien P, Pagès M, Sterkers Y. Single-molecule analysis of DNA replication reveals novel features in the divergent eukaryotes Leishmania and Trypanosoma brucei versus mammalian cells. Sci Rep 2016; 6:23142. [PMID: 26976742 PMCID: PMC4791591 DOI: 10.1038/srep23142] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 02/17/2016] [Indexed: 01/29/2023] Open
Abstract
Leishmania and Trypanosoma are unicellular parasites that possess markedly original biological features as compared to other eukaryotes. The Leishmania genome displays a constitutive 'mosaic aneuploidy', whereas in Trypanosoma brucei, the megabase-sized chromosomes are diploid. We accurately analysed DNA replication parameters in three Leishmania species and Trypanosoma brucei as well as mouse embryonic fibroblasts (MEF). Active replication origins were visualized at the single molecule level using DNA molecular combing. More than one active origin was found on most DNA fibres, showing that the chromosomes are replicated from multiple origins. Inter-origin distances (IODs) were measured and found very large in trypanosomatids: the mean IOD was 160 kb in T. brucei and 226 kb in L. mexicana. Moreover, the progression of replication forks was faster than in any other eukaryote analyzed so far (mean velocity 1.9 kb/min in T. brucei and 2.4-2.6 kb/min in Leishmania). The estimated total number of active DNA replication origins in trypanosomatids is ~170. Finally, 14.4% of unidirectional replication forks were observed in T. brucei, in contrast to 1.5-1.7% in Leishmania and 4% in MEF cells. The biological significance of these original features is discussed.
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Affiliation(s)
- Slavica Stanojcic
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France
| | - Lauriane Sollelis
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France
| | - Nada Kuk
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France
| | - Lucien Crobu
- CNRS 5290 - IRD 224 - University of Montpellier (UMR "MiVEGEC"), Montpellier, F34090, France
| | - Yves Balard
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France
| | - Etienne Schwob
- Institute of Molecular Genetics, CNRS UMR5535 &University of Montpellier, Montpellier, F34293, France
| | - Patrick Bastien
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France.,CNRS 5290 - IRD 224 - University of Montpellier (UMR "MiVEGEC"), Montpellier, F34090, France.,University Hospital Centre (CHU), Department of Parasitology-Mycology, Montpellier, F34090, France
| | - Michel Pagès
- CNRS 5290 - IRD 224 - University of Montpellier (UMR "MiVEGEC"), Montpellier, F34090, France
| | - Yvon Sterkers
- University of Montpellier, Faculty of Medicine, Laboratory of Parasitology-Mycology, Montpellier, F34090, France.,CNRS 5290 - IRD 224 - University of Montpellier (UMR "MiVEGEC"), Montpellier, F34090, France.,University Hospital Centre (CHU), Department of Parasitology-Mycology, Montpellier, F34090, France
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Alcolea PJ, Alonso A, Moreno-Izquierdo MA, Degayón MA, Moreno I, Larraga V. Serum Removal from Culture Induces Growth Arrest, Ploidy Alteration, Decrease in Infectivity and Differential Expression of Crucial Genes in Leishmania infantum Promastigotes. PLoS One 2016; 11:e0150172. [PMID: 26959417 PMCID: PMC4784933 DOI: 10.1371/journal.pone.0150172] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 02/10/2016] [Indexed: 11/19/2022] Open
Abstract
Leishmania infantum is one of the species responsible for visceral leishmaniasis. This species is distributed basically in the Mediterranean basin. A recent outbreak in humans has been reported in Spain. Axenic cultures are performed for most procedures with Leishmania spp. promastigotes. This model is stable and reproducible and mimics the conditions of the gut of the sand fly host, which is the natural environment of promastigote development. Culture media are undefined because they contain mammalian serum, which is a rich source of complex lipids and proteins. Serum deprivation slows down the growth kinetics and therefore, yield in biomass. In fact, we have confirmed that the growth rate decreases, as well as infectivity. Ploidy is also affected. Regarding the transcriptome, a high-throughput approach has revealed a low differential expression rate but important differentially regulated genes. The most remarkable profiles are: up-regulation of the GINS Psf3, the fatty acyl-CoA synthase (FAS1), the glyoxylase I (GLO1), the hydrophilic surface protein B (HASPB), the methylmalonyl-CoA epimerase (MMCE) and an amastin gene; and down-regulation of the gPEPCK and the arginase. Implications for metabolic adaptations, differentiation and infectivity are discussed herein.
