1
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Blanco CM, de Souza HADS, Martins PDC, Fabbri C, Souza FSD, Lima-Junior JDC, Lopes SCP, Pratt-Riccio LR, Daniel-Ribeiro CT, Totino PRR. Profile of metacaspase gene expression in Plasmodium vivax field isolates from the Brazilian Amazon. Mol Biol Rep 2024; 51:594. [PMID: 38683374 PMCID: PMC11058907 DOI: 10.1007/s11033-024-09538-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 04/09/2024] [Indexed: 05/01/2024]
Abstract
BACKGROUND Metacaspases comprise a family of cysteine proteases implicated in both cell death and cell differentiation of protists that has been considered a potential drug target for protozoan parasites. However, the biology of metacaspases in Plasmodium vivax - the second most prevalent and most widespread human malaria parasite worldwide, whose occurrence of chemoresistance has been reported in many endemic countries, remains largely unexplored. Therefore, the present study aimed to address, for the first time, the expression pattern of metacaspases in P. vivax parasites. METHODS AND RESULTS P. vivax blood-stage parasites were obtained from malaria patients in the Brazilian Amazon and the expression of the three putative P. vivax metacaspases (PvMCA1-3) was detected in all isolates by quantitative PCR assay. Of note, the expression levels of each PvMCA varied noticeably across isolates, which presented different frequencies of parasite forms, supporting that PvMCAs may be expressed in a stage-specific manner as previously shown in P. falciparum. CONCLUSION The detection of metacaspases in P. vivax blood-stage parasites reported herein, allows the inclusion of these proteases as a potential candidate drug target for vivax malaria, while further investigations are still required to evaluate the activity, role and essentiality of metacaspases in P. vivax biology.
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Affiliation(s)
- Carolina Moreira Blanco
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil
| | - Hugo Amorim Dos Santos de Souza
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil
| | - Priscilla da Costa Martins
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil
| | - Camila Fabbri
- Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brasil
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), Manaus, Brasil
| | | | | | - Stefanie Costa Pinto Lopes
- Instituto Leônidas e Maria Deane, Fiocruz Amazônia, Manaus, Brasil
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado (FMT-HVD), Manaus, Brasil
| | - Lilian Rose Pratt-Riccio
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil
| | - Cláudio Tadeu Daniel-Ribeiro
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil
| | - Paulo Renato Rivas Totino
- Laboratório de Pesquisa em Malária, Instituto Oswaldo Cruz, Fiocruz and Centro de Pesquisa, Diagnóstico e Treinamento em Malária (CPD-Mal), Secretaria de Vigilância em Saúde e Ambiente (SVSA), Ministério da Saúde, Rio de Janeiro, Brasil.
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2
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Kumari V, Prasad KM, Kalia I, Sindhu G, Dixit R, Rawat DS, Singh OP, Singh AP, Pandey KC. Dissecting The role of Plasmodium metacaspase-2 in malaria gametogenesis and sporogony. Emerg Microbes Infect 2022; 11:938-955. [PMID: 35264080 PMCID: PMC8973346 DOI: 10.1080/22221751.2022.2052357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The family of apicomplexan specific proteins contains caspases–like proteins called “metacaspases”. These enzymes are present in the malaria parasite but absent in human; therefore, these can be explored as potential drug targets. We deleted the MCA-2 gene from Plasmodium berghei genome using a gene knockout strategy to decipher its precise function. This study has identified that MCA-2 plays an important role in parasite transmission since it is critical for the formation of gametocytes and for maintaining an appropriate number of infectious sporozoites required for sporogony. It is noticeable that a significant reduction in gametocyte, oocysts, ookinete and sporozoites load along with a delay in hepatocytes invasion were observed in the MCA-2 knockout parasite. Furthermore, a study found the two MCA-2 inhibitory molecules known as C-532 and C-533, which remarkably inhibited the MCA-2 activity, abolished the in vitro parasite growth, and also impaired the transmission cycle of P. falciparum and P. berghei in An. stephensi. Our findings indicate that the deletion of MCA-2 hampers the Plasmodium development during erythrocytic and exo-erythrocytic stages, and its inhibition by C-532 and C-533 critically affects the malaria transmission biology.
