Identification and Functional Analysis of the Primary Pantothenate Transporter, PfPAT, of the Human Malaria Parasite Plasmodium falciparum

Augagneur, Yoann; Jaubert, Lise; Schiavoni, Matthieu; Pachikara, Niseema; Garg, Aayushi; Usmani‐Brown, Sahar; Wesolowski, Donna; Zeller, Skye; Ghosal, Abhisek; Cornillot, Emmanuel; Said, Hamid M.; Kumar, Priti; Altman, Sidney; Mamoun, Choukri Ben

doi:10.1074/jbc.m113.482992

Cited by 41 publications

(39 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although a triose phosphate shuttle has been identified as a second source of reducing equivalents in the T. gondii apicoplast [117], there is no evidence for such a pathway in Plasmodium [21,26,112,185], leaving the balance of reducing power in the parasite organelle in apparent deficit. The source of the biotin, thiamine pyrophosphate and CoA required by ACC, PDH and ACPS are also somewhat unclear, with enzymes involved in the synthesis or scavenging of these cofactors identified in Plasmodium [26,187,188], but little research to date addressing their provision to the apicoplast [189][190][191][192][193]. To gain a more wholistic understanding of FASII, characterization of its remaining enzymes and elucidation of these underlying pathways is a necessity.…”

Section: Discussionmentioning

confidence: 99%

Fatty acid metabolism in the Plasmodium apicoplast: Drugs, doubts and knockouts

Shears

Botté

McFadden

2015

Molecular and Biochemical Parasitology

104

View full text Add to dashboard Cite

The malaria parasite Plasmodium possesses a relict, non-photosynthetic plastid known as the apicoplast. The apicoplast is essential for parasite survival, and harbors several plant-like metabolic pathways including a type II fatty acid synthesis (FASII) pathway. The FASII pathway was discovered in 1998, and much of the early research in the field pursued it as a therapeutic drug target. These studies identified a range of compounds with activity against bloodstage parasites and led to the localization and characterization of most enzymes in the pathway. However, when genetic studies revealed FASII was dispensable in bloodstage parasites, it effectively discounted the pathway as a therapeutic drug target, and suggested these compounds instead interfered with other processes. Interest in FASII then shifted toward its disruption for malaria prophylaxis and vaccine development, with experiments in rodent malaria models identifying a crucial role for the pathway in the parasite's transition from the liver to the blood. Unexpectedly however, the human malaria parasite P. falciparum was recently found to differ from rodent models and require FASII for mosquito stage development. This requirement blocked the production of the FASII-deficient forms that might be used as a genetically attenuated parasite vaccine, suggesting the pathway was also unsuitable as a vaccine target. This review discusses how perception of FASII has changed over time, and presents key findings about each enzyme in the pathway to identify remaining questions and opportunities for malaria control.

show abstract

Section: Discussionmentioning

confidence: 99%

Fatty acid metabolism in the Plasmodium apicoplast: Drugs, doubts and knockouts

Shears

Botté

McFadden

2015

Molecular and Biochemical Parasitology

104

View full text Add to dashboard Cite

show abstract

“…For example, MOs with External Guide Sequence (EGS) conjugated to peptides (PPMOs) have been designed to target essential genes of several pathogenic bacteria and have displayed strong antibacterial activity (10)(11)(12)(13). Similarly, PPMOs targeting the P. falciparum PfGyrA and PfPAT RNAs for RNase P-mediated cleavage inhibit parasite growth in the low micromolar range (4,(14)(15)(16). Because binding of MOs to their target RNAs can prevent binding of other molecules to the same targets, MO conjugates have also been used to inhibit RNA splicing and initiation of protein translation (9,17,18).…”

mentioning

confidence: 99%

Targeting protein translation, RNA splicing, and degradation by morpholino-based conjugates in Plasmodium falciparum

