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Lu J, Tong Y, Dong R, Yang Y, Hu W, Zhang M, Liu Q, Zhao S, Adams JH, Qin L, Chen X. Large DNA fragment knock-in and sequential gene editing in Plasmodium falciparum: a preliminary study using suicide-rescue-based CRISPR/Cas9 system. Mol Cell Biochem 2024; 479:99-107. [PMID: 37004637 PMCID: PMC10066980 DOI: 10.1007/s11010-023-04711-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/15/2023] [Indexed: 04/04/2023]
Abstract
CRISPR/Cas9 technology applied to Plasmodium falciparum offers the potential to greatly improve gene editing, but such expectations including large DNA fragment knock-ins and sequential gene editing have remained unfulfilled. Here, we achieved a major advance in addressing this challenge, especially for creating large DNA fragment knock-ins and sequential editing, by modifying our suicide-rescue-based system that has already been demonstrated to be highly efficient for conventional gene editing. This improved approach was confirmed to mediate efficient knock-ins of DNA fragments up to 6.3 kb, to produce "marker-free" genetically engineered parasites and to show potential for sequential gene editing. This represents an important advancement in establishing platforms for large-scale genome editing, which might gain a better understanding of gene function for the most lethal cause of malaria and contribute to adjusting synthetic biology strategies to live parasite malaria vaccine development. Site-directed knock-in of large DNA fragments is highly efficient using suicide-rescue-based CRISPR/Cas9 system, and sequential gene insertion is feasible but further confirmation is still needed.
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Affiliation(s)
- Junnan Lu
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, People's Republic of China
| | - Ying Tong
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
| | - Rui Dong
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
| | - Yijun Yang
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, People's Republic of China
| | - Wen Hu
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
| | - Minghong Zhang
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
| | - Quan Liu
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
- University of Chinese Academy of Sciences, No.19 (A) Yuquan Road, Shijingshan District, Beijing, 100049, People's Republic of China
| | - Siting Zhao
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
| | - John H Adams
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, 3720 Spectrum Blvf Suite 404, Tampa, FL, 33612, USA
| | - Li Qin
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China.
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China.
| | - Xiaoping Chen
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China.
- CAS Lamvac Biotech Co., Ltd., No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, People's Republic of China.
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2
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Chahine Z, Abel S, Hollin T, Chung JH, Barnes GL, Daub ME, Renard I, Choi JY, Pratap V, Pal A, Alba-Argomaniz M, Banks CAS, Kirkwood J, Saraf A, Camino I, Castaneda P, Cuevas MC, De Mercado-Arnanz J, Fernandez-Alvaro E, Garcia-Perez A, Ibarz N, Viera-Morilla S, Prudhomme J, Joyner CJ, Bei AK, Florens L, Ben Mamoun C, Vanderwal CD, Le Roch KG. A Potent Kalihinol Analogue Disrupts Apicoplast Function and Vesicular Trafficking in P. falciparum Malaria. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.21.568162. [PMID: 38045341 PMCID: PMC10690269 DOI: 10.1101/2023.11.21.568162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Here we report the discovery of MED6-189, a new analogue of the kalihinol family of isocyanoterpene (ICT) natural products. MED6-189 is effective against drug-sensitive and -resistant P. falciparum strains blocking both intraerythrocytic asexual replication and sexual differentiation. This compound was also effective against P. knowlesi and P. cynomolgi. In vivo efficacy studies using a humanized mouse model of malaria confirms strong efficacy of the compound in animals with no apparent hemolytic activity or apparent toxicity. Complementary chemical biology, molecular biology, genomics and cell biological analyses revealed that MED6-189 primarily targets the parasite apicoplast and acts by inhibiting lipid biogenesis and cellular trafficking. Genetic analyses in P. falciparum revealed that a mutation in PfSec13, which encodes a component of the parasite secretory machinery, reduced susceptibility to the drug. The high potency of MED6-189 in vitro and in vivo, its broad range of efficacy, excellent therapeutic profile, and unique mode of action make it an excellent addition to the antimalarial drug pipeline.
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Affiliation(s)
- Z Chahine
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - S Abel
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - T Hollin
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - JH Chung
- Department of Chemistry, University of California, Irvine, California, 92617, USA
| | - GL Barnes
- Department of Chemistry, University of California, Irvine, California, 92617, USA
| | - ME Daub
- Department of Chemistry, University of California, Irvine, California, 92617, USA
| | - I Renard
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - JY Choi
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - V Pratap
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - A Pal
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - M Alba-Argomaniz
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
| | - CAS Banks
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO 64110, USA
| | - J Kirkwood
- Metabolomics Core Facility, University of California, Riverside, CA 92521, USA
| | - A Saraf
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO 64110, USA
| | - I Camino
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | - P Castaneda
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | - MC Cuevas
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | | | | | - A Garcia-Perez
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | - N Ibarz
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | - S Viera-Morilla
- GSK, C/ Severo Ochoa, 2 PTM, 28760 Tres Cantos (Madrid), Spain
| | - J Prudhomme
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
| | - CJ Joyner
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
| | - AK Bei
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - L Florens
- Stowers Institute for Medical Research, 1000 E. 50th Street, Kansas City, MO 64110, USA
| | - C Ben Mamoun
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - CD Vanderwal
- Department of Chemistry, University of California, Irvine, California, 92617, USA
| | - KG Le Roch
- Department of Molecular, Cell and Systems Biology, University of California Riverside, CA, USA
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3
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Viegas J. Profile of Daniel E. Goldberg. Proc Natl Acad Sci U S A 2023; 120:e2314435120. [PMID: 37722042 PMCID: PMC10523458 DOI: 10.1073/pnas.2314435120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023] Open
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4
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Schneider V, Visone J, Harris C, Florini F, Hadjimichael E, Zhang X, Gross M, Rhee K, Ben Mamoun C, Kafsack B, Deitsch K. The human malaria parasite Plasmodium falciparum can sense environmental changes and respond by antigenic switching. Proc Natl Acad Sci U S A 2023; 120:e2302152120. [PMID: 37068249 PMCID: PMC10151525 DOI: 10.1073/pnas.2302152120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/20/2023] [Indexed: 04/19/2023] Open
Abstract
The primary antigenic and virulence determinant of the human malaria parasite Plasmodium falciparum is a variant surface protein called PfEMP1. Different forms of PfEMP1 are encoded by a multicopy gene family called var, and switching between active genes enables the parasites to evade the antibody response of their human hosts. var gene switching is key for the maintenance of chronic infections; however, what controls switching is unknown, although it has been suggested to occur at a constant frequency with little or no environmental influence. var gene transcription is controlled epigenetically through the activity of histone methyltransferases (HMTs). Studies in model systems have shown that metabolism and epigenetic control of gene expression are linked through the availability of intracellular S-adenosylmethionine (SAM), the principal methyl donor in biological methylation modifications, which can fluctuate based on nutrient availability. To determine whether environmental conditions and changes in metabolism can influence var gene expression, P. falciparum was cultured in media with altered concentrations of nutrients involved in SAM metabolism. We found that conditions that influence lipid metabolism induce var gene switching, indicating that parasites can respond to changes in their environment by altering var gene expression patterns. Genetic modifications that directly modified expression of the enzymes that control SAM levels similarly led to profound changes in var gene expression, confirming that changes in SAM availability modulate var gene switching. These observations directly challenge the paradigm that antigenic variation in P. falciparum follows an intrinsic, programed switching rate, which operates independently of any external stimuli.
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Affiliation(s)
- Victoria M. Schneider
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
- Laboratory of Chemical Biology and Microbial Pathogenesis, Rockefeller University, New York, NY 10065
| | - Joseph E. Visone
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Chantal T. Harris
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Francesca Florini
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Evi Hadjimichael
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Xu Zhang
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Mackensie R. Gross
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Kyu Y. Rhee
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Choukri Ben Mamoun
- Section of Infectious Disease, Department of Microbial Pathogenesis, Yale School of Medicine, Yale University New Haven, CT 06510
| | - Björn F. C. Kafsack
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
| | - Kirk W. Deitsch
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, Ithaca, NY14853
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5
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Li H, Zhao J, Ding W, Zhang Q. Glucuronyl C4 dehydrogenation by the radical SAM enzyme BlsE involved in blasticidin S biosynthesis. Chem Commun (Camb) 2022; 58:3561-3564. [PMID: 35199117 DOI: 10.1039/d1cc07132g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Here we report functional investigation of the radical S-adenosylmethionine enzyme BlsE by using cytosylglucuronamide (CGM), which is the amide analog of cytosylglucuronic acid (CGA), an intermediate involved in blasticidin S biosynthesis. We showed that, instead of decarboxylation of CGA reported previously, BlsE catalyzes C4'-dehydrogenation of CGM, and the resulting ketone is acted on by an aminotransferase BlsH to install the C4'-amino group, which uses L-Asp as the amino donor.
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Affiliation(s)
- He Li
- Department of Chemistry, Fudan University, Shanghai, 200433, China.
| | - Junfeng Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wei Ding
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qi Zhang
- Department of Chemistry, Fudan University, Shanghai, 200433, China.
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6
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Okada M, Rajaram K, Swift RP, Mixon A, Maschek JA, Prigge ST, Sigala PA. Critical role for isoprenoids in apicoplast biogenesis by malaria parasites. eLife 2022; 11:73208. [PMID: 35257658 PMCID: PMC8959605 DOI: 10.7554/elife.73208] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 03/04/2022] [Indexed: 11/13/2022] Open
Abstract
Isopentenyl pyrophosphate (IPP) is an essential metabolic output of the apicoplast organelle in Plasmodium falciparum malaria parasites and is required for prenylation-dependent vesicular trafficking and other cellular processes. We have elucidated a critical and previously uncharacterized role for IPP in apicoplast biogenesis. Inhibiting IPP synthesis blocks apicoplast elongation and inheritance by daughter merozoites, and apicoplast biogenesis is rescued by exogenous IPP and polyprenols. Knockout of the only known isoprenoid-dependent apicoplast pathway, tRNA prenylation by MiaA, has no effect on blood-stage parasites and thus cannot explain apicoplast reliance on IPP. However, we have localized an annotated polyprenyl synthase (PPS) to the apicoplast. PPS knockdown is lethal to parasites, rescued by IPP and long- (C50) but not short-chain (≤C20) prenyl alcohols, and blocks apicoplast biogenesis, thus explaining apicoplast dependence on isoprenoid synthesis. We hypothesize that PPS synthesizes long-chain polyprenols critical for apicoplast membrane fluidity and biogenesis. This work critically expands the paradigm for isoprenoid utilization in malaria parasites and identifies a novel essential branch of apicoplast metabolism suitable for therapeutic targeting.