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Affiliation(s)
- Vandana Kumari
- ICMR-National Institute of Malaria Research, New Delhi, India
| | | | | | | | - Rajnikant Dixit
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Diwan S Rawat
- Depatment of Chemistry, University of Delhi, New Delhi, India
| | - O P Singh
- ICMR-National Institute of Malaria Research, New Delhi, India
| | - Agam P Singh
- National Institute of Immunology, New Delhi, India
| | - Kailash C Pandey
- ICMR-National Institute of Malaria Research, New Delhi, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad Uttar Pradesh, UP, India
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3
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Mohapatra AD, Zuromski J, Kurtis J. Assessing PfGARP-Mediated Apoptosis of Blood-Stage Plasmodium falciparum Parasites. Methods Mol Biol 2022; 2470:659-672. [PMID: 35881381 DOI: 10.1007/978-1-0716-2189-9_49] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Apoptosis is conventionally regarded as an evolutionarily conserved and genetically controlled process of programmed cell death confined to metazoan organisms. However, recently, conserved features of apoptosis have also been demonstrated in unicellular eukaryotes (Holzmuller et al. Parasitology 132:S19-S32, 2006; Le Chat et al. Mol Biochem Parasitol 153:41-47, 2007; Madeo et al. Curr Opin Microbiol 7:655-660, 2004; Welburn et al. Parasitology 132:S7-S18, 2006; Jensen et al. Science 216:1230-1233, 1982) including malaria parasites (Al-Olayan et al. Int J Parasitol 32:1133-1143, 2002; Ch'ng et al. Cell Death Dis 1:e26, 2010; Meslin et al. J Infect Dis 195:1852-1859, 2007; Picot et al. Trans R Soc Trop Med Hyg 91:590-591, 1997; Raj et al. Nature 582:104-108, 2020). P. falciparum glutamic-acid-rich protein (PfGARP) is an antigen of 80 kDa that is uniquely expressed on the exofacial surface of red blood cells (RBCs) infected by early-to-late-trophozoite-stage P. falciparum parasites (Raj et al. Nature 582:104-108, 2020). We have recently demonstrated that antibodies against PfGARP bind to the PfGARP displayed on the surface of P. falciparum trophozoite-infected RBCs and trigger apoptosis in the intracellular parasites (Raj et al. Nature 582:104-108, 2020). This is the first demonstration of antibody-induced apoptosis in blood-stage malaria parasites and is characterized by several conserved features such as crisis form morphology, loss of mitochondrial membrane potential, loss of integrity of food vacuole, activation of caspase-like cysteine proteases, and fragmentation of chromosomal DNA. Here we describe the assays used to detect these features of apoptosis in the mature blood stage of malaria parasites.
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Affiliation(s)
- Alok Das Mohapatra
- Department of Pathology and Laboratory Medicine, Brown University Medical School, Providence, RI, USA
| | - Jenna Zuromski
- Department of Pathology and Laboratory Medicine, Brown University Medical School, Providence, RI, USA
| | - Jonathan Kurtis
- Department of Pathology and Laboratory Medicine, Brown University Medical School, Providence, RI, USA.
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4
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de Souza HADS, Escafa VF, Blanco CM, Baptista BDO, de Barros JP, Riccio EKP, Rodrigues ABM, Melo GCD, Lacerda MVGD, de Souza RM, Lima-Junior JDC, Guimarães ACR, da Mota FF, da Silva JHM, Daniel-Ribeiro CT, Pratt-Riccio LR, Totino PRR. Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain is conserved in field isolates from Brazilian Amazon. Mem Inst Oswaldo Cruz 2021; 116:e200584. [PMID: 34076074 PMCID: PMC8186469 DOI: 10.1590/0074-02760200584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 05/04/2021] [Indexed: 11/22/2022] Open
Abstract
In the present study, we investigated the genetic diversity of Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain in two municipalities of the main malaria hotspot in Brazil, i.e., the Juruá Valley, and observed complete sequence identity among all P. vivax field isolates and the Sal-1 reference strain. Analysis of PvMCA1 catalytic domain in different P. vivax genomic sequences publicly available also revealed a high degree of conservation worldwide, with very few amino acid substitutions that were not related to putative histidine and cysteine catalytic residues, whose involvement with the active site of protease was herein predicted by molecular modeling. The genetic conservation presented by PvMCA1 may contribute to its eligibility as a druggable target candidate in vivax malaria.