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Affiliation(s)
- Pedro J. Alcolea
- Department of Molecular Microbiology and Biology of Infections, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid. Spain
- * E-mail:
| | - Ana Alonso
- Department of Molecular Microbiology and Biology of Infections, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid. Spain
| | - Miguel A. Moreno-Izquierdo
- Department of Molecular Microbiology and Biology of Infections, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid. Spain
| | - María A. Degayón
- Department of Molecular Microbiology and Biology of Infections, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid. Spain
| | - Inmaculada Moreno
- Unit of Microbial Immunology, Centro Nacional de Microbiología, Virología e Inmunología Sanitarias, Instituto de Salud Carlos III (CNM-ISCIII), Majadahonda, Spain
| | - Vicente Larraga
- Department of Molecular Microbiology and Biology of Infections, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), Madrid. Spain
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Berman J. Ploidy plasticity: a rapid and reversible strategy for adaptation to stress. FEMS Yeast Res 2016; 16:fow020. [PMID: 26945893 DOI: 10.1093/femsyr/fow020] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2016] [Indexed: 12/22/2022] Open
Abstract
Organisms must be able to grow in a broad range of conditions found in their normal growth environment and for a species to survive, at least some cells in a population must adapt rapidly to extreme stress conditions that kill the majority of cells.Candida albicans, the most prevalent fungal pathogen of humans resides as a commensal in a broad range of niches within the human host. Growth conditions in these niches are highly variable and stresses such exposure to antifungal drugs can inhibit population growth abruptly. One of the mechanisms C. albicans uses to adapt rapidly to severe stresses is aneuploidy-a change in the total number of chromosomes such that one or more chromosomes are present in excess or are missing. Aneuploidy is quite common in wild isolates of fungi and other eukaryotic microbes. Aneuploidy can be achieved by chromosome nondisjunction during a simple mitosis, and in stress conditions it begins to appear after two mitotic divisions via a tetraploid intermediate. Aneuploidy usually resolves to euploidy (a balanced number of chromosomes), but not necessarily to diploidy. Aneuploidy of a specific chromosome can confer new phenotypes by virtue of the copy number of specific genes on that chromosome relative to the copies of other genes. Thus, it is not aneuploidy per se, but the relative copy number of specific genes that confers many tested aneuploidy-associated phenotypes. Aneuploidy almost always carries a fitness cost, as cells express most proteins encoded by genes on the aneuploid chromosome in proportion to the number of DNA copies of the gene. This is thought to be due to imbalances in the stoichiometry of different components of large complexes. Despite this, fitness is a relative function-and if stress is severe and population growth has slowed considerably, then even small growth advantages of some aneuploidies can provide a selective advantage. Thus, aneuploidy appears to provide a transient solution to severe and sudden stress conditions, and may promote the appearance of more stable solutions as well. Importantly, in many clinical and environmental isolates of different fungal species aneuploidy does not appear to have a high fitness cost, and is well-tolerated. Thus, rapid changes in ploidy may provide the opportunity for rapid adaptation to stress conditions in the environment, host niches or in response to antifungal drugs.
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Affiliation(s)
- Judith Berman
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv, 69978 Tel Aviv, Israel
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Tibayrenc M, Ayala FJ. The population genetics of Trypanosoma cruzi revisited in the light of the predominant clonal evolution model. Acta Trop 2015; 151:156-65. [PMID: 26188332 PMCID: PMC7117470 DOI: 10.1016/j.actatropica.2015.05.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/02/2015] [Accepted: 05/06/2015] [Indexed: 01/18/2023]
Abstract
Comparing the population structure of Trypanosoma cruzi with that of other pathogens, including parasitic protozoa, fungi, bacteria and viruses, shows that the agent of Chagas disease shares typical traits with many other species, related to a predominant clonal evolution (PCE) pattern: statistically significant linkage disequilibrium, overrepresented multilocus genotypes, near-clades (genetic subdivisions somewhat blurred by occasional genetic exchange/hybridization) and "Russian doll" patterns (PCE is observed, not only at the level of the whole species, but also, within the near-clades). Moreover, T. cruzi population structure exhibits linkage with the diversity of several strongly selected genes, with gene expression profiles, and with some major phenotypic traits. We discuss the evolutionary significance of these results, and their implications in terms of applied research (molecular epidemiology/strain typing, analysis of genes of interest, vaccine and drug design, immunological diagnosis) and of experimental evolution. Lastly, we revisit the long-term debate of describing new species within the T. cruzi taxon.