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Affiliation(s)
- Megan Okada
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - Krithika Rajaram
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
| | - Russell P Swift
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
| | - Amanda Mixon
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - John Alan Maschek
- Metabolomics Core, University of Utah, Salt Lake City, United States
| | - Sean T Prigge
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
| | - Paul A Sigala
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
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7
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Wang S, Zeng W, Zhao W, Xiang Z, Zhao H, Yang Q, Li X, Duan M, Li X, Wang X, Si Y, Rosenthal BM, Yang Z. Comparison of in vitro transformation efficiency methods for Plasmodium falciparum. Mol Biochem Parasitol 2021; 247:111432. [PMID: 34826523 DOI: 10.1016/j.molbiopara.2021.111432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/03/2021] [Accepted: 11/19/2021] [Indexed: 11/30/2022]
Abstract
Poor efficiency plagues conventional methods to transfect Plasmodium falciparum with genetic modifications, impeding research aimed at limiting the damage wrought by this agent of severe malaria. Here, we sought and documented improvements, using fluoresce imaging, cell sorting, and drug selection as means to measure efficiency. Through the transfection of EGFP plasmid, the transfection efficiency of the three methods used in this study was as high as 10-3. A method that pre-loaded uninfected erythrocytes with plasmids using the Bio-Rad Gene Pulser Xcell achieved the highest efficiency (0.48%±0.06%), twice the efficiency of a method using nuclear transfection of ring stages employing the 4D-NucleofectorTM X Kit L. We also evaluated an approach using the Nucleofactor system to transform schizont stages. We considered efficiency and the time required to complete drug screening experiments when evaluating transfection methods. Fluorescence measurements confirmed greater efficiencies for the Pre-load method (52.4% vs. 25%; P < 0.0001), but the Nuc-Ring method required less time to complete drug selection experiments following CRISPR/Cas9 editing. These data should benefit future studies seeking to remove or modify genes of P. falciparum.
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Affiliation(s)
- Siqi Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China; National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology (National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention), Shanghai, 200025, China
| | - Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Wei Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Zheng Xiang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Hui Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Qi Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Xinxin Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Mengxi Duan
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Xiaosong Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Xun Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Yu Si
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Benjamin M Rosenthal
- Animal Parasitic Disease Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, United States Department of Agriculture, Beltsville, MD 20705, USA
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, Yunnan Province 650500, China.
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8
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Murithi JM, Pascal C, Bath J, Boulenc X, Gnädig NF, Pasaje CFA, Rubiano K, Yeo T, Mok S, Klieber S, Desert P, Jiménez-Díaz MB, Marfurt J, Rouillier M, Cherkaoui-Rbati MH, Gobeau N, Wittlin S, Uhlemann AC, Price RN, Wirjanata G, Noviyanti R, Tumwebaze P, Cooper RA, Rosenthal PJ, Sanz LM, Gamo FJ, Joseph J, Singh S, Bashyam S, Augereau JM, Giraud E, Bozec T, Vermat T, Tuffal G, Guillon JM, Menegotto J, Sallé L, Louit G, Cabanis MJ, Nicolas MF, Doubovetzky M, Merino R, Bessila N, Angulo-Barturen I, Baud D, Bebrevska L, Escudié F, Niles JC, Blasco B, Campbell S, Courtemanche G, Fraisse L, Pellet A, Fidock DA, Leroy D. The antimalarial MMV688533 provides potential for single-dose cures with a high barrier to Plasmodium falciparum parasite resistance. Sci Transl Med 2021; 13:13/603/eabg6013. [PMID: 34290058 PMCID: PMC8530196 DOI: 10.1126/scitranslmed.abg6013] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 07/02/2021] [Indexed: 01/13/2023]
Abstract
The emergence and spread of Plasmodium falciparum resistance to first-line antimalarials creates an imperative to identify and develop potent preclinical candidates with distinct modes of action. Here, we report the identification of MMV688533, an acylguanidine that was developed following a whole-cell screen with compounds known to hit high-value targets in human cells. MMV688533 displays fast parasite clearance in vitro and is not cross-resistant with known antimalarials. In a P. falciparum NSG mouse model, MMV688533 displays a long-lasting pharmacokinetic profile and excellent safety. Selection studies reveal a low propensity for resistance, with modest loss of potency mediated by point mutations in PfACG1 and PfEHD. These proteins are implicated in intracellular trafficking, lipid utilization, and endocytosis, suggesting interference with these pathways as a potential mode of action. This preclinical candidate may offer the potential for a single low-dose cure for malaria.
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Affiliation(s)
- James M. Murithi
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Cécile Pascal
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Jade Bath
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | | | - Nina F. Gnädig
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | | | - Kelly Rubiano
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Tomas Yeo
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Sachel Mok
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Sylvie Klieber
- Sanofi R&D, Translational Medicine & Early Development, Montpellier, France
| | | | | | - Jutta Marfurt
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | | | | | | | - Sergio Wittlin
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,Universität Basel, Basel, Switzerland
| | - Anne-Catrin Uhlemann
- Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Ric N. Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.,Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Grennady Wirjanata
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Australia
| | | | | | - Roland A. Cooper
- Department of Natural Sciences and Mathematics, Dominican University of California, San Rafael, CA, USA
| | | | - Laura M. Sanz
- Global Health Pharma Research Unit, GSK, Tres Cantos, Madrid, Spain
| | | | | | | | | | | | - Elie Giraud
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Tanguy Bozec
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Thierry Vermat
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Gilles Tuffal
- Sanofi R&D, Translational Medicine & Early Development, Montpellier, France
| | | | - Jérôme Menegotto
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Laurent Sallé
- Sanofi R&D, Translational Medicine & Early Development, Montpellier, France
| | | | - Marie-José Cabanis
- Sanofi R&D, Translational Medicine & Early Development, Montpellier, France
| | | | | | - Rita Merino
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Nadir Bessila
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | | | | | | | | | - Jacquin C. Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | | | | | - Laurent Fraisse
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - Alain Pellet
- Sanofi, Infectious Diseases Therapeutic Area, Marcy l'Etoile, France
| | - David A. Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA.,Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA.,Corresponding author. (D.A.F.); (D.L.)
| | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland.,Corresponding author. (D.A.F.); (D.L.)
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9
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Polino AJ, Nasamu AS, Niles JC, Goldberg DE. Assessment of Biological Role and Insight into Druggability of the Plasmodium falciparum Protease Plasmepsin V. ACS Infect Dis 2020; 6:738-746. [PMID: 32069391 PMCID: PMC7155168 DOI: 10.1021/acsinfecdis.9b00460] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Indexed: 01/05/2023]
Abstract
Upon infecting a red blood cell (RBC), the malaria parasite Plasmodium falciparum drastically remodels its host by exporting hundreds of proteins into the RBC cytosol. This protein export program is essential for parasite survival. Hence export-related proteins could be potential drug targets. One essential enzyme in this pathway is plasmepsin V (PMV), an aspartic protease that processes export-destined proteins in the parasite endoplasmic reticulum (ER) at the Plasmodium export element (PEXEL) motif. Despite long-standing interest in this enzyme, functional studies have been hindered by the inability of previous technologies to produce a regulatable lethal depletion of PMV. To overcome this technical barrier, we designed a system for stringent post-transcriptional regulation allowing a tightly controlled, tunable knockdown of PMV. Using this system, we found that PMV must be dramatically depleted to affect parasite growth, suggesting the parasite maintains this enzyme in substantial excess. Surprisingly, depletion of PMV arrested parasite growth immediately after RBC invasion, significantly before the death from exported protein deficit that has previously been described. The data suggest that PMV inhibitors can halt parasite growth at two distinct points in the parasite life cycle. However, overcoming the functional excess of PMV in the parasite may require inhibitor concentrations far beyond the enzyme's IC50.
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Affiliation(s)
- Alexander J Polino
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Armiyaw S Nasamu
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Daniel E Goldberg
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
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10
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Gnädig NF, Stokes BH, Edwards RL, Kalantarov GF, Heimsch KC, Kuderjavy M, Crane A, Lee MCS, Straimer J, Becker K, Trakht IN, Odom John AR, Mok S, Fidock DA. Insights into the intracellular localization, protein associations and artemisinin resistance properties of Plasmodium falciparum K13. PLoS Pathog 2020; 16:e1008482. [PMID: 32310999 PMCID: PMC7192513 DOI: 10.1371/journal.ppat.1008482] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 04/30/2020] [Accepted: 03/17/2020] [Indexed: 12/23/2022] Open
Abstract
The emergence of artemisinin (ART) resistance in Plasmodium falciparum intra-erythrocytic parasites has led to increasing treatment failure rates with first-line ART-based combination therapies in Southeast Asia. Decreased parasite susceptibility is caused by K13 mutations, which are associated clinically with delayed parasite clearance in patients and in vitro with an enhanced ability of ring-stage parasites to survive brief exposure to the active ART metabolite dihydroartemisinin. Herein, we describe a panel of K13-specific monoclonal antibodies and gene-edited parasite lines co-expressing epitope-tagged versions of K13 in trans. By applying an analytical quantitative imaging pipeline, we localize K13 to the parasite endoplasmic reticulum, Rab-positive vesicles, and sites adjacent to cytostomes. These latter structures form at the parasite plasma membrane and traffic hemoglobin to the digestive vacuole wherein artemisinin-activating heme moieties are released. We also provide evidence of K13 partially localizing near the parasite mitochondria upon treatment with dihydroartemisinin. Immunoprecipitation data generated with K13-specific monoclonal antibodies identify multiple putative K13-associated proteins, including endoplasmic reticulum-resident molecules, mitochondrial proteins, and Rab GTPases, in both K13 mutant and wild-type isogenic lines. We also find that mutant K13-mediated resistance is reversed upon co-expression of wild-type or mutant K13. These data help define the biological properties of K13 and its role in mediating P. falciparum resistance to ART treatment.