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Affiliation(s)
| | - Victor Fernandes Escafa
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Carolina Moreira Blanco
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Bárbara de Oliveira Baptista
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Jenifer Peixoto de Barros
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Evelyn Ketty Pratt Riccio
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Aline Beatriz Mello Rodrigues
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Genômica Funcional e Bioinformática, Rio de Janeiro, RJ, Brasil
| | - Gisely Cardoso de Melo
- Universidade do Estado do Amazonas, Manaus, AM, Brasil.,Fundação de Medicina Tropical Heitor Vieira Dourado, Instituto de Pesquisa Clínica Carlos Borborema, Manaus, AM, Brasil
| | - Marcus Vinícius Guimarães de Lacerda
- Fundação de Medicina Tropical Heitor Vieira Dourado, Instituto de Pesquisa Clínica Carlos Borborema, Manaus, AM, Brasil.,Fundação Oswaldo Cruz-Fiocruz, Instituto Leônidas and Maria Deane, Manaus, AM, Brasil
| | - Rodrigo Medeiros de Souza
- Universidade Federal do Acre, Centro de Pesquisa em Doenças Infecciosas, Centro Multidisciplinar, Rio Branco, AC, Brasil
| | - Josué da Costa Lima-Junior
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Imunoparasitologia, Rio de Janeiro, RJ, Brasil
| | - Ana Carolina Ramos Guimarães
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Genômica Funcional e Bioinformática, Rio de Janeiro, RJ, Brasil
| | - Fabio Faria da Mota
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Computacional e Sistemas, Rio de Janeiro, RJ, Brasil
| | | | - Cláudio Tadeu Daniel-Ribeiro
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Lilian Rose Pratt-Riccio
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
| | - Paulo Renato Rivas Totino
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Pesquisa em Malária, Rio de Janeiro, RJ, Brasil
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5
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Kumar B, Verma S, Kashif M, Sharma R, Atul, Dixit R, Singh AP, Pande V, Saxena AK, Abid M, Pandey KC. Metacaspase-3 of Plasmodium falciparum: An atypical trypsin-like serine protease. Int J Biol Macromol 2019; 138:309-320. [PMID: 31301397 DOI: 10.1016/j.ijbiomac.2019.07.067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 07/03/2019] [Accepted: 07/09/2019] [Indexed: 02/05/2023]
Abstract
Metacaspases are clan CD cysteine peptidases found in plants, fungi and protozoa that possess a conserved Peptidase_C14 domain, homologous to the human caspases and a catalytic His/Cys dyad. Earlier reports have indicated the role of metacaspases in cell death; however, metacaspases of human malaria parasite remains poorly understood. In this study, we aimed to functionally characterize a novel malarial protease, P. falciparum metacaspase-3 (PfMCA3). Unlike other clan CD peptidases, PfMCA3 has an atypical active site serine (Ser1865) residue in place of canonical cysteine and it phylogenetically forms a distinct branch across the species. To investigate whether this domain retains catalytic activity, we expressed, purified and refolded the Peptidase_C14 domain of PfMCA3 which was found to express in all asexual stages. PfMCA3 exhibited trypsin-like serine protease activity with ser1865 acting as catalytic residue to cleave trypsin oligopeptide substrate. PfMCA3 is inhibited by trypsin-like serine protease inhibitors. Our study found that PfMCA3 enzymatic activity was abrogated when catalytic serine1865 (S1865A) was mutated. Moreover, PfMCA3 was found to be inactive against caspase substrate. Overall, our study characterizes a novel metacaspase of P. falciparum, different from human caspases and not responsible for the caspase-like activity, therefore, could be considered as a potential chemotherapeutic target.
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Affiliation(s)
- Bhumika Kumar
- National Institute of Malaria Research, New Delhi, 110077, India; Department of Bioscience, Jamia Millia Islamia, New Delhi 110025, India
| | - Sonia Verma
- National Institute of Malaria Research, New Delhi, 110077, India
| | | | - Ruby Sharma
- Jawaharlal Nehru University, New Delhi 110067, India
| | - Atul
- Kumaun University, Nainital, Uttarakhand, 263001, India
| | - Rajnikant Dixit
- National Institute of Malaria Research, New Delhi, 110077, India
| | - Agam P Singh
- National Institute of Immunology, New Delhi, 110067, India
| | - Veena Pande
- Kumaun University, Nainital, Uttarakhand, 263001, India
| | - Ajay K Saxena
- Jawaharlal Nehru University, New Delhi 110067, India
| | - Mohammad Abid
- Department of Bioscience, Jamia Millia Islamia, New Delhi 110025, India
| | - Kailash C Pandey
- National Institute of Malaria Research, New Delhi, 110077, India; National Institute for Research in Environmental Health, Bhopal, 462001, India.
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6
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Deu E. Proteases as antimalarial targets: strategies for genetic, chemical, and therapeutic validation. FEBS J 2017; 284:2604-2628. [PMID: 28599096 PMCID: PMC5575534 DOI: 10.1111/febs.14130] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 04/29/2017] [Accepted: 06/06/2017] [Indexed: 01/17/2023]
Abstract
Malaria is a devastating parasitic disease affecting half of the world's population. The rapid emergence of resistance against new antimalarial drugs, including artemisinin-based therapies, has made the development of drugs with novel mechanisms of action extremely urgent. Proteases are enzymes proven to be well suited for target-based drug development due to our knowledge of their enzymatic mechanisms and active site structures. More importantly, Plasmodium proteases have been shown to be involved in a variety of pathways that are essential for parasite survival. However, pharmacological rather than target-based approaches have dominated the field of antimalarial drug development, in part due to the challenge of robustly validating Plasmodium targets at the genetic level. Fortunately, over the last few years there has been significant progress in the development of efficient genetic methods to modify the parasite, including several conditional approaches. This progress is finally allowing us not only to validate essential genes genetically, but also to study their molecular functions. In this review, I present our current understanding of the biological role proteases play in the malaria parasite life cycle. I also discuss how the recent advances in Plasmodium genetics, the improvement of protease-oriented chemical biology approaches, and the development of malaria-focused pharmacological assays, can be combined to achieve a robust biological, chemical and therapeutic validation of Plasmodium proteases as viable drug targets.
