scholarly journals Generation of Transgenic Human Malaria Parasites With Strong Fluorescence in the Transmission Stages

2018 ◽  
Author(s):  
Kyle J McLean ◽  
Judith Straimer ◽  
Christine S Hopp ◽  
Joel Vega-Rodriguez ◽  
Abhai Tripathi ◽  
...  
Keyword(s):  
Life Cycle ◽  
Integration Site ◽  
Complex Life Cycle ◽  
Phenotypic Characterization ◽  
Malaria Parasites ◽  
Genome Expression ◽  
High Infection ◽  
Parasite Plasmodium ◽  
Parasite Plasmodium Falciparum ◽  
Marker Free

Malaria parasites have a complex life cycle that includes specialized stages for transmission between their mosquito and human hosts. These stages are an understudied part of the lifecycle yet targeting them is an essential component of the effort to shrink the malaria map. The human parasite Plasmodium falciparum is responsible for the majority of deaths due to malaria. Our goal was to generate transgenic P. falciparum lines that could complete the lifecycle and produce fluorescent transmission stages for more in-depth and high-throughput studies. Using zinc-finger nuclease technology to engineer a marker-free integration site, we generated three transgenic P. falciparum lines in which tdtomato or gfp were stably integrated into the genome. Expression was driven by either stage-specific peg4 and csp promoters or the constitutive ef1a promoter. Phenotypic characterization of these lines demonstrates that they complete the life cycle with high infection rates and give rise to fluorescent mosquito stages. The transmission stages are sufficiently bright for intra-vital imaging, flow cytometry and scalable screening of chemical inhibitors and potentially inhibitory antibodies.

scholarly journals Generation of Transmission-Competent Human Malaria Parasites with Chromosomally-Integrated Fluorescent Reporters

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kyle Jarrod McLean ◽  
Judith Straimer ◽  
Christine S. Hopp ◽  
Joel Vega-Rodriguez ◽  
Jennifer L. Small-Saunders ◽  
...  
Keyword(s):  
Life Cycle ◽  
Integration Site ◽  
Complex Life Cycle ◽  
Phenotypic Characterization ◽  
Malaria Parasites ◽  
Fluorescent Reporters ◽  
Genome Expression ◽  
Chemical Inhibitors ◽  
High Infection

Abstract Malaria parasites have a complex life cycle that includes specialized stages for transmission between their mosquito and human hosts. These stages are an understudied part of the lifecycle yet targeting them is an essential component of the effort to shrink the malaria map. The human parasite Plasmodium falciparum is responsible for the majority of deaths due to malaria. Our goal was to generate transgenic P. falciparum lines that could complete the lifecycle and produce fluorescent transmission stages for more in-depth and high-throughput studies. Using zinc-finger nuclease technology to engineer an integration site, we generated three transgenic P. falciparum lines in which tdtomato or gfp were stably integrated into the genome. Expression was driven by either stage-specific peg4 and csp promoters or the constitutive ef1a promoter. Phenotypic characterization of these lines demonstrates that they complete the life cycle with high infection rates and give rise to fluorescent mosquito stages. The transmission stages are sufficiently bright for intra-vital imaging, flow cytometry and scalable screening of chemical inhibitors and inhibitory antibodies.

scholarly journals Mitosis in the Human Malaria Parasite Plasmodium falciparum

2011 ◽  
Vol 10 (4) ◽  
pp. 474-482 ◽  
Author(s):  
Noel Gerald ◽  
Babita Mahajan ◽  
Sanjai Kumar
Keyword(s):  
Plasmodium Falciparum ◽  
Life Cycle ◽  
Complex Life Cycle ◽  
Anopheline Mosquito ◽  
Essential Requirement ◽  
Human Malaria Parasite ◽  
Content Type ◽  
Parasite Plasmodium ◽  
Parasite Plasmodium Falciparum ◽  
Key Events

ABSTRACT Malaria is caused by intraerythrocytic protozoan parasites belonging to Plasmodium spp. (phylum Apicomplexa ) that produce significant morbidity and mortality, mostly in developing countries. Plasmodium parasites have a complex life cycle that includes multiple stages in anopheline mosquito vectors and vertebrate hosts. During the life cycle, the parasites undergo several cycles of extreme population growth within a brief span, and this is critical for their continued transmission and a contributing factor for their pathogenesis in the host. As with other eukaryotes, successful mitosis is an essential requirement for Plasmodium reproduction; however, some aspects of Plasmodium mitosis are quite distinct and not fully understood. In this review, we will discuss the current understanding of the architecture and key events of mitosis in Plasmodium falciparum and related parasites and compare them with the traditional mitotic events described for other eukaryotes.