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Affiliation(s)
- Nina F. Gnädig
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Barbara H. Stokes
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Rachel L. Edwards
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Gavreel F. Kalantarov
- Department of Medicine, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Kim C. Heimsch
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | | | - Audrey Crane
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Marcus C. S. Lee
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Judith Straimer
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | - Ilya N. Trakht
- Department of Medicine, Columbia University Irving Medical Center, New York, NY, United States of America
| | - Audrey R. Odom John
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, United States of America
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, United States of America
- Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Sachel Mok
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
| | - David A. Fidock
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, United States of America
- Department of Medicine, Columbia University Irving Medical Center, New York, NY, United States of America
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11
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Loesbanluechai D, Kotanan N, de Cozar C, Kochakarn T, Ansbro MR, Chotivanich K, White NJ, Wilairat P, Lee MCS, Gamo FJ, Sanz LM, Chookajorn T, Kümpornsin K. Overexpression of plasmepsin II and plasmepsin III does not directly cause reduction in Plasmodium falciparum sensitivity to artesunate, chloroquine and piperaquine. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2018; 9:16-22. [PMID: 30580023 PMCID: PMC6304341 DOI: 10.1016/j.ijpddr.2018.11.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 11/22/2018] [Accepted: 11/24/2018] [Indexed: 01/31/2023]
Abstract
Artemisinin derivatives and their partner drugs in artemisinin combination therapies (ACTs) have played a pivotal role in global malaria mortality reduction during the last two decades. The loss of artemisinin efficacy due to evolving drug-resistant parasites could become a serious global health threat. Dihydroartemisinin-piperaquine is a well tolerated and generally highly effective ACT. The implementation of a partner drug in ACTs is critical in the control of emerging artemisinin resistance. Even though artemisinin is highly effective in parasite clearance, it is labile in the human body. A partner drug is necessary for killing the remaining parasites when the pulses of artemisinin have ceased. A population of Plasmodium falciparum parasites in Cambodia and adjacent countries has become resistant to piperaquine. Increased copy number of the genes encoding the haemoglobinases Plasmepsin II and Plasmepsin III has been linked with piperaquine resistance by genome-wide association studies and in clinical trials, leading to the use of increased plasmepsin II/plasmepsin III copy number as a molecular marker for piperaquine resistance. Here we demonstrate that overexpression of plasmepsin II and plasmepsin III in the 3D7 genetic background failed to change the susceptibility of P. falciparum to artemisinin, chloroquine and piperaquine by both a standard dose-response analysis and a piperaquine survival assay. Whilst plasmepsin copy number polymorphism is currently implemented as a molecular surveillance resistance marker, further studies to discover the molecular basis of piperaquine resistance and potential epistatic interactions are needed.
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Affiliation(s)
- Duangkamon Loesbanluechai
- Genomics and Evolutionary Medicine Unit (GEM), Centre of Excellence in Malaria Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand; Molecular Medicine Program, Multidisciplinary Unit, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Namfon Kotanan
- Genomics and Evolutionary Medicine Unit (GEM), Centre of Excellence in Malaria Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Cristina de Cozar
- Tres Cantos Medicine Development Campus, GlaxoSmithKline, Parque Tecnológico de Madrid, Tres Cantos, 28760, Spain
| | - Theerarat Kochakarn
- Genomics and Evolutionary Medicine Unit (GEM), Centre of Excellence in Malaria Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Megan R Ansbro
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA; Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, United Kingdom
| | - Kesinee Chotivanich
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Churchill Hospital, Oxford, OX3 7LJ, United Kingdom
| | - Prapon Wilairat
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Marcus C S Lee
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, United Kingdom
| | - Francisco Javier Gamo
- Tres Cantos Medicine Development Campus, GlaxoSmithKline, Parque Tecnológico de Madrid, Tres Cantos, 28760, Spain
| | - Laura Maria Sanz
- Tres Cantos Medicine Development Campus, GlaxoSmithKline, Parque Tecnológico de Madrid, Tres Cantos, 28760, Spain
| | - Thanat Chookajorn
- Genomics and Evolutionary Medicine Unit (GEM), Centre of Excellence in Malaria Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
| | - Krittikorn Kümpornsin
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, United Kingdom.
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12
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Sakamoto H, Hirakawa Y, Ishida KI, Keeling PJ, Kita K, Matsuzaki M. Puromycin selection for stable transfectants of the oyster-infecting parasite Perkinsus marinus. Parasitol Int 2018; 69:13-16. [PMID: 30389616 DOI: 10.1016/j.parint.2018.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 10/25/2018] [Accepted: 10/29/2018] [Indexed: 01/28/2023]
Abstract
Perkinsus marinus is a marine protozoan parasite that infects natural and farmed oysters, attracting attention from researchers in both fisheries and evolutionary biology. The functions of almost all cellular components and organelles are, however, poorly understood even though a draft genome sequence of P. marinus is publicly available. One of the major obstacles for a functional study of the parasite is limited experimental means for genetic manipulation: a transfection method was established in 2008, and the first drug selection system with bleomycin was reported in 2016. We here introduce the second drug-selectable marker for selection of P. marinus transfectants. The parasite growth is efficiently inhibited by puromycin (IC50 = 4.96 μg/mL), and transfection of its resistance gene, puromycin-N-acetyl-transferase (pac), confers resistance to the drug on the parasite. Stable transfectants can be obtained within 2 months by treating with puromycin at 100 μg/mL. Furthermore, combining puromycin and bleomycin treatment can select transfectants co-expressing two marker genes. This dual-transfection method raises the possibility of using co-localization to identify the cellular localization of novel proteins in P. marinus, thereby contributing to the understanding of cellular functions and pathogenesis.
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Affiliation(s)
- Hirokazu Sakamoto
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yoshihisa Hirakawa
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Ken-Ichiro Ishida
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Motomichi Matsuzaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
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13
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Balabaskaran-Nina P, Desai SA. Diverse target gene modifications in Plasmodium falciparum using Bxb1 integrase and an intronic attB. Parasit Vectors 2018; 11:548. [PMID: 30333047 PMCID: PMC6192176 DOI: 10.1186/s13071-018-3129-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 10/01/2018] [Indexed: 12/26/2022] Open
Abstract
Genetic manipulation of the human malaria parasite Plasmodium falciparum is needed to explore pathogen biology and evaluate antimalarial targets. It is, however, aggravated by a low transfection efficiency, a paucity of selectable markers and a biased A/T-rich genome. While various enabling technologies have been introduced over the past two decades, facile and broad-range modification of essential genes remains challenging. We recently devised a new application of the Bxb1 integrase strategy to meet this need through an intronic attB sequence within the gene of interest. Although this attB is silent and without effect on intron splicing or protein translation and function, it allows efficient gene modification with minimal risk of unwanted changes at other genomic sites. We describe the range of applications for this new method as well as specific cases where it is preferred over CRISPR-Cas9 and other technologies. The advantages and limitations of various strategies for endogenous gene editing are also discussed.
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Affiliation(s)
- Praveen Balabaskaran-Nina
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA.,Present Address: Department of Epidemiology and Public Health, Central University of Tamil Nadu, Thiruvarur, India
| | - Sanjay A Desai
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA.
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14
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Ribeiro JM, Garriga M, Potchen N, Crater AK, Gupta A, Ito D, Desai SA. Guide RNA selection for CRISPR-Cas9 transfections in Plasmodium falciparum. Int J Parasitol 2018; 48:825-832. [PMID: 29906414 PMCID: PMC9093057 DOI: 10.1016/j.ijpara.2018.03.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 03/11/2018] [Accepted: 03/13/2018] [Indexed: 12/26/2022]
Abstract
CRISPR-Cas9 mediated genome editing is addressing key limitations in the transfection of malaria parasites. While this method has already simplified the needed molecular cloning and reduced the time required to generate mutants in the human pathogen Plasmodium falciparum, optimal selection of required guide RNAs and guidelines for successful transfections have not been well characterised, leading workers to use time-consuming trial and error approaches. We used a genome-wide computational approach to create a comprehensive and publicly accessible database of possible guide RNA sequences in the P. falciparum genome. For each guide, we report on-target efficiency and specificity scores as well as information about the genomic site relevant to optimal design of CRISPR-Cas9 transfections to modify, disrupt, or conditionally knockdown any gene. As many antimalarial drug and vaccine targets are encoded by multigene families, we also developed a new paralog specificity score that should facilitate modification of either a single family member of interest or multiple paralogs that serve overlapping roles. Finally, we tabulated features of successful transfections in our laboratory, providing broadly useful guidelines for parasite transfections. Molecular studies aimed at understanding parasite biology or characterising drug and vaccine targets in P. falciparum should be facilitated by this comprehensive database.
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Affiliation(s)
- Jose M Ribeiro
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Meera Garriga
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Nicole Potchen
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Anna K Crater
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Ankit Gupta
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Daisuke Ito
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Sanjay A Desai
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA.
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15
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Soga A, Ko‐ketsu M, Fukumoto S. Development of a
bsd
‐blasticidin selection system in
Plasmodium berghei. FEBS Lett 2018; 592:1847-1855. [DOI: 10.1002/1873-3468.13100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Akira Soga
- National Research Center for Protozoan Diseases Obihiro University of Agriculture and Veterinary Medicine Japan
| | - Mami Ko‐ketsu
- National Research Center for Protozoan Diseases Obihiro University of Agriculture and Veterinary Medicine Japan
| | - Shinya Fukumoto
- National Research Center for Protozoan Diseases Obihiro University of Agriculture and Veterinary Medicine Japan
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16
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Soga A, Bando H, Ko-Ketsu M, Masuda-Suganuma H, Kawazu SI, Fukumoto S. High efficacy in vitro selection procedure for generating transgenic parasites of Plasmodium berghei using an antibiotic toxic to rodent hosts. Sci Rep 2017. [PMID: 28638105 PMCID: PMC5479828 DOI: 10.1038/s41598-017-04244-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The malaria parasite Plasmodium berghei is one of the main rodent malaria models. A shortcoming of this model parasite is its low flexibility in genetic manipulation. As this parasite cannot be continuously propagated in cell cultures, in vivo drug selection procedures are necessary to isolate genetic mutants. Drugs harmful to rodents therefore cannot be used for drug selection, which restricts the range of genetic manipulation. In this study, we addressed this problem by establishing a novel in vitro culture drug selection method, which we used in combination with other established methods to successfully isolate genetically manipulated parasites. The target mutants were enriched to the desired level within two weeks. We show that our system can also be used for sequential genetic manipulation of parasites carrying the traditionally used selection markers, demonstrate the procedure’s versatility, and show its use in isolating specific genetically manipulated parasites. This novel in vitro selection method increases the number of available selection markers, allowing more extensive genetic manipulation in malaria parasite research.