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Affiliation(s)
- Edgar Deu
- Chemical Biology Approaches to Malaria LaboratoryThe Francis Crick InstituteLondonUK
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7
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Sow F, Bonnot G, Ahmed BR, Diagana SM, Kebe H, Koita M, Samba BM, Al-Mukhaini SK, Al-Zadjali M, Al-Abri SS, Ali OAM, Samy AM, Hamid MMA, Ali Albsheer MM, Simon B, Bienvenu AL, Petersen E, Picot S. Genetic diversity of Plasmodium vivax metacaspase 1 and Plasmodium vivax multi-drug resistance 1 genes of field isolates from Mauritania, Sudan and Oman. Malar J 2017; 16:61. [PMID: 28153009 PMCID: PMC5288979 DOI: 10.1186/s12936-017-1687-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 01/10/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Plasmodium vivax is the second most important human malaria parasite, widely spread across the world. This parasite is associated with important issues in the process toward malaria elimination, including potential for relapse and increased resistance to chloroquine. Plasmodium vivax multi-drug resistant (pvmdr1) is suspected to be a marker of resistance although definitive evidence is lacking. Progress has been made in knowledge of biological factors affecting parasite growth, including mechanisms of regulated cell death and the suspected role of metacaspase. Plasmodium vivax metacaspase1 (PvMCA1-cd) has been described with a catalytic domain composed of histidine (H372) and cysteine (C428) residues. The aim of this study was to test for a link between the conserved histidine and cysteine residues in PvMCA1-cd, and the polymorphism of the P. vivax multi-drug resistant gene (pvmdr1). RESULTS Thirty P. vivax isolates were collected from Mauritania, Sudan, and Oman. Among the 28 P. vivax isolates successfully sequenced, only 4 samples showed the conserved His (372)-Cys (428) residues in PvMCA1-cd. Single nucleotide polymorphisms observed were H372T (46.4%), H372D (39.3%), and C428R (85.7%). A new polymorphic catalytic domain was observed at His (282)-Cys (305) residues. Sequences alignment analysis of pvmdr1 showed SNP in the three codons 958, 976 and 1076. A single SNP was identified at the codon M958Y (60%), 2 SNPs were found at the position 976: Y976F (13%) and Y976V (57%), and 3 SNPs were identified at the position 1076: F1076L (40%), F1076T (53%) and F1076I (3%). Only one isolate was wildtype in all three codons (MYF), 27% were single MYL mutants, and 10% were double MFL mutants. Three new haplotypes were also identified: the triple mutant YVT was most prevalent (53.3%) distributed in the three countries, while triple YFL and YVI mutants (3%), were only found in samples from Sudan and Mauritania. CONCLUSIONS Triple or quadruple mutants for metacaspase genes and double or triple mutants for Pvmdr1 were observed in 24/28 and 19/28 samples. There was no difference in the frequency of mutations between PvMCA1-cd and Pvmdr1 (P > 0.2). Histidine and cysteine residues in PvMCA1-cd are highly polymorphic and linkage disequilibrium with SNPs of Pvmdr1 gene may be expected from these three areas with different patterns of P. vivax transmission.
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Affiliation(s)
- Fatimata Sow
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires ICBMS-UMR5246, CNRS-INSA-CPE, Malaria Research Unit, University Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, Lyon, 69622, Villeurbane, France.