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Neglected Tropical Diseases in the Post-Genomic Era. Trends Genet 2015; 31:539-555. [DOI: 10.1016/j.tig.2015.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/01/2015] [Accepted: 06/03/2015] [Indexed: 01/22/2023]
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Plourde M, Ubeda JM, Mandal G, Monte-Neto RLD, Mukhopadhyay R, Ouellette M. Generation of an aquaglyceroporin AQP1 null mutant in Leishmania major. Mol Biochem Parasitol 2015. [PMID: 26222914 DOI: 10.1016/j.molbiopara.2015.07.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The Leishmania aquaglyceroporin AQP1 plays an important physiological role in water and uncharged polar solutes transport, volume regulation, osmotaxis, and is a key determinant of antimony resistance. By targeted gene disruption, we generated a Leishmania major promastigote AQP1 null mutant. This required several attempts but a chromosomal null AQP1 mutant was obtained by loss of heterozygosity in the presence of a rescue plasmid encoding AQP1. Growth in the absence of selection led to the loss of the rescuing plasmid, indicating that AQP1 is not essential for Leishmania viability. The AQP1-null mutant was resistant to antimonyl tartrate (SbIII) and arsenite (AsIII) due to a decrease import of these metalloids. It also exhibited alterations in its osmoregulation abilities compared with wild-type cells. This is the first report of the generation of a genetic AQP1 null mutant in Leishmania parasite, confirming its physiological function and role in resistance to antimonials, the therapeutic mainstay against Leishmania.
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Affiliation(s)
- Marie Plourde
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU and Département de Microbiologie, Immunologie et Infectiologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Jean-Michel Ubeda
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU and Département de Microbiologie, Immunologie et Infectiologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Goutam Mandal
- Molecular Microbiology and Infectious Diseases, Herbert Wertheim College of Medicine, Miami, USA
| | | | - Rita Mukhopadhyay
- Molecular Microbiology and Infectious Diseases, Herbert Wertheim College of Medicine, Miami, USA
| | - Marc Ouellette
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU and Département de Microbiologie, Immunologie et Infectiologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada.
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Response to Rougeron et al.: Leishmania population genetics: clonality, selfing and aneuploidy. Trends Parasitol 2015; 31:279-80. [DOI: 10.1016/j.pt.2015.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 03/31/2015] [Accepted: 04/02/2015] [Indexed: 11/18/2022]
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Sollelis L, Ghorbal M, MacPherson CR, Martins RM, Kuk N, Crobu L, Bastien P, Scherf A, Lopez-Rubio JJ, Sterkers Y. First efficient CRISPR-Cas9-mediated genome editing inLeishmaniaparasites. Cell Microbiol 2015; 17:1405-12. [DOI: 10.1111/cmi.12456] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 04/24/2015] [Accepted: 04/27/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Lauriane Sollelis
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
| | - Mehdi Ghorbal
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
| | - Cameron Ross MacPherson
- Institut Pasteur - INSERM U1201 - CNRS ERL9195; “Biology of Host-Parasite Interactions” Unit; Paris France
| | - Rafael Miyazawa Martins
- Institut Pasteur - INSERM U1201 - CNRS ERL9195; “Biology of Host-Parasite Interactions” Unit; Paris France
| | - Nada Kuk
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
| | - Lucien Crobu
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
| | - Patrick Bastien
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
- CHRU (Centre Hospitalier Universitaire de Montpellier); Department of Parasitology-Mycology; Montpellier France
| | - Artur Scherf
- Institut Pasteur - INSERM U1201 - CNRS ERL9195; “Biology of Host-Parasite Interactions” Unit; Paris France
| | - Jose-Juan Lopez-Rubio
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
| | - Yvon Sterkers
- University of Montpellier; Faculty of Medicine; Laboratory of Parasitology-Mycology; Paris France
- CNRS - 5290; IRD 224 - University of Montpellier (UMR ‘MiVEGEC’); Paris France
- CHRU (Centre Hospitalier Universitaire de Montpellier); Department of Parasitology-Mycology; Montpellier France
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Monte-Neto R, Laffitte MCN, Leprohon P, Reis P, Frézard F, Ouellette M. Intrachromosomal amplification, locus deletion and point mutation in the aquaglyceroporin AQP1 gene in antimony resistant Leishmania (Viannia) guyanensis. PLoS Negl Trop Dis 2015; 9:e0003476. [PMID: 25679388 PMCID: PMC4332685 DOI: 10.1371/journal.pntd.0003476] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/14/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Antimony resistance complicates the treatment of infections caused by the parasite Leishmania. METHODOLOGY/PRINCIPAL FINDINGS Using next generation sequencing, we sequenced the genome of four independent Leishmania guyanensis antimony-resistant (SbR) mutants and found different chromosomal alterations including aneuploidy, intrachromosomal gene amplification and gene deletion. A segment covering 30 genes on chromosome 19 was amplified intrachromosomally in three of the four mutants. The gene coding for the multidrug resistance associated protein A involved in antimony resistance was also amplified in the four mutants, most likely through chromosomal translocation. All mutants also displayed a reduced accumulation of antimony mainly due to genomic alterations at the level of the subtelomeric region of chromosome 31 harboring the gene coding for the aquaglyceroporin 1 (LgAQP1). Resistance involved the loss of LgAQP1 through subtelomeric deletions in three mutants. Interestingly, the fourth mutant harbored a single G133D point mutation in LgAQP1 whose role in resistance was functionality confirmed through drug sensitivity and antimony accumulation assays. In contrast to the Leishmania subspecies that resort to extrachromosomal amplification, the Viannia strains studied here used intrachromosomal amplification and locus deletion. CONCLUSIONS/SIGNIFICANCE This is the first report of a naturally occurred point mutation in AQP1 in antimony resistant parasites.