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Affiliation(s)
- Akira Soga
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
| | - Hironori Bando
- Department of immunoparasitology, Research Institute for Microbial Disease, Osaka University, Yamada-oka, Suita, Osaka, 565-0871, Japan
| | - Mami Ko-Ketsu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
| | - Hirono Masuda-Suganuma
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
| | - Shin-Ichiro Kawazu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
| | - Shinya Fukumoto
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
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17
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Tribensky A, Graf AW, Diehl M, Fleck W, Przyborski JM. Trafficking of PfExp1 to the parasitophorous vacuolar membrane of Plasmodium falciparum is independent of protein folding and the PTEX translocon. Cell Microbiol 2017; 19. [PMID: 27892646 DOI: 10.1111/cmi.12710] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/19/2016] [Accepted: 11/24/2016] [Indexed: 12/13/2022]
Abstract
Having entered the mature human erythrocyte, the malaria parasite survives and propagates within a parasitophorous vacuole, a membrane-bound compartment separating the parasite from the host cell cytosol. The bounding membrane of this vacuole, referred to as the parasitophorous vacuolar membrane (PVM), contains parasite-encoded proteins, but how these membrane proteins are trafficked to the PVM remains unknown. Here, we have studied the trafficking of PfExp1 to the PVM. We find that trafficking of PfExp1 to the PVM is independent of the folding state of the protein and also continues unabated upon inactivation of the PVM translocon Plasmodium Translocon of Exported proteins (PTEX). Our data strongly suggest that the trafficking of membrane proteins to the PVM occurs by as yet unknown mechanism, potentially unique to Plasmodium.
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Affiliation(s)
- Anke Tribensky
- Department of Parasitology, University of Marburg, Marburg, Germany
| | - Andreas W Graf
- Department of Parasitology, University of Marburg, Marburg, Germany
| | - Mathias Diehl
- Department of Parasitology, University of Marburg, Marburg, Germany
| | - Wiebke Fleck
- Department of Parasitology, University of Marburg, Marburg, Germany
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18
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Liu L, Ji X, Li Y, Ji W, Mo T, Ding W, Zhang Q. A mechanistic study of the non-oxidative decarboxylation catalyzed by the radical S-adenosyl-l-methionine enzyme BlsE involved in blasticidin S biosynthesis. Chem Commun (Camb) 2017; 53:8952-8955. [DOI: 10.1039/c7cc04286h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BlsE-catalyzed non-oxidative decarboxylation is initiated by a hydrogen abstraction from a sugar carbon of the substrate cytosylglucuronic acid (CGA).
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Affiliation(s)
- Lei Liu
- College of Life Science & Biotechnology
- Mianyang Normal University
- Mianyang 621000
- P. R. China
- Department of Chemistry
| | - Xinjian Ji
- Department of Chemistry
- Fudan University
- Shanghai
- China
| | - Yongzhen Li
- Department of Chemistry
- Fudan University
- Shanghai
- China
- Medical College of Qinghai University
| | - Wenjuan Ji
- Department of Chemistry
- Fudan University
- Shanghai
- China
| | - Tianlu Mo
- Department of Chemistry
- Fudan University
- Shanghai
- China
| | - Wei Ding
- Department of Chemistry
- Fudan University
- Shanghai
- China
| | - Qi Zhang
- Department of Chemistry
- Fudan University
- Shanghai
- China
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19
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Tran PN, Tate CJ, Ridgway MC, Saliba KJ, Kirk K, Maier AG. Human dihydrofolate reductase influences the sensitivity of the malaria parasite Plasmodium falciparum to ketotifen - A cautionary tale in screening transgenic parasites. Int J Parasitol Drugs Drug Resist 2016; 6:179-183. [PMID: 27705841 PMCID: PMC5050295 DOI: 10.1016/j.ijpddr.2016.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/20/2016] [Accepted: 09/22/2016] [Indexed: 11/24/2022]
Abstract
Ketotifen has recently been reported to inhibit the growth of both asexual and sexual malaria parasites. A parasite transporter, PfgABCG2, has been implicated in its mechanism of action. Human dihydrofolate reductase (hDHFR) is the most commonly used selectable marker to create transgenic Plasmodium falciparum cell lines. Growth assays using transgenic P. falciparum parasites with different selectable markers revealed that the presence of hDHFR rather than the absence of PfgABCG2 is responsible for a shift in the parasite's sensitivity to ketotifen. Employing a range of in vitro assays and liquid chromatography-mass spectrometry we show that ketotifen influences hDHFR activity, but it is not metabolised by the enzyme. Our data also highlights potential pitfalls when functionally characterising transgenic parasites.
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Affiliation(s)
- Phuong N Tran
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Cameron J Tate
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Melanie C Ridgway
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Kevin J Saliba
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia; Medical School, The Australian National University, Canberra, ACT, 2601, Australia
| | - Kiaran Kirk
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Alexander G Maier
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia.
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20
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Targeting Protein Translation in Organelles of the Apicomplexa. Trends Parasitol 2016; 32:953-965. [DOI: 10.1016/j.pt.2016.09.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 09/21/2016] [Accepted: 09/23/2016] [Indexed: 12/15/2022]
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21
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Mutations in the Plasmodium falciparum Cyclic Amine Resistance Locus (PfCARL) Confer Multidrug Resistance. mBio 2016; 7:mBio.00696-16. [PMID: 27381290 PMCID: PMC4958248 DOI: 10.1128/mbio.00696-16] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Mutations in the Plasmodium falciparum cyclic amine resistance locus (PfCARL) are associated with parasite resistance to the imidazolopiperazines, a potent class of novel antimalarial compounds that display both prophylactic and transmission-blocking activity, in addition to activity against blood-stage parasites. Here, we show that pfcarl encodes a protein, with a predicted molecular weight of 153 kDa, that localizes to the cis-Golgi apparatus of the parasite in both asexual and sexual blood stages. Utilizing clustered regularly interspaced short palindromic repeat (CRISPR)-mediated gene introduction of 5 variants (L830V, S1076N/I, V1103L, and I1139K), we demonstrate that mutations in pfcarl are sufficient to generate resistance against the imidazolopiperazines in both asexual and sexual blood-stage parasites. We further determined that the mutant PfCARL protein confers resistance to several structurally unrelated compounds. These data suggest that PfCARL modulates the levels of small-molecule inhibitors that affect Golgi-related processes, such as protein sorting or membrane trafficking, and is therefore an important mechanism of resistance in malaria parasites. Several previous in vitro evolution studies have implicated the Plasmodium falciparum cyclic amine resistance locus (PfCARL) as a potential target of imidazolopiperazines, potent antimalarial compounds with broad activity against different parasite life cycle stages. Given that the imidazolopiperazines are currently being tested in clinical trials, understanding their mechanism of resistance and the cellular processes involved will allow more effective clinical usage.
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Lu J, Tong Y, Pan J, Yang Y, Liu Q, Tan X, Zhao S, Qin L, Chen X. A redesigned CRISPR/Cas9 system for marker-free genome editing in Plasmodium falciparum. Parasit Vectors 2016; 9:198. [PMID: 27066899 PMCID: PMC4828878 DOI: 10.1186/s13071-016-1487-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/01/2016] [Indexed: 12/02/2022] Open
Abstract
Background A highly efficient CRISPR/Cas9-based marker-free genome editing system has been established in Plasmodium falciparum (Pf). However, with the current methods, two drug-selectable markers are needed for episome retention, which may present hurdles for consecutive genome manipulations due to the limited number of available selectable markers. The loading capacity of donor DNA is also unsatisfactory due to the large size of the Cas9 nuclease and sgRNA co-expression system, which limits the size of knock-in DNA fragments. Because of the inefficient end joining (EJ) DNA repair mechanism of Pf, a suicide-rescue approach could be used to address the challenges. Cas9 nuclease and sgRNA were co-expressed from a single plasmid (suicide vector) with one selectable marker, and the donor DNA was ligated into the other plasmid (rescue vector) containing only the ampicillin-resistance gene (AmpR) and a ColEl replication origin (ori). Nonetheless, whether this approach can mediate even the regular gene editing in Pf remains unknown. This study aimed to demonstrate the basic gene editing function of this Cas9-mediated suicide-rescue system. Findings The suicide and rescue vectors were constructed and co-transfected into Pf3D7. This system worked as expected when used to disrupt the Pfset2 gene and to insert a green fluorescent protein-renilla luciferase (gfp-ruc) fusion gene cassette of 3334 base pairs (bp) into the Pf47 locus, demonstrating that the suicide vector actually induced double-strand breaks (DSBs) and that the rescue vector functioned without maintenance via drug selection. Conclusions The adapted marker-free CRISPR/Cas9 system with only a single episome-selectable marker performs well as the current systems for general gene editing which lays a solid foundation for further studies including consecutive gene manipulations and large gene knock-ins. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1487-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Junnan Lu
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Ying Tong
- CAS Lamvac Biotech Co., Ltd, No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Jiaqiang Pan
- CAS Lamvac Biotech Co., Ltd, No. 3 Lanyue Road, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Yijun Yang
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Quan Liu
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Xuefang Tan
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Siting Zhao
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China
| | - Li Qin
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China.
| | - Xiaoping Chen
- Laboratory of Pathogen Biology, State Key Laboratory of Respiratory Disease, Center for Infection and Immunity, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, No. 190 Kaiyuan Avenue, Guangzhou Science Park, Guangzhou, 510530, Guangdong Province, China.
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A semi-automated luminescence based standard membrane feeding assay identifies novel small molecules that inhibit transmission of malaria parasites by mosquitoes. Sci Rep 2015; 5:18704. [PMID: 26687564 PMCID: PMC4685452 DOI: 10.1038/srep18704] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 11/24/2015] [Indexed: 12/27/2022] Open
Abstract
Current first-line treatments for uncomplicated falciparum malaria rapidly clear the asexual stages of the parasite, but do not fully prevent parasite transmission by mosquitoes. The standard membrane feeding assay (SMFA) is the biological gold standard assessment of transmission reducing activity (TRA), but its throughput is limited by the need to determine mosquito infection status by dissection and microscopy. Here we present a novel dissection-free luminescence based SMFA format using a transgenic Plasmodium falciparum reporter parasite without resistance to known antimalarials and therefore unrestricted in its utility in compound screening. Analyses of sixty-five compounds from the Medicines for Malaria Venture validation and malaria boxes identified 37 compounds with high levels of TRA (>80%); different assay modes allowed discrimination between gametocytocidal and downstream modes of action. Comparison of SMFA data to published assay formats for predicting parasite infectivity indicated that individual in vitro screens show substantial numbers of false negatives. These results highlight the importance of the SMFA in the screening pipeline for transmission reducing compounds and present a rapid and objective method. In addition we present sixteen diverse chemical scaffolds from the malaria box that may serve as a starting point for further discovery and development of malaria transmission blocking drugs.