| | - Guillaume Bonnot
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires ICBMS-UMR5246, CNRS-INSA-CPE, Malaria Research Unit, University Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, Lyon, 69622, Villeurbane, France
| | - Bilal Rabah Ahmed
- Laboratoire de Bactériologie et Parasitologie de l'Hôpital Cheikh Zayed, BP-5720, Nouakchott, Mauritania
| | - Sidi Mohamed Diagana
- Laboratoire de Bactériologie et Parasitologie de l'Hôpital Cheikh Zayed, BP-5720, Nouakchott, Mauritania
| | - Hachim Kebe
- Service des Maladies Infectieuses et Tropicales, Centre Hospitalier National de Nouakchott, BP-612, Nouakchott, Mauritania
| | - Mohamedou Koita
- Laboratoire de Parasitologie et de Mycologie Médicale Institut National de Recherches en Santé Publique (INRSP), Avenue Jemal AbdeNasser, BP-695, Nouakchott, Mauritania
| | - Ba Malado Samba
- Laboratoire Analyse de Biologie Médicale du Centre hospitalier de Rosso Mauritanie, BP-41, Rosso, Mauritania
| | - Said K Al-Mukhaini
- Department of Infectious Diseases, The Royal Hospital, Muscat, Oman.,Department of malaria, Ministry of Health, Muscat, Oman
| | - Majed Al-Zadjali
- Department of Infectious Diseases, The Royal Hospital, Muscat, Oman.,Department of malaria, Ministry of Health, Muscat, Oman
| | - Seif S Al-Abri
- Department of Infectious Diseases, The Royal Hospital, Muscat, Oman.,Department of malaria, Ministry of Health, Muscat, Oman
| | - Osama A M Ali
- Department of Infectious Diseases, The Royal Hospital, Muscat, Oman.,Department of malaria, Ministry of Health, Muscat, Oman
| | - Abdallah M Samy
- Entomology Department, Faculty of Science, Ain Shams University, Abbassia, Cairo, 11566, Egypt.,Biodiversity Institute, University of Kansas, Lawrence, KS, 66045, USA
| | - Muzamil Mahdi Abdel Hamid
- Department of Parasitology and Medical Entomology, Institute of Endemic Diseases, Medical Campus, University of Khartoum, Qassr Street, P.O. BOX 102, Khartoum, Sudan
| | - Musab M Ali Albsheer
- Department of Parasitology and Medical Entomology, Institute of Endemic Diseases, Medical Campus, University of Khartoum, Qassr Street, P.O. BOX 102, Khartoum, Sudan
| | - Bruno Simon
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires ICBMS-UMR5246, CNRS-INSA-CPE, Malaria Research Unit, University Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, Lyon, 69622, Villeurbane, France.,Institut of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
| | - Anne-Lise Bienvenu
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires ICBMS-UMR5246, CNRS-INSA-CPE, Malaria Research Unit, University Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, Lyon, 69622, Villeurbane, France.,Institut of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
| | - Eskild Petersen
- Department of Infectious Diseases, The Royal Hospital, Muscat, Oman.,Department of malaria, Ministry of Health, Muscat, Oman.,Institute of Clinical Medicine, Faculty of Health Science, University of Aarhus, Aarhus, Denmark
| | - Stéphane Picot
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires ICBMS-UMR5246, CNRS-INSA-CPE, Malaria Research Unit, University Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, Lyon, 69622, Villeurbane, France.,Institut of Parasitology and Medical Mycology, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
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8
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Plasmodium falciparum exhibits markers of regulated cell death at high population density in vitro. Parasitol Int 2016; 65:715-727. [DOI: 10.1016/j.parint.2016.07.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 11/22/2022]
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9
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Tuteja R. Emerging functions of helicases in regulation of stress survival in malaria parasite Plasmodium falciparum and their comparison with human host. Parasitol Int 2016; 65:645-664. [PMID: 27586396 DOI: 10.1016/j.parint.2016.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 06/28/2016] [Accepted: 08/28/2016] [Indexed: 02/04/2023]
Abstract
The cellular response to various stresses is a universal phenomenon and involves a common set of stress responses that are largely independent of the type of stress. The response to stress is complex and cells can activate multiple signaling pathways that act in concert to influence cell fate and results in a specific cellular outcome, including reduction in macromolecular synthesis by shared pathways, cell cycle arrest, DNA repair, senescence and/or apoptosis. Whether cells mount a protective response or die depends to a great degree on the nature and duration of the stress and the particular cell type. Helicases play essential roles in DNA replication, repair, recombination, transcription and translation, and also participate in RNA metabolic processes including pre-mRNA processing, ribosome biogenesis, RNA turnover, export, translation, surveillance, storage and decay. In order to survive in the human host, the malaria parasite Plasmodium falciparum has to handle variety of stresses, which it encounters during the erythrocytic stages of its life cycle. In recent past the role of helicases in imparting various stress responses has emerged. Therefore in the present review an attempt has been made to highlight the emerging importance of helicases in stress responses in malaria parasite and their comparison with human host is also presented. It is noteworthy that PfDHX33 and PfDDX60 are larger in size and different in sequence as compared to the HsDHX33 and HsDDX60. The study suggests that helicases are multifunctional and play major role in helping the cells to combat various stresses.