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Affiliation(s)
- Rubens Monte-Neto
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Marie-Claude N. Laffitte
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
| | - Priscila Reis
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Frédéric Frézard
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brasil
| | - Marc Ouellette
- Centre de Recherche en Infectiologie du Centre de Recherche du CHU Québec and Département de Microbiologie, Infectiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada
- * E-mail:
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Cross-species genetic exchange between visceral and cutaneous strains of Leishmania in the sand fly vector. Proc Natl Acad Sci U S A 2014; 111:16808-13. [PMID: 25385616 DOI: 10.1073/pnas.1415109111] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Genetic exchange between Leishmania major strains during their development in the sand fly vector has been experimentally shown. To investigate the possibility of genetic exchange between different Leishmania species, a cutaneous strain of L. major and a visceral strain of Leishmania infantum, each bearing a different drug-resistant marker, were used to coinfect Lutzomyia longipalpis sand flies. Eleven double-drug-resistant progeny clones, each the product of an independent mating event, were generated and submitted to genotype and phenotype analyses. The analysis of multiple allelic markers across the genome suggested that each progeny clone inherited at least one full set of chromosomes from each parent, with loss of heterozygosity at some loci, and uniparental retention of maxicircle kinetoplast DNA. Hybrids with DNA contents of approximately 2n, 3n, and 4n were observed. In vivo studies revealed clear differences in the ability of the hybrids to produce pathology in the skin or to disseminate to and grow in the viscera, suggesting polymorphisms and differential inheritance of the gene(s) controlling these traits. The studies, to our knowledge, represent the first experimental confirmation of cross-species mating in Leishmania, opening the way toward genetic linkage analysis of important traits and providing strong evidence that genetic exchange is responsible for the generation of the mixed-species genotypes observed in natural populations.
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Leprohon P, Fernandez-Prada C, Gazanion É, Monte-Neto R, Ouellette M. Drug resistance analysis by next generation sequencing in Leishmania. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2014; 5:26-35. [PMID: 25941624 PMCID: PMC4412915 DOI: 10.1016/j.ijpddr.2014.09.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/04/2014] [Accepted: 09/08/2014] [Indexed: 12/30/2022]
Abstract
WGS revealed the complexity of resistance which is often polyclonal in Leishmania. An impressive variation in chromosome copy numbers exist between Leishmania species. The genotype heterogeneity complicates the analysis of resistance in field isolates.
The use of next generation sequencing has the power to expedite the identification of drug resistance determinants and biomarkers and was applied successfully to drug resistance studies in Leishmania. This allowed the identification of modulation in gene expression, gene dosage alterations, changes in chromosome copy numbers and single nucleotide polymorphisms that correlated with resistance in Leishmania strains derived from the laboratory and from the field. An impressive heterogeneity at the population level was also observed, individual clones within populations often differing in both genotypes and phenotypes, hence complicating the elucidation of resistance mechanisms. This review summarizes the most recent highlights that whole genome sequencing brought to our understanding of Leishmania drug resistance and likely new directions.
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Affiliation(s)
- Philippe Leprohon
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Christopher Fernandez-Prada
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Élodie Gazanion
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Rubens Monte-Neto
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec, 2705 Laurier Blvd., Québec G1V 4G2, Canada
| | - Marc Ouellette
- Centre de Recherche en Infectiologie, Centre de Recherche du CHU de Québec, 2705 Laurier Blvd., Québec G1V 4G2, Canada
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Parasexuality and mosaic aneuploidy in Leishmania: alternative genetics. Trends Parasitol 2014; 30:429-35. [PMID: 25073852 DOI: 10.1016/j.pt.2014.07.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/04/2014] [Accepted: 07/07/2014] [Indexed: 12/25/2022]
Abstract
Reproduction as identical or similar organisms in most biological systems depends on the extreme accuracy of the mitotic (and meiotic) mechanisms involved in the transmission of the genetic material to the two daughter cells. Character recombination and genotype diversification are ensured by the alternation between haploidy and diploidy, which corresponds to the most predominant model in sexually reproducing organisms. In Leishmania, the unique association of high levels of automixis and of constitutive 'mosaic aneuploidy' unexpectedly does not lead to loss of heterozygosity but constitutes an alternative for genotype recombination, hence a source of adaptability.
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Sterkers Y, Walton EL. The Leishmania chromosome lottery. Microbes Infect 2013; 16:2-5. [PMID: 24286926 DOI: 10.1016/j.micinf.2013.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 11/18/2013] [Indexed: 11/27/2022]
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