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de Koning-Ward TF, Gilson PR, Crabb BS. Advances in molecular genetic systems in malaria. Nat Rev Microbiol 2015; 13:373-87. [DOI: 10.1038/nrmicro3450] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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DNA repair mechanisms and their biological roles in the malaria parasite Plasmodium falciparum. Microbiol Mol Biol Rev 2015; 78:469-86. [PMID: 25184562 DOI: 10.1128/mmbr.00059-13] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Research into the complex genetic underpinnings of the malaria parasite Plasmodium falciparum is entering a new era with the arrival of site-specific genome engineering. Previously restricted only to model systems but now expanded to most laboratory organisms, and even to humans for experimental gene therapy studies, this technology allows researchers to rapidly generate previously unattainable genetic modifications. This technological advance is dependent on DNA double-strand break repair (DSBR), specifically homologous recombination in the case of Plasmodium. Our understanding of DSBR in malaria parasites, however, is based largely on assumptions and knowledge taken from other model systems, which do not always hold true in Plasmodium. Here we describe the causes of double-strand breaks, the mechanisms of DSBR, and the differences between model systems and P. falciparum. These mechanisms drive basic parasite functions, such as meiosis, antigen diversification, and copy number variation, and allow the parasite to continually evolve in the contexts of host immune pressure and drug selection. Finally, we discuss the new technologies that leverage DSBR mechanisms to accelerate genetic investigations into this global infectious pathogen.
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Matz JM, Kooij TWA. Towards genome-wide experimental genetics in the in vivo malaria model parasite Plasmodium berghei. Pathog Glob Health 2015; 109:46-60. [PMID: 25789828 DOI: 10.1179/2047773215y.0000000006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Plasmodium berghei was identified as a parasite of thicket rats (Grammomys dolichurus) and Anopheles dureni mosquitoes in African highland forests. Successful adaptation to a range of rodent and mosquito species established P. berghei as a malaria model parasite. The introduction of stable transfection technology, permitted classical reverse genetics strategies and thus systematic functional profiling of the gene repertoire. In the past 10 years following the publication of the P. berghei genome sequence, many new tools for experimental genetics approaches have been developed and existing ones have been improved. The infection of mice is the principal limitation towards a genome-wide repository of mutant parasite lines. In the past few years, there have been some promising and most welcome developments that allow rapid selection and isolation of recombinant parasites while simultaneously minimising animal usage. Here, we provide an overview of all the currently available tools and methods.
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27
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Webster WAJ, McFadden GI. From the genome to the phenome: tools to understand the basic biology of Plasmodium falciparum. J Eukaryot Microbiol 2014; 61:655-71. [PMID: 25227912 DOI: 10.1111/jeu.12176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/01/2014] [Accepted: 09/02/2014] [Indexed: 11/30/2022]
Abstract
Malaria plagues one out of every 30 humans and contributes to almost a million deaths, and the problem could worsen. Our current therapeutic options are compromised by emerging resistance by the parasite to our front line drugs. It is thus imperative to better understand the basic biology of the parasite and develop novel drugs to stem this disease. The most facile approach to analyse a gene's function is to remove it from the genome or inhibit its activity. Although genetic manipulation of the human malaria parasite Plasmodium falciparum is a relatively standard procedure, there is no optimal method to perturb genes essential to the intraerythrocytic development cycle--the part of the life cycle that produces the clinical manifestation of malaria. This is a severe impediment to progress because the phenotype we wish to study is exactly the one that is so elusive. In the absence of any utilitarian way to conditionally delete essential genes, we are prevented from investigating the parasite's most vulnerable points. This review aims to focus on the development of tools identifying essential genes of P. falciparum and our ability to elicit phenotypic mutation.
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Affiliation(s)
- Wesley A J Webster
- Centre for Regional and Rural Futures, School of Life and Environmental Sciences, Deakin University, Burwood, 3125, Victoria, Australia; Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Melbourne, 3010, Victoria, Australia
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Ojo KK, Eastman RT, Vidadala R, Zhang Z, Rivas KL, Choi R, Lutz JD, Reid MC, Fox AMW, Hulverson MA, Kennedy M, Isoherranen N, Kim LM, Comess KM, Kempf DJ, Verlinde CLMJ, Su XZ, Kappe SHI, Maly DJ, Fan E, Van Voorhis WC. A specific inhibitor of PfCDPK4 blocks malaria transmission: chemical-genetic validation. J Infect Dis 2014; 209:275-84. [PMID: 24123773 PMCID: PMC3873787 DOI: 10.1093/infdis/jit522] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 06/07/2013] [Indexed: 01/03/2023] Open
Abstract
Malaria parasites are transmitted by mosquitoes, and blocking parasite transmission is critical in reducing or eliminating malaria in endemic regions. Here, we report the pharmacological characterization of a new class of malaria transmission-blocking compounds that acts via the inhibition of Plasmodia CDPK4 enzyme. We demonstrate that these compounds achieved selectivity over mammalian kinases by capitalizing on a small serine gatekeeper residue in the active site of the Plasmodium CDPK4 enzyme. To directly confirm the mechanism of action of these compounds, we generated P. falciparum parasites that express a drug-resistant methionine gatekeeper (S147 M) CDPK4 mutant. Mutant parasites showed a shift in exflagellation EC50 relative to the wild-type strains in the presence of compound 1294, providing chemical-genetic evidence that CDPK4 is the target of the compound. Pharmacokinetic analyses suggest that coformulation of this transmission-blocking agent with asexual stage antimalarials such as artemisinin combination therapy (ACT) is a promising option for drug delivery that may reduce transmission of malaria including drug-resistant strains. Ongoing studies include refining the compounds to improve efficacy and toxicological properties for efficient blocking of malaria transmission.
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Affiliation(s)
- Kayode K. Ojo
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Richard T. Eastman
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | | | | | - Kasey L. Rivas
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Ryan Choi
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Justin D. Lutz
- Department of Pharmaceutics, University of Washington, Seattle
| | - Molly C. Reid
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Anna M. W. Fox
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Matthew A. Hulverson
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
| | - Mark Kennedy
- Seattle Biomedical Research Institute, Washington
| | | | - Laura M. Kim
- Global Pharmaceutical R&D, AbbVie, North Chicago, Illinois
| | | | - Dale J. Kempf
- Global Pharmaceutical R&D, AbbVie, North Chicago, Illinois
| | | | - Xin-zhuan Su
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | | | | | | | - Wesley C. Van Voorhis
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle
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Wagner JC, Goldfless SJ, Ganesan SM, Lee MCS, Fidock DA, Niles JC. An integrated strategy for efficient vector construction and multi-gene expression in Plasmodium falciparum. Malar J 2013; 12:373. [PMID: 24160265 PMCID: PMC3842810 DOI: 10.1186/1475-2875-12-373] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 10/22/2013] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The construction of plasmid vectors for transgene expression in the malaria parasite, Plasmodium falciparum, presents major technical hurdles. Traditional molecular cloning by restriction and ligation often yields deletions and re-arrangements when assembling low-complexity (A + T)-rich parasite DNA. Furthermore, the use of large 5'- and 3'- untranslated regions of DNA sequence (UTRs) to drive transgene transcription limits the number of expression cassettes that can be incorporated into plasmid vectors. METHODS To address these challenges, two high fidelity cloning strategies, namely yeast homologous recombination and the Gibson assembly method, were evaluated for constructing P. falciparum vectors. Additionally, some general rules for reliably using the viral 2A-like peptide to express multiple proteins from a single expression cassette while preserving their proper trafficking to various subcellular compartments were assessed. RESULTS Yeast homologous recombination and Gibson assembly were found to be effective strategies for successfully constructing P. falciparum plasmid vectors. Using these cloning methods, a validated family of expression vectors that provide a flexible starting point for user-specific applications was created. These vectors are also compatible with traditional cloning by restriction and ligation, and contain useful combinations of commonly used features for enhancing plasmid segregation and site-specific integration in P. falciparum. Additionally, application of a 2A-like peptide for the synthesis of multiple proteins from a single expression cassette, and some rules for combinatorially directing proteins to discrete subcellular compartments were established. CONCLUSIONS A set of freely available, sequence-verified and functionally validated parts that offer greater flexibility for constructing P. falciparum vectors having expanded expression capacity is provided.
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Affiliation(s)
- Jeffrey C Wagner
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Stephen J Goldfless
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Suresh M Ganesan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Marcus CS Lee
- Department of Microbiology and Immunology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
- Division of Infectious Diseases, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Feng J, Wu J, Dai N, Lin S, Xu HH, Deng Z, He X. Discovery and characterization of BlsE, a radical S-adenosyl-L-methionine decarboxylase involved in the blasticidin S biosynthetic pathway. PLoS One 2013; 8:e68545. [PMID: 23874663 PMCID: PMC3715490 DOI: 10.1371/journal.pone.0068545] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 05/30/2013] [Indexed: 11/19/2022] Open
Abstract
BlsE, a predicted radical S-adenosyl-L-methionine (SAM) protein, was anaerobically purified and reconstituted in vitro to study its function in the blasticidin S biosynthetic pathway. The putative role of BlsE was elucidated based on bioinformatics analysis, genetic inactivation and biochemical characterization. Biochemical results showed that BlsE is a SAM-dependent radical enzyme that utilizes cytosylglucuronic acid, the accumulated intermediate metabolite in blsE mutant, as substrate and catalyzes decarboxylation at the C5 position of the glucoside residue to yield cytosylarabinopyranose. Additionally, we report the purification and reconstitution of BlsE, characterization of its [4Fe-4S] cluster using UV-vis and electron paramagnetic resonance (EPR) spectroscopic analysis, and investigation of the ability of flavodoxin (Fld), flavodoxin reductase (Fpr) and NADPH to reduce the [4Fe-4S](2+) cluster. Mutagenesis studies demonstrated that Cys31, Cys35, Cys38 in the C×××C×MC motif and Gly73, Gly74, Glu75, Pro76 in the GGEP motif were crucial amino acids for BlsE activity while mutation of Met37 had little effect on its function. Our results indicate that BlsE represents a typical [4Fe-4S]-containing radical SAM enzyme and it catalyzes decarboxylation in blasticidin S biosynthesis.