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Affiliation(s)
- Renu Tuteja
- Parasite Biology Group, International Centre for Genetic Engineering and Biotechnology, P. O. Box 10504, Aruna Asaf Ali Marg, New Delhi 110067, India.
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10
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Abstract
Mechanisms of cell death in unicellular parasites have been subjects of debate for the last decade, with studies demonstrating evidence of apoptosis or non-apoptosis like mechanisms, including necrosis, and autophagy. Recent clarifications on the definition of regulated or accidental cell death by The Nomenclature Committee on Cell Death provides an opportunity to reanalyze some data, re-evaluate conclusions in the light of parasite diversity, and to propose alternative arguments in the context of malaria drug resistance, considering lack of really new drugs in the pipeline. Deciphering the mechanisms of death may help in detection of new drug targets and the design of innovative drugs. However, classifications have been evolving rapidly since initial description of "programmed cell death", leading to some uncertainty as to whether Plasmodium cell death is accidental or regulated.
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Affiliation(s)
- Fatimata Sow
- University Claude Bernard Lyon 1, Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-UCBL1, 8 avenue Rockefeller, 69373 Lyon cedex 08, France
| | - Mary Nyonda
- University Claude Bernard Lyon 1, Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-UCBL1, 8 avenue Rockefeller, 69373 Lyon cedex 08, France
| | - Anne-Lise Bienvenu
- University Claude Bernard Lyon 1, Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-UCBL1, 8 avenue Rockefeller, 69373 Lyon cedex 08, France. ; Hospices Civils de Lyon, Institut de Parasitologie et de Mycologie Médicale (IP2M), Hôpital de la Croix-Rousse, 103 grande rue de la Croix-Rousse, 69317 Lyon cedex 04, France
| | - Stephane Picot
- University Claude Bernard Lyon 1, Malaria Research Unit, SMITh, ICBMS, UMR 5246 CNRS-INSA-CPE-UCBL1, 8 avenue Rockefeller, 69373 Lyon cedex 08, France. ; Hospices Civils de Lyon, Institut de Parasitologie et de Mycologie Médicale (IP2M), Hôpital de la Croix-Rousse, 103 grande rue de la Croix-Rousse, 69317 Lyon cedex 04, France
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Disruption of cellular homeostasis induces organelle stress and triggers apoptosis like cell-death pathways in malaria parasite. Cell Death Dis 2015; 6:e1803. [PMID: 26136076 PMCID: PMC4650714 DOI: 10.1038/cddis.2015.142] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 04/06/2015] [Accepted: 04/07/2015] [Indexed: 01/29/2023]
Abstract
A regulated protein turnover machinery in the cell is essential for effective cellular homeostasis; any interference with this system induces cellular stress and alters the normal functioning of proteins important for cell survival. In this study, we show that persistent cellular stress and organelle dysfunction because of disruption of cellular homeostasis in human malaria parasite Plasmodium falciparum, leads to apoptosis-like cell death. Quantitative global proteomic analysis of the stressed parasites before onset of cell death, showed upregulation of a number of proteins involved in cellular homeostasis; protein network analyses identified upregulated metabolic pathways that may be associated with stress tolerance and pro-survival mechanism. However, persistent stress on parasites cause structural abnormalities in endoplasmic reticulum and mitochondria, subsequently a cascade of reactions are initiated in parasites including rise in cytosolic calcium levels, loss of mitochondrial membrane potential and activation of VAD-FMK-binding proteases. We further show that activation of VAD-FMK-binding proteases in the parasites leads to degradation of phylogenetically conserved protein, TSN (Tudor staphylococcal nuclease), a known target of metacaspases, as well as degradation of other components of spliceosomal complex. Loss of spliceosomal machinery impairs the mRNA splicing, leading to accumulation of unprocessed RNAs in the parasite and thus dysregulate vital cellular functions, which in turn leads to execution of apoptosis-like cell death. Our results establish one of the possible mechanisms of instigation of cell death by organelle stress in Plasmodium.