Garg

Wesolowski

Alonso

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

Identification and genetic validation of new targets from available genome sequences are critical steps toward the development of new potent and selective antimalarials. However, no methods are currently available for large-scale functional analysis of the Plasmodium falciparum genome. Here we present evidence for successful use of morpholino oligomers (MO) to mediate degradation of target mRNAs or to inhibit RNA splicing or translation of several genes of P. falciparum involved in chloroquine transport, apicoplast biogenesis, and phospholipid biosynthesis. Consistent with their role in the parasite life cycle, down-regulation of these essential genes resulted in inhibition of parasite development. We show that a MO conjugate that targets the chloroquine-resistant transporter PfCRT is effective against chloroquine-sensitive and -resistant parasites, causes enlarged digestive vacuoles, and renders chloroquine-resistant strains more sensitive to chloroquine. Similarly, we show that a MO conjugate that targets the PfDXR involved in apicoplast biogenesis inhibits parasite growth and that this defect can be rescued by addition of isopentenyl pyrophosphate. MO-based gene regulation is a viable alternative approach to functional analysis of the P. falciparum genome. malaria | intraerythrocytic development | peptide conjugated morpholino oligomer | vivo morpholino oligomer | gene expression

show abstract

“…(a) Discrepancies in localisation data obtained for Plasmodium transporters Two very different patterns of localisation have been reported for TFP1. A GFP-tagged version of TFP1 localised to the surface of the asexual intraerythrocytic parasite when expressed from an episomal plasmid and under the control of a non-endogenous promoter (Augagneur et al, 2013). However, when expressed from its native locus and promoter, GFP-tagged TFP1 was not evident in asexual blood-stage parasites and the recombinant transporter was instead localised to the osmiophilic body of gametocytes and the micronemes and surface of sporozoites (Kehrer et al, 2016).…”

Section: Figmentioning

confidence: 99%

“…That said, a number of attempts to express Plasmodium transporters in yeast have been unsuccessful (Henry et al, 2007;Lim et al, 2010), and others have either been queried (e.g. the putative pantothenate transporter PfPAT (Augagneur et al, 2013) also known as PfTFP1 (Kehrer et al, 2016); see Section V.4b and Table S2) or retracted altogether (e.g. PfMDR1; Ruetz et al, 1999).…”

Section: (4) Known or Predicted Transport Functionsmentioning

confidence: 99%

The transportome of the malaria parasite

Martin

2019

Biological Reviews

View full text Add to dashboard Cite

Membrane transport proteins, also known as transporters, control the movement of ions, nutrients, metabolites, and waste products across the membranes of a cell and are central to its biology. Proteins of this type also serve as drug targets and are key players in the phenomenon of drug resistance. The malaria parasite has a relatively reduced transportome, with only approximately 2.5% of its genes encoding transporters. Even so, assigning functions and physiological roles to these proteins, and ascertaining their contributions to drug action and drug resistance, has been very challenging. This review presents a detailed critique and synthesis of the disruption phenotypes, protein subcellular localisations, protein functions (observed or predicted), and links to antimalarial drug resistance for each of the parasite's transporter genes. The breadth and depth of the gene disruption data are particularly impressive, with at least one phenotype determined in the parasite's asexual blood stage for each transporter gene, and multiple phenotypes available for 76% of the genes. Analysis of the curated data set revealed there to be relatively little redundancy in the Plasmodium transportome; almost two‐thirds of the parasite's transporter genes are essential or required for normal growth in the asexual blood stage of the parasite, and this proportion increased to 78% when the disruption phenotypes available for the other parasite life stages were included in the analysis. These observations, together with the finding that 22% of the transportome is implicated in the parasite's resistance to existing antimalarials and/or drugs within the development pipeline, indicate that transporters are likely to serve, or are already serving, as drug targets. Integration of the different biological and bioinformatic data sets also enabled the selection of candidates for transport processes known to be essential for parasite survival, but for which the underlying proteins have thus far remained undiscovered. These include potential transporters of pantothenate, isoleucine, or isopentenyl diphosphate, as well as putative anion‐selective channels that may serve as the pore component of the parasite's ‘new permeation pathways’. Other novel insights into the parasite's biology included the identification of transporters for the potential development of antimalarial treatments, transmission‐blocking drugs, prophylactics, and genetically attenuated vaccines. The syntheses presented herein set a foundation for elucidating the functions and physiological roles of key members of the Plasmodium transportome and, ultimately, to explore and realise their potential as therapeutic targets.

show abstract

Identification and Functional Analysis of the Primary Pantothenate Transporter, PfPAT, of the Human Malaria Parasite Plasmodium falciparum

Cited by 41 publications

References 42 publications

Fatty acid metabolism in the Plasmodium apicoplast: Drugs, doubts and knockouts

Fatty acid metabolism in the Plasmodium apicoplast: Drugs, doubts and knockouts

Targeting protein translation, RNA splicing, and degradation by morpholino-based conjugates in Plasmodium falciparum

The transportome of the malaria parasite

Contact Info

Product

Resources

About