scholarly journals What functional genomics has taught us about transcriptional regulation in malaria parasites

2019 ◽  
Vol 18 (5) ◽  
pp. 290-301 ◽  
Author(s):  
Christa G Toenhake ◽  
Richárd Bártfai
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Life Cycle ◽  
Functional Genomics ◽  
Expression Patterns ◽  
Regulatory Elements ◽  
Complex Life Cycle ◽  
Malaria Parasites ◽  
Gene Regulatory

Abstract Malaria parasites are characterized by a complex life cycle that is accompanied by dynamic gene expression patterns. The factors and mechanisms that regulate gene expression in these parasites have been searched for even before the advent of next generation sequencing technologies. Functional genomics approaches have substantially boosted this area of research and have yielded significant insights into the interplay between epigenetic, transcriptional and post-transcriptional mechanisms. Recently, considerable progress has been made in identifying sequence-specific transcription factors and DNA-encoded regulatory elements. Here, we review the insights obtained from these efforts including the characterization of core promoters, the involvement of sequence-specific transcription factors in life cycle progression and the mapping of gene regulatory elements. Furthermore, we discuss recent developments in the field of functional genomics and how they might contribute to further characterization of this complex gene regulatory network.

scholarly journals Parasites are Particularly Problematic

2018 ◽  
Vol 2 ◽  
pp. e25604
Author(s):  
Susan Perkins
Keyword(s):  
Life Cycle ◽  
Intermediate Host ◽  
Information Content ◽  
Definitive Host ◽  
Complex Life Cycle ◽  
Phylogenetic Study ◽  
Biodiversity Informatics ◽  
Malaria Parasites ◽  
Parasitic Organism

Although they are hyperdiverse and intensively studied, parasites present major challenges when it comes to phylogenetics, taxonomy, and biodiversity informatics. The collection of any parasitic organism entails the linking of at least two specimens - the parasite and the host. If the parasite has a complex life cycle, then this becomes further complicated by requiring the linking of three or more hosts, such as the parasite, its intermediate host (vector) and its definitive host(s). Parasites are sometimes collected as byproduct of another collection event and are not studied immediately - which has the potential to disconnect them further in terms of information content and continuity- and the converse if also common - parasites can be collected by parasitologists, who do not necessarily take host vouchers or incorporate host taxonomy, let alone other metadata for these events. Using the specific example of the malaria parasites (Order Haemosporida) I will present examples of the specific challenges that have accompanied the study of these parasites including issues of delimiting species, phylogenetic study, including genetic oddities that are unique to these organisms, and taxonomic quandries that we now find ourselves in, along with other problems with maintaining continuity of information in a group that is both diverse biologically and important medically.

scholarly journals Characterization of Apicomplexan Amino Acid Transporters (ApiATs) in the Malaria Parasite Plasmodium falciparum

mSphere ◽  
2021 ◽  
Author(s):  
Jan Stephan Wichers ◽  
Carolina van Gelder ◽  
Gwendolin Fuchs ◽  
Julia Mareike Ruge ◽  
Emma Pietsch ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Amino Acid ◽  
Malaria Parasite ◽  
Host Cells ◽  
Amino Acid Transporters ◽  
Malaria Parasites ◽  
Parasite Plasmodium ◽  
Parasite Plasmodium Falciparum ◽  
Intracellular Proliferation

Malaria parasites live and multiply inside cells. To facilitate their extremely fast intracellular proliferation, they hijack and transform their host cells.

scholarly journals The ApiAP2 factor PfAP2-HC is an integral component of heterochromatin in the malaria parasite Plasmodium falciparum

2020 ◽  
Author(s):  
Eilidh Carrington ◽  
Roel H. M. Cooijmans ◽  
Dominique Keller ◽  
Christa G. Toenhake ◽  
Richárd Bártfai ◽  
...  
Keyword(s):  
Gene Expression ◽  
Plasmodium Falciparum ◽  
Life Cycle ◽  
Dna Binding ◽  
Regulation Of Gene Expression ◽  
Complex Life Cycle ◽  
Parasite Development ◽  
Specific Gene ◽  
Mosquito Vector ◽  
Malaria Parasites