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12
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Caspase-like proteins: Acanthamoeba castellanii metacaspase and Dictyostelium discoideum paracaspase, what are their functions? J Biosci 2014; 39:909-16. [DOI: 10.1007/s12038-014-9486-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Endoplasmic reticulum stress responses in Leishmania. Mol Biochem Parasitol 2014; 197:1-8. [PMID: 25224909 DOI: 10.1016/j.molbiopara.2014.09.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 08/14/2014] [Accepted: 09/05/2014] [Indexed: 11/23/2022]
Abstract
Perturbation of endoplasmic reticulum (ER) homeostasis can lead to an accumulation of misfolded proteins within the ER lumen causing initiation of ER stress. To reestablish homeostasis and mitigate the stress, a series of adaptive intracellular signaling pathways termed the unfolded protein response (UPR) are activated. ER stress is of considerable interest to parasitologists because it takes place in parasites subjected to adverse environmental conditions. During a digenetic lifestyle, Leishmania parasites encounter and adapt to harsh environmental conditions that provide potential triggers of ER stress. These include nutrient deficiency, hypoxia, oxidative stress, changing pH, and shifts in temperature. Protozoan human pathogens, including the causative agents of trypanosomiasis, leishmaniasis, toxoplasmosis and malaria, contain a minimal conventional UPR network relative to higher eukaryotic cells. Three different signaling pathways in the ER stress response have been described in trypanosomatids: these pathways involve (i) the down-regulation of translation by a protein kinase RNA-like ER kinase (PERK), (ii) the ER-associated degradation (ERAD) pathway, and (iii) the spliced leader silencing (SLS) pathway and its target mRNAs. Under short-term ER stress, signaling from PERK activates autophagy, a cell survival response. But both chronic and unresolved ER stresses lead to initiation of apoptotic events and eventual cell death. This review presents the current understanding of the ER stress response in Leishmania with an emphasis on protein folding and ER quality control, unfolded protein response, autophagy as well as apoptosis in reference to the mammalian system.
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14
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Sharma N, Mohanakrishnan D, Sharma UK, Kumar R, Richa, Sinha AK, Sahal D. Design, economical synthesis and antiplasmodial evaluation of vanillin derived allylated chalcones and their marked synergism with artemisinin against chloroquine resistant strains of Plasmodium falciparum. Eur J Med Chem 2014; 79:350-68. [DOI: 10.1016/j.ejmech.2014.03.079] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 03/24/2014] [Accepted: 03/27/2014] [Indexed: 10/25/2022]
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15
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Cheema HS, Prakash O, Pal A, Khan F, Bawankule DU, Darokar MP. Glabridin induces oxidative stress mediated apoptosis like cell death of malaria parasite Plasmodium falciparum. Parasitol Int 2014; 63:349-58. [DOI: 10.1016/j.parint.2013.12.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/12/2013] [Accepted: 12/10/2013] [Indexed: 01/14/2023]
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16
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Murik O, Elboher A, Kaplan A. Dehydroascorbate: a possible surveillance molecule of oxidative stress and programmed cell death in the green alga Chlamydomonas reinhardtii. THE NEW PHYTOLOGIST 2014; 202:471-484. [PMID: 24345283 DOI: 10.1111/nph.12649] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 11/18/2013] [Indexed: 05/06/2023]
Abstract
Chlamydomonas reinhardtii tolerates relatively high H2 O2 levels that induce an array of antioxidant activities. However, rather than rendering the cells more resistant to oxidative stress, the cells become far more sensitive to an additional H2 O2 dose. If H2 O2 is provided 1.5-9 h after an initial dose, it induces programmed cell death (PCD) in the wild-type, but not in the dum1 mutant impaired in the mitochondrial respiratory complex III. This mutant does not exhibit a secondary oxidative burst 4-5 h after the inducing H2 O2 , nor does it activate metacaspase-1 after the second H2 O2 treatment. The intracellular dehydroascorbate level, a product of ascorbate peroxidase, increases under conditions leading to PCD. The addition of dehydroascorbate induces PCD in the wild-type and dum1 cultures, but higher levels are required in dum1 cells, where it is metabolized faster. The application of dehydroascorbate induces the expression of metacaspase-2, which is much stronger than the expression of metacaspase-1. The presence or absence of oxidative stress, in addition to the rise in internal dehydroascorbate, may determine which metacaspase is activated during Chlamydomonas PCD. Cell death is strongly affected by the timing of H2 O2 or dehydroascorbate admission to synchronously grown cultures, suggesting that the cell cycle phase may distinguish cells that perish from those that do not.