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Affiliation(s)
- Jun Feng
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jun Wu
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Nan Dai
- New England Biolabs, Inc., Research Department, Ipswich, Massachusetts, United States of America
| | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - H. Howard Xu
- Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, United States of America
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xinyi He
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail:
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Augagneur Y, Jaubert L, Schiavoni M, Pachikara N, Garg A, Usmani-Brown S, Wesolowski D, Zeller S, Ghosal A, Cornillot E, Said HM, Kumar P, Altman S, Ben Mamoun C. Identification and functional analysis of the primary pantothenate transporter, PfPAT, of the human malaria parasite Plasmodium falciparum. J Biol Chem 2013; 288:20558-67. [PMID: 23729665 DOI: 10.1074/jbc.m113.482992] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human malaria parasite Plasmodium falciparum is absolutely dependent on the acquisition of host pantothenate for its development within human erythrocytes. Although the biochemical properties of this transport have been characterized, the molecular identity of the parasite-encoded pantothenate transporter remains unknown. Here we report the identification and functional characterization of the first protozoan pantothenate transporter, PfPAT, from P. falciparum. We show using cell biological, biochemical, and genetic analyses that this transporter is localized to the parasite plasma membrane and plays an essential role in parasite intraerythrocytic development. We have targeted PfPAT to the yeast plasma membrane and showed that the transporter complements the growth defect of the yeast fen2Δ pantothenate transporter-deficient mutant and mediates the entry of the fungicide drug, fenpropimorph. Our studies in P. falciparum revealed that fenpropimorph inhibits the intraerythrocytic development of both chloroquine- and pyrimethamine-resistant P. falciparum strains with potency equal or better than that of currently available pantothenate analogs. The essential function of PfPAT and its ability to deliver both pantothenate and fenpropimorph makes it an attractive target for the development and delivery of new classes of antimalarial drugs.
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Affiliation(s)
- Yoann Augagneur
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Molina-Cruz A, Garver LS, Alabaster A, Bangiolo L, Haile A, Winikor J, Ortega C, van Schaijk BCL, Sauerwein RW, Taylor-Salmon E, Barillas-Mury C. The human malaria parasite Pfs47 gene mediates evasion of the mosquito immune system. Science 2013; 340:984-7. [PMID: 23661646 DOI: 10.1126/science.1235264] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Plasmodium falciparum transmission by Anopheles gambiae mosquitoes is remarkably efficient, resulting in a very high prevalence of human malaria infection in sub-Saharan Africa. A combination of genetic mapping, linkage group selection, and functional genomics was used to identify Pfs47 as a P. falciparum gene that allows the parasite to infect A. gambiae without activating the mosquito immune system. Disruption of Pfs47 greatly reduced parasite survival in the mosquito, and this phenotype could be reverted by genetic complementation of the parasite or by disruption of the mosquito complement-like system. Pfs47 suppresses midgut nitration responses that are critical to activate the complement-like system. We provide direct experimental evidence that immune evasion mediated by Pfs47 is critical for efficient human malaria transmission by A. gambiae.
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Affiliation(s)
- Alvaro Molina-Cruz
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA
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Transposon mutagenesis identifies genes essential for Plasmodium falciparum gametocytogenesis. Proc Natl Acad Sci U S A 2013; 110:E1676-84. [PMID: 23572579 DOI: 10.1073/pnas.1217712110] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Gametocytes are essential for Plasmodium transmission, but little is known about the mechanisms that lead to their formation. Using piggyBac transposon-mediated insertional mutagenesis, we screened for parasites that no longer form mature gametocytes, which led to the isolation of 29 clones (insertional gametocyte-deficient mutants) that fail to form mature gametocytes. Additional analysis revealed 16 genes putatively responsible for the loss of gametocytogenesis, none of which has been previously implicated in gametocytogenesis. Transcriptional profiling and detection of an early stage gametocyte antigen determined that a subset of these mutants arrests development at stage I or in early stage II gametocytes, likely representing genes involved in gametocyte maturation. The remaining mutants seem to arrest before formation of stage I gametocytes and may represent genes involved in commitment to the gametocyte lineage.
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Roberts RN, Schlarman MS, Kariuki MM, Lacrue AN, Ou R, Beerntsen BT. Expression profile of the Plasmodium falciparum intra-erythrocytic stage protein, PF3D7_1363700. Malar J 2013; 12:66. [PMID: 23418676 PMCID: PMC3637116 DOI: 10.1186/1475-2875-12-66] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 02/12/2013] [Indexed: 11/30/2022] Open
Abstract
Background Efforts to control malaria are demanding due to drug-resistant parasites, insecticide-resistant mosquitoes and poor health infrastructure in malaria-endemic countries. Therefore, the research and development of additional malaria control methods are crucial. For host-parasite interactions, surface antigens and secreted proteins are likely to be involved in infectivity and invasion of host tissues and therefore can be effective targets for control by vaccines, drug therapy, or novel mosquito control methods. In an effort to identify and characterize genes that may have a role in host-parasite interaction, this study describes the expression profile of Plasmodium falciparum PF3D7_1363700. Methods A P. falciparum gene, PF3D7_1363700, was identified by a search of the annotated Plasmodium genome database. Protein alignments of PF3D7_1363700 orthologues from various Plasmodium species were performed to demonstrate protein similarity. Transcript expression profiles of PF3D7_1363700 were determined via reverse-transcriptase PCR and protein expression was investigated by immunofluorescence assays, western blot analysis and green fluorescent trafficking studies. Results The PF3D7_1363700 protein demonstrates significant similarity with orthologues in other Plasmodium species and appears to be unique to Apicomplexans. The PF3D7_1363700 transcription profile demonstrated expression during the intra-erythrocytic, oocyst sporozoite, and salivary gland sporozoite stages while the PF3D7_1363700 protein was only detected during the intra-erythrocytic stages. Conclusions This research utilized an in silico approach to identify a well-conserved protein known as PF3D7_1363700. By molecular, biochemical and cellular analyses, PF3D7_1363700 was discovered to be an intra-erythrocytic-specific stage protein that is unique to Apicomplexans.
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Affiliation(s)
- Renee N Roberts
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
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35
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Streptomyces lividans blasticidin S deaminase and its application in engineering a blasticidin S-producing strain for ease of genetic manipulation. Appl Environ Microbiol 2013; 79:2349-57. [PMID: 23377931 DOI: 10.1128/aem.03254-12] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Blasticidin S is a peptidyl nucleoside antibiotic produced by Streptomyces griseochromogenes that exhibits strong fungicidal activity. To circumvent an effective DNA uptake barrier system in the native producer and investigate its biosynthesis in vivo, the blasticidin S biosynthetic gene cluster (bls) was engrafted to the chromosome of Streptomyces lividans. However, the resulting mutant, LL2, produced the inactive deaminohydroxyblasticidin S instead of blasticidin S. Subsequently, a blasticidin S deaminase (SLBSD, for S. lividans blasticidin S deaminase) was identified in S. lividans and shown to govern this in vivo conversion. Purified SLBSD was found to be capable of transforming blasticidin S to deaminohydroxyblasticidin S in vitro. It also catalyzed deamination of the cytosine moiety of cytosylglucuronic acid, an intermediate in blasticidin S biosynthesis. Disruption of the SLBSD gene in S. lividans LL2 led to successful production of active blasticidin S in the resultant mutant, S. lividans WJ2. To demonstrate the easy manipulation of the blasticidin S biosynthetic gene cluster, blsE, blsF, and blsL, encoding a predicted radical S-adenosylmethionine (SAM) protein, an unknown protein, and a guanidino methyltransferase, were individually inactivated to access their role in blasticidin S biosynthesis.
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Eksi S, Morahan BJ, Haile Y, Furuya T, Jiang H, Ali O, Xu H, Kiattibutr K, Suri A, Czesny B, Adeyemo A, Myers TG, Sattabongkot J, Su XZ, Williamson KC. Plasmodium falciparum gametocyte development 1 (Pfgdv1) and gametocytogenesis early gene identification and commitment to sexual development. PLoS Pathog 2012; 8:e1002964. [PMID: 23093935 PMCID: PMC3475683 DOI: 10.1371/journal.ppat.1002964] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 08/27/2012] [Indexed: 12/13/2022] Open
Abstract
Malaria transmission requires the production of male and female gametocytes in the human host followed by fertilization and sporogonic development in the mosquito midgut. Although essential for the spread of malaria through the population, little is known about the initiation of gametocytogenesis in vitro or in vivo. Using a gametocyte-defective parasite line and genetic complementation, we show that Plasmodium falciparumgametocyte development 1 gene (Pfgdv1), encoding a peri-nuclear protein, is critical for early sexual differentiation. Transcriptional analysis of Pfgdv1 negative and positive parasite lines identified a set of gametocytogenesis early genes (Pfge) that were significantly down-regulated (>10 fold) in the absence of Pfgdv1 and expression was restored after Pfgdv1 complementation. Progressive accumulation of Pfge transcripts during successive rounds of asexual replication in synchronized cultures suggests that gametocytes are induced continuously during asexual growth. Comparison of Pfge gene transcriptional profiles in patient samples divided the genes into two groups differing in their expression in mature circulating gametocytes and providing candidates to evaluate gametocyte induction and maturation separately in vivo. The expression profile of one of the early gametocyte specific genes, Pfge1, correlated significantly with asexual parasitemia, which is consistent with the ongoing induction of gametocytogenesis during asexual growth observed in vitro and reinforces the need for sustained transmission-blocking strategies to eliminate malaria. As malaria control efforts move toward eradication it becomes increasingly important to develop interventions that block transmission. Consequently, advances are needed in our understanding of the production of gametocytes, which are required to transmit the disease. This report provides a first view of the initial stages of gametocytogenesis in vitro and in vivo and demonstrates that during each asexual replication cycle a subpopulation of parasites convert to gametocyte development providing a long transmission window. We also identify a gene that is critical for gametocyte production, P. falciparumgametocyte development 1 (Pfgdv1) and a set of genes specifically expressed during early gametocytogenesis in P. falciparum (Pfge genes). The expression profile and peri-nuclear location of Pfgdv1 in a subpopulation of schizonts is consistent with a role in an early step in gametocytogenesis. The RNA levels of Pfgdv1 and the Pfge genes accumulated gradually over several asexual cycles in vitro suggesting ongoing gametocyte formation during asexual growth. The further evaluation of these genes in a cohort of malaria infected patients indicated they are good candidates for markers to distinguish ring stage parasites committed to gametocyte production from circulating mature gametocytes, allowing direct analysis of the initiation of sexual differentiation in vivo.