AbstractMalaria parasites undergo a highly complex life cycle in the human host and the mosquito vector. The ApiAP2 family of sequence-specific DNA-binding proteins plays a dominant role in parasite development and life cycle progression. Of the ApiAP2 factors studied to date, most act as transcription factors regulating stage-specific gene expression. Here, we characterised a new ApiAP2 factor in Plasmodium falciparum (PF3D7_1456000) that we termed PfAP2-HC. Via detailed investigation of several single or double genetically engineered parasite lines, we demonstrate that PfAP2-HC specifically binds to heterochromatin throughout the genome. Intriguingly, PfAP2-HC does not bind DNA in vivo and recruitment of PfAP2-HC to heterochromatin is independent of its DNA-binding domain but strictly dependent on heterochromatin protein 1. Furthermore, our results suggest that PfAP2-HC functions neither in the regulation of gene expression nor in heterochromatin formation or maintenance. In summary, our findings reveal that PfAP2-HC constitutes a core component of heterochromatin in malaria parasites. They furthermore identify unexpected properties of ApiAP2 factors and suggest substantial functional divergence among the members of this important family of regulatory proteins.

scholarly journals Targeting SUMOylation in Plasmodium as a Potential Target for Malaria Therapy

2021 ◽  
Vol 11 ◽  
Author(s):  
Daffiny Sumam de Oliveira ◽  
Thales Kronenberger ◽  
Giuseppe Palmisano ◽  
Carsten Wrenger ◽  
Edmarcia Elisa de Souza
Keyword(s):  
Life Cycle ◽  
Molecular Mechanisms ◽  
Gene Expression Regulation ◽  
Public Health Problem ◽  
Complex Life Cycle ◽  
Cellular Functions ◽  
Cellular Mechanisms ◽  
Malaria Parasites ◽  
Malaria Therapy ◽  
Lysine Residues

Malaria is a parasitic disease that represents a public health problem worldwide. Protozoans of the Plasmodium genus are responsible for causing malaria in humans. Plasmodium species have a complex life cycle that requires post-translational modifications (PTMs) to control cellular activities temporally and spatially and regulate the levels of critical proteins and cellular mechanisms for maintaining an efficient infection and immune evasion. SUMOylation is a PTM formed by the covalent linkage of a small ubiquitin-like modifier protein to the lysine residues on the protein substrate. This PTM is reversible and is triggered by the sequential action of three enzymes: E1-activating, E2-conjugating, and E3 ligase. On the other end, ubiquitin-like-protein-specific proteases in yeast and sentrin-specific proteases in mammals are responsible for processing SUMO peptides and for deconjugating SUMOylated moieties. Further studies are necessary to comprehend the molecular mechanisms and cellular functions of SUMO in Plasmodium. The emergence of drug-resistant malaria parasites prompts the discovery of new targets and antimalarial drugs with novel mechanisms of action. In this scenario, the conserved biological processes regulated by SUMOylation in the malaria parasites such as gene expression regulation, oxidative stress response, ubiquitylation, and proteasome pathways, suggest PfSUMO as a new potential drug target. This mini-review focuses on the current understanding of the mechanism of action of the PfSUMO during the coordinated multi-step life cycle of Plasmodium and discusses them as attractive new target proteins for the development of parasite-specific inhibitors and therapeutic intervention toward malaria disease.

scholarly journals Exceptionally high sequence-level variation in the transcriptome of Plasmodium falciparum

2021 ◽  
Author(s):  
Bruhad Dave ◽  
Abhishek Kanyal ◽  
Mamatharani DV ◽  
Krishanpal Karmodiya
Keyword(s):  
Plasmodium Falciparum ◽  
Rna Editing ◽  
Complex Life Cycle ◽  
Specific Gene ◽  
Level Variation ◽  
Single Nucleotide ◽  
Parasite Plasmodium ◽  
Parasite Plasmodium Falciparum ◽  
Basic Biology ◽  
Parasite Biology

Single-nucleotide variations in RNA (hereafter referred to simply as SNVs), arising from co- and post-transcriptional phenomena including transcription errors and RNA editing, are well studied in organisms ranging from bacteria to humans. In the malaria parasite Plasmodium falciparum, stage-specific and non-specific gene-expression variations are known to accompany the parasite's array of developmental and morphological phenotypes over the course of its complex life cycle. However, the extent, rate and effect of sequence-level variation in the parasite's transcriptome are unknown. Here, we report the presence of pervasive, non-specific SNVs in the transcriptome of the P. falciparum. We show that these SNVs cover most of the parasite's transcriptome. SNV rates for the P. falciparum lines we assayed, as well as for publicly available P. vivax and P. falciparum clinical isolate datasets were of the order of 10-3 per base, about tenfold higher than rates we calculated for bacterial datasets. These SNVs may reflect an intrinsic transcriptional error rate in the parasite, and RNA editing may be responsible for a subset of them. This seemingly characteristic property of the parasite may have implications for clinical outcomes and the basic biology and evolution of P. falciparum and parasite biology more broadly, and we anticipate that our study will prompt further investigations into the exact sources, consequences and possible adaptive roles of these SNVs.

Sign in / Sign up

Export Citation Format

Share Document