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Affiliation(s)
- Saliha Eksi
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
| | - Belinda J. Morahan
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Yoseph Haile
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
| | - Tetsuya Furuya
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Hongying Jiang
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Omar Ali
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
| | - Huichun Xu
- Center for Research on Genomics and Global Health, Inherited Disease Research Branch, National Human Genomics Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kirakorn Kiattibutr
- Department of Entomology, U.S. Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Amreena Suri
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
| | - Beata Czesny
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
| | - Adebowale Adeyemo
- Center for Research on Genomics and Global Health, Inherited Disease Research Branch, National Human Genomics Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Timothy G. Myers
- Genomic Technologies Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jetsumon Sattabongkot
- Department of Entomology, U.S. Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Xin-zhuan Su
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kim C. Williamson
- Department of Biology, Loyola University Chicago, Chicago, Illinois, United States of America
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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Hagen J, Lee EF, Fairlie WD, Kalinna BH. Functional genomics approaches in parasitic helminths. Parasite Immunol 2012; 34:163-82. [PMID: 21711361 DOI: 10.1111/j.1365-3024.2011.01306.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As research on parasitic helminths is moving into the post-genomic era, an enormous effort is directed towards deciphering gene function and to achieve gene annotation. The sequences that are available in public databases undoubtedly hold information that can be utilized for new interventions and control but the exploitation of these resources has until recently remained difficult. Only now, with the emergence of methods to genetically manipulate and transform parasitic worms will it be possible to gain a comprehensive understanding of the molecular mechanisms involved in nutrition, metabolism, developmental switches/maturation and interaction with the host immune system. This review focuses on functional genomics approaches in parasitic helminths that are currently used, to highlight potential applications of these technologies in the areas of cell biology, systems biology and immunobiology of parasitic helminths.
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Affiliation(s)
- J Hagen
- Department of Veterinary Science, Centre for Animal Biotechnology, The University of Melbourne, Vic., Australia
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Abstract
Genetic manipulation of Plasmodium falciparum remains very challenging, mainly due to the parasite genome's high A/T-richness and low transfection efficiency. This chapter includes methods for generating transient and stable transfections by electroporation, allelic replacement with tagged genes, gene deletion, and the analysis of all the above.
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Somsak V, Uthaipibull C, Prommana P, Srichairatanakool S, Yuthavong Y, Kamchonwongpaisan S. Transgenic Plasmodium parasites stably expressing Plasmodium vivax dihydrofolate reductase-thymidylate synthase as in vitro and in vivo models for antifolate screening. Malar J 2011; 10:291. [PMID: 21981896 PMCID: PMC3198988 DOI: 10.1186/1475-2875-10-291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 10/07/2011] [Indexed: 11/12/2022] Open
Abstract
Background Plasmodium vivax is the most prevalent cause of human malaria in tropical regions outside the African continent. The lack of a routine continuous in vitro culture of this parasite makes it difficult to develop specific drugs for this disease. To facilitate the development of anti-P. vivax drugs, bacterial and yeast surrogate models expressing the validated P. vivax target dihydrofolate reductase-thymidylate synthase (DHFR-TS) have been generated; however, they can only be used as primary screening models because of significant differences in enzyme expression level and in vivo drug metabolism between the surrogate models and P. vivax parasites. Methods Plasmodium falciparum and Plasmodium berghei parasites were transfected with DNA constructs bearing P. vivax dhfr-ts pyrimethamine sensitive (wild-type) and pyrimethamine resistant (mutant) alleles. Double crossover homologous recombination was used to replace the endogenous dhfr-ts of P. falciparum and P. berghei parasites with P. vivax homologous genes. The integration of Pvdhfr-ts genes via allelic replacement was verified by Southern analysis and the transgenic parasites lines validated as models by standard drug screening assays. Results Transgenic P. falciparum and P. berghei lines stably expressing PvDHFR-TS replacing the endogenous parasite DHFR-TS were obtained. Anti-malarial drug screening assays showed that transgenic parasites expressing wild-type PvDHFR-TS were pyrimethamine-sensitive, whereas transgenic parasites expressing mutant PvDHFR-TS were pyrimethamine-resistant. The growth and sensitivity to other types of anti-malarial drugs in the transgenic parasites were otherwise indistinguishable from the parental parasites. Conclusion With the permanent integration of Pvdhfr-ts gene in the genome, the transgenic Plasmodium lines expressing PvDHFR-TS are genetically stable and will be useful for screening anti-P. vivax compounds targeting PvDHFR-TS. A similar approach could be used to generate transgenic models specific for other targets of interest, thus facilitating the development of anti-P. vivax drugs in general.
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Affiliation(s)
- Voravuth Somsak
- Protein-Ligand Engineering and Molecular Biology Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, Pathumthani 12120, Thailand
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Limenitakis J, Soldati-Favre D. Functional genetics in Apicomplexa: potentials and limits. FEBS Lett 2011; 585:1579-88. [PMID: 21557944 DOI: 10.1016/j.febslet.2011.05.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/02/2011] [Accepted: 05/03/2011] [Indexed: 01/15/2023]
Abstract
The Apicomplexans are obligate intracellular protozoan parasites and the causative agents of severe diseases in humans and animals. Although complete genome sequences are available since many years and for several parasites, they are replete with putative genes of unassigned function. Forward and reverse genetic approaches are limited only to a few Apicomplexans that can either be propagated in vitro or in a convenient animal model. This review will compare and contrast the most recent strategies developed for the genetic manipulation of Plasmodium falciparum, Plasmodium berghei and Toxoplasma gondii that have taken advantage of the intrinsic features of their respective genomes. Efforts towards the improvement of the transfection efficiencies in malaria parasites, the development of approaches to study essential genes and the elaboration of high-throughput methods for the identification of gene function will be discussed.
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Affiliation(s)
- Julien Limenitakis
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, Geneva, Switzerland.
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Yeast dihydroorotate dehydrogenase as a new selectable marker for Plasmodium falciparum transfection. Mol Biochem Parasitol 2011; 177:29-34. [PMID: 21251930 DOI: 10.1016/j.molbiopara.2011.01.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 12/29/2010] [Accepted: 01/06/2011] [Indexed: 11/22/2022]
Abstract
Genetic manipulation of Plasmodium falciparum in culture through transfection has provided numerous insights into the molecular and cell biology of this parasite. The procedure is rather cumbersome, and is limited by the number of drug-resistant markers that can be used for selecting transfected parasites. Here we report a new selectable marker that could allow multiple transfections. We have taken advantage of our finding that a critical function of the mitochondrial electron transport chain (mtETC) in the erythrocytic stages of P. falciparum is the regeneration of ubiquinone as co-substrate of dihydroorotate dehydrogenase (DHODH), and that transgenic P. falciparum expressing ubiquinone-independent DHODH from yeast (yDHODH) are resistant to all mtETC inhibitors. We assessed the possibility of using yDHODH as a positive selectable marker for transfections of P. falciparum, including its use in gene disruption strategies. We constructed a transfection vector designed for gene disruption, termed pUF-1, containing the yDHODH gene as the positive selection marker in combination with a previously described fused yeast cytosine deaminase-uracil phosphoribosyl transferase gene as a negative selection marker. Transfection of the D10 strain followed by selection with atovaquone yielded positively selected parasites containing the plasmid, demonstrating that yDHODH can be used as a selective marker. Atovaquone, however, could not be used for such selection with the Dd2 strain of P. falciparum. On the other hand, we demonstrated that yDHODH transgenic parasites could be selected in both strains by Plasmodium DHODH-specific triazolopyrimidine-based inhibitors. Thus, selection with DHODH inhibitors was superior in that it successfully selected transgenic Dd2 parasites, as well as yielded transgenic parasites after a shorter period of selection. As a proof of concept, we have successfully disrupted the type II vacuolar proton-pumping pyrophosphatase gene (PfVP2) in P. falciparum by double crossover recombination, showing that this gene is not essential for the survival of blood stage parasites.
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Anderson T, Nkhoma S, Ecker A, Fidock D. How can we identify parasite genes that underlie antimalarial drug resistance? Pharmacogenomics 2011; 12:59-85. [PMID: 21174623 PMCID: PMC3148835 DOI: 10.2217/pgs.10.165] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
This article outlines genome-scale approaches that can be used to identify mutations in malaria (Plasmodium) parasites that underlie drug resistance and contribute to treatment failure. These approaches include genetic mapping by linkage or genome-wide association studies, drug selection and characterization of resistant mutants, and the identification of genome regions under strong recent selection. While these genomic approaches can identify candidate resistance loci, genetic manipulation is needed to demonstrate causality. We therefore also describe the growing arsenal of available transfection approaches for direct incrimination of mutations suspected to play a role in resistance. Our intention is both to review past progress and highlight promising approaches for future investigations.
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Affiliation(s)
- Tim Anderson
- Department of Genetics, Southwest Foundation for Biomedical Research, San Antonio, TX 78245, USA.
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van Schaijk BCL, Vos MW, Janse CJ, Sauerwein RW, Khan SM. Removal of heterologous sequences from Plasmodium falciparum mutants using FLPe-recombinase. PLoS One 2010; 5:e15121. [PMID: 21152048 PMCID: PMC2994908 DOI: 10.1371/journal.pone.0015121] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2010] [Accepted: 10/22/2010] [Indexed: 01/23/2023] Open
Abstract
Genetically-modified mutants are now indispensable Plasmodium gene-function reagents, which are also being pursued as genetically attenuated parasite vaccines. Currently, the generation of transgenic malaria-parasites requires the use of drug-resistance markers. Here we present the development of an FRT/FLP-recombinase system that enables the generation of transgenic parasites free of resistance genes. We demonstrate in the human malaria parasite, P. falciparum, the complete and efficient removal of the introduced resistance gene. We targeted two neighbouring genes, p52 and p36, using a construct that has a selectable marker cassette flanked by FRT-sequences. This permitted the subsequent removal of the selectable marker cassette by transient transfection of a plasmid that expressed a 37°C thermostable and enhanced FLP-recombinase. This method of removing heterologous DNA sequences from the genome opens up new possibilities in Plasmodium research to sequentially target multiple genes and for using genetically-modified parasites as live, attenuated malaria vaccines.
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Affiliation(s)
- Ben C. L. van Schaijk
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
- * E-mail: ) (BCLvS); (SMK)
| | - Martijn W. Vos
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Chris J. Janse
- Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands
| | - Robert W. Sauerwein
- Department of Medical Microbiology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Shahid M. Khan
- Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands
- * E-mail: ) (BCLvS); (SMK)
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Reininger L, Wilkes JM, Bourgade H, Miranda-Saavedra D, Doerig C. An essential Aurora-related kinase transiently associates with spindle pole bodies during Plasmodium falciparum erythrocytic schizogony. Mol Microbiol 2010; 79:205-21. [PMID: 21166904 PMCID: PMC3025120 DOI: 10.1111/j.1365-2958.2010.07442.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Aurora kinases compose a family of conserved Ser/Thr protein kinases playing essential roles in eukaryotic cell division. To date, Aurora homologues remain uncharacterized in the protozoan phylum Apicomplexa. In malaria parasites, the characterization of Aurora kinases may help understand the cell cycle control during erythrocytic schizogony where asynchronous nuclear divisions occur. In this study, we revisited the kinome of Plasmodium falciparum and identified three Aurora-related kinases, Pfark-1, -2, -3. Among these, Pfark-1 is highly conserved in malaria parasites and also appears to be conserved across Apicomplexa. By tagging the endogenous Pfark-1 gene with the green fluorescent protein (GFP) in live parasites, we show that the Pfark-1–GFP protein forms paired dots associated with only a subset of nuclei within individual schizonts. Immunofluorescence analysis using an anti-α-tubulin antibody strongly suggests a recruitment of Pfark-1 at duplicated spindle pole bodies at the entry of the M phase of the cell cycle. Unsuccessful attempts at disrupting the Pfark-1 gene with a knockout construct further indicate that Pfark-1 is required for parasite growth in red blood cells. Our study provides new insights into the cell cycle control of malaria parasites and reports the importance of Aurora kinases as potential targets for new antimalarials.
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Affiliation(s)
- Luc Reininger
- INSERM-EPFL Joint Laboratory, Global Health Institute, EPFL-SV-GHI, Station 19, CH-1015 Lausanne, Switzerland.
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Valderramos SG, Scanfeld D, Uhlemann AC, Fidock DA, Krishna S. Investigations into the role of the Plasmodium falciparum SERCA (PfATP6) L263E mutation in artemisinin action and resistance. Antimicrob Agents Chemother 2010; 54:3842-52. [PMID: 20566762 PMCID: PMC2935017 DOI: 10.1128/aac.00121-10] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 02/17/2010] [Accepted: 06/07/2010] [Indexed: 11/20/2022] Open
Abstract
Artemisinin-based combination therapies (ACTs) are highly effective for the treatment of Plasmodium falciparum malaria, yet their sustained efficacy is threatened by the potential spread of parasite resistance. Recent studies have provided evidence that artemisinins can inhibit the function of PfATP6, the P. falciparum ortholog of the ER calcium pump SERCA, when expressed in Xenopus laevis oocytes. Inhibition was significantly reduced in an L263E variant, which introduced the mammalian residue into a putative drug-binding pocket. To test the hypothesis that this single mutation could decrease P. falciparum susceptibility to artemisinins, we implemented an allelic-exchange strategy to replace the wild-type pfatp6 allele by a variant allele encoding L263E. Transfected P. falciparum clones were screened by PCR analysis for disruption of the endogenous locus and introduction of the mutant L263E allele under the transcriptional control of a calmodulin promoter. Expression of the mutant allele was demonstrated by reverse transcriptase (RT) PCR and verified by sequence analysis. Parasite clones expressing wild-type or L263E variant PfATP6 showed no significant difference in 50% inhibitory concentrations (IC(50)s) for artemisinin or its derivatives dihydroartemisinin and artesunate. Nonetheless, hierarchical clustering analysis revealed a trend toward reduced susceptibility that neared significance (artemisinin, P approximately = 0.1; dihydroartemisinin, P = 0.053 and P = 0.085; and artesunate, P = 0.082 and P = 0.162 for the D10 and 7G8 lines, respectively). Notable differences in the distribution of normalized IC(50)s provided evidence of decreased responsiveness to artemisinin and dihydroartemisinin (P = 0.02 for the D10 and 7G8 lines), but not to artesunate in parasites expressing mutant PfATP6.
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Affiliation(s)
- Stephanie Gaw Valderramos
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York 10032, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, Division of Cellular and Molecular Medicine, Centre for Infection, St. George's University of London, London, SW17 ORE, United Kingdom, Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York 10032, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032
| | - Daniel Scanfeld
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York 10032, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, Division of Cellular and Molecular Medicine, Centre for Infection, St. George's University of London, London, SW17 ORE, United Kingdom, Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York 10032, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032
| | - Anne-Catrin Uhlemann
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York 10032, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, Division of Cellular and Molecular Medicine, Centre for Infection, St. George's University of London, London, SW17 ORE, United Kingdom, Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York 10032, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032
| | - David A. Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York 10032, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, Division of Cellular and Molecular Medicine, Centre for Infection, St. George's University of London, London, SW17 ORE, United Kingdom, Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York 10032, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032
| | - Sanjeev Krishna
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York 10032, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, Division of Cellular and Molecular Medicine, Centre for Infection, St. George's University of London, London, SW17 ORE, United Kingdom, Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York 10032, New York Presbyterian Hospital, Columbia University Medical Center, New York, New York 10032
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Goldberg DE, Janse CJ, Cowman AF, Waters AP. Has the time come for us to complement our malaria parasites? Trends Parasitol 2010; 27:1-2. [PMID: 20667784 DOI: 10.1016/j.pt.2010.06.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 06/24/2010] [Accepted: 06/30/2010] [Indexed: 10/19/2022]
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Wilson DW, Crabb BS, Beeson JG. Development of fluorescent Plasmodium falciparum for in vitro growth inhibition assays. Malar J 2010; 9:152. [PMID: 20525251 PMCID: PMC2891815 DOI: 10.1186/1475-2875-9-152] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 06/03/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Plasmodium falciparum in vitro growth inhibition assays are widely used to evaluate and quantify the functional activity of acquired and vaccine-induced antibodies and the anti-malarial activity of known drugs and novel compounds. However, several constraints have limited the use of these assays in large-scale population studies, vaccine trials and compound screening for drug discovery and development. METHODS The D10 P. falciparum line was transfected to express green fluorescent protein (GFP). In vitro growth inhibition assays were performed over one or two cycles of P. falciparum asexual replication using inhibitory polyclonal antibodies raised in rabbits, an inhibitory monoclonal antibody, human serum samples, and anti-malarials. Parasitaemia was evaluated by microscopy and flow cytometry. RESULTS Transfected parasites expressed GFP throughout all asexual stages and were clearly detectable by flow cytometry and fluorescence microscopy. Measurement of parasite growth inhibition was the same when determined by detection of GFP fluorescence or staining with ethidium bromide. There was no difference in the inhibitory activity of samples when tested against the transfected parasites compared to the parental line. The level of fluorescence of GFP-expressing parasites increased throughout the course of asexual development. Among ring-stages, GFP-fluorescent parasites were readily separated from uninfected erythrocytes by flow cytometry, whereas this was less clear using ethidium bromide staining. Inhibition by serum and antibody samples was consistently higher when tested over two cycles of growth compared to one, and when using a 1 in 10 sample dilution compared to 1 in 20, but there was no difference detected when using a different starting parasitaemia to set-up growth assays. Flow cytometry based measurements of parasitaemia proved more reproducible than microscopy counts. CONCLUSIONS Flow cytometry based assays using GFP-fluorescent parasites proved sensitive and highly reproducible for quantifying the growth-inhibitory activity of antibodies and anti-malarials, with superior reproducibility to light microscopy, and are suitable for high-throughput applications.
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Affiliation(s)
- Danny W Wilson
- Infection and Immunity Division, the Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria, 3050, Australia
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Külzer S, Rug M, Brinkmann K, Cannon P, Cowman A, Lingelbach K, Blatch GL, Maier AG, Przyborski JM. Parasite-encoded Hsp40 proteins define novel mobile structures in the cytosol of the P. falciparum-infected erythrocyte. Cell Microbiol 2010; 12:1398-420. [DOI: 10.1111/j.1462-5822.2010.01477.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lisk G, Pain M, Sellers M, Gurnev PA, Pillai AD, Bezrukov SM, Desai SA. Altered plasmodial surface anion channel activity and in vitro resistance to permeating antimalarial compounds. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:1679-88. [PMID: 20451492 DOI: 10.1016/j.bbamem.2010.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Revised: 04/21/2010] [Accepted: 04/26/2010] [Indexed: 11/26/2022]
Abstract
Erythrocytes infected with malaria parasites have increased permeability to various solutes. These changes may be mediated by an unusual small conductance ion channel known as the plasmodial surface anion channel (PSAC). While channel activity benefits the parasite by permitting nutrient acquisition, it can also be detrimental because water-soluble antimalarials may more readily access their parasite targets via this channel. Recently, two such toxins, blasticidin S and leupeptin, were used to select mutant parasites with altered PSAC activities, suggesting acquired resistance via reduced channel-mediated toxin uptake. Surprisingly, although these toxins have similar structures and charge, we now show that reduced permeability of one does not protect the intracellular parasite from the other. Leupeptin accumulation in the blasticidin S-resistant mutant was relatively preserved, consistent with retained in vitro susceptibility to leupeptin. Subsequent in vitro selection with both toxins generated a double mutant parasite having additional changes in PSAC, implicating an antimalarial resistance mechanism for water-soluble drugs requiring channel-mediated uptake at the erythrocyte membrane. Characterization of these mutants revealed a single conserved channel on each mutant, albeit with distinct gating properties. These findings are consistent with a shared channel that mediates uptake of ions, nutrients and toxins. This channel's gating and selectivity properties can be modified in response to in vitro selective pressure.
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Affiliation(s)
- Godfrey Lisk
- The Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852, USA
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Transfection systems for Babesia bovis: A review of methods for the transient and stable expression of exogenous genes. Vet Parasitol 2010; 167:205-15. [DOI: 10.1016/j.vetpar.2009.09.022] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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