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Affiliation(s)
- Omer Murik
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Ahinoam Elboher
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
| | - Aaron Kaplan
- Department of Plant and Environmental Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, 91904, Israel
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17
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Wang SH, You ZY, Ye LP, Che J, Qian Q, Nanjo Y, Komatsu S, Zhong BX. Quantitative Proteomic and Transcriptomic Analyses of Molecular Mechanisms Associated with Low Silk Production in Silkworm Bombyx mori. J Proteome Res 2014; 13:735-51. [DOI: 10.1021/pr4008333] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Shao-hua Wang
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
| | - Zheng-ying You
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
| | - Lu-peng Ye
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
| | - Jiaqian Che
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
| | - Qiujie Qian
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
| | - Yohei Nanjo
- National
Institute of Crop Science, NARO, Kannondai 2-1-18, Tsukuba 305-8518, Japan
| | - Setsuko Komatsu
- National
Institute of Crop Science, NARO, Kannondai 2-1-18, Tsukuba 305-8518, Japan
| | - Bo-xiong Zhong
- College
of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P.R. China
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18
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Tremp AZ, Carter V, Saeed S, Dessens JT. Morphogenesis of Plasmodium zoites is uncoupled from tensile strength. Mol Microbiol 2013; 89:552-64. [PMID: 23773015 PMCID: PMC3912903 DOI: 10.1111/mmi.12297] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2013] [Indexed: 12/17/2022]
Abstract
A shared feature of the motile stages (zoites) of malaria parasites is a cortical cytoskeletal structure termed subpellicular network (SPN), thought to define and maintain cell shape. Plasmodium alveolins comprise structural components of the SPN, and alveolin gene knockout causes morphological abnormalities that coincide with markedly reduced tensile strength of the affected zoites, indicating the alveolins are prime cell shape determinants. Here, we characterize a novel SPN protein of Plasmodium berghei ookinetes and sporozoites named G2 (glycine at position 2), which is structurally unrelated to alveolins. G2 knockout abolishes parasite transmission and causes zoite malformations and motility defects similar to those observed in alveolin null mutants. Unlike alveolins, however, G2 contributes little to tensile strength, arguing against a cause-effect relationship between tensile strength and cell shape. We also show that G2 null mutant sporozoites display an abnormal arrangement of their subpellicular microtubules. These results provide important new understanding of the factors that determine zoite morphogenesis, as well as the potential roles of the cortical cytoskeleton in gliding motility.
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Affiliation(s)
- Annie Z Tremp
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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19
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Pollitt LC, Churcher TS, Dawes EJ, Khan SM, Sajid M, Basáñez MG, Colegrave N, Reece SE. Costs of crowding for the transmission of malaria parasites. Evol Appl 2013; 6:617-29. [PMID: 23789029 PMCID: PMC3684743 DOI: 10.1111/eva.12048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 12/13/2012] [Accepted: 12/13/2012] [Indexed: 01/03/2023] Open
Abstract
The utility of using evolutionary and ecological frameworks to understand the dynamics of infectious diseases is gaining increasing recognition. However, integrating evolutionary ecology and infectious disease epidemiology is challenging because within-host dynamics can have counterintuitive consequences for between-host transmission, especially for vector-borne parasites. A major obstacle to linking within- and between-host processes is that the drivers of the relationships between the density, virulence, and fitness of parasites are poorly understood. By experimentally manipulating the intensity of rodent malaria (Plasmodium berghei) infections in Anopheles stephensi mosquitoes under different environmental conditions, we show that parasites experience substantial density-dependent fitness costs because crowding reduces both parasite proliferation and vector survival. We then use our data to predict how interactions between parasite density and vector environmental conditions shape within-vector processes and onward disease transmission. Our model predicts that density-dependent processes can have substantial and unexpected effects on the transmission potential of vector-borne disease, which should be considered in the development and evaluation of transmission-blocking interventions.
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Affiliation(s)
- Laura C Pollitt
- Institute of Evolutionary Biology, University of Edinburgh Edinburgh, UK ; Center for Infectious Disease Dynamics, Pennsylvania State University University Park, PA, USA
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21
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Abstract
Ultraviolet (UV) radiation can cause stresses or act as a photoregulatory signal depending on its wavelengths and fluence rates. Although the most harmful effects of UV on living cells are generally attributed to UV-B radiation, UV-A radiation can also affect many aspects of cellular processes. In cyanobacteria, most studies have concentrated on the damaging effect of UV and defense mechanisms to withstand UV stress. However, little is known about the activation mechanism of signaling components or their pathways which are implicated in the process following UV irradiation. Motile cyanobacteria use a very precise negative phototaxis signaling system to move away from high levels of solar radiation, which is an effective escape mechanism to avoid the detrimental effects of UV radiation. Recently, two different UV-A-induced signaling systems for regulating cyanobacterial phototaxis were characterized at the photophysiological and molecular levels. Here, we review the current understanding of the UV-A mediated signaling pathways in the context of the UV-A perception mechanism, early signaling components, and negative phototactic responses. In addition, increasing evidences supporting a role of pterins in response to UV radiation are discussed. We outline the effect of UV-induced cell damage, associated signaling molecules, and programmed cell death under UV-mediated oxidative stress.
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22
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Cai H, Kuang R, Gu J, Wang Y. Proteases in malaria parasites - a phylogenomic perspective. Curr Genomics 2012; 12:417-27. [PMID: 22379395 PMCID: PMC3178910 DOI: 10.2174/138920211797248565] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 07/17/2011] [Accepted: 07/20/2011] [Indexed: 12/21/2022] Open
Abstract
Malaria continues to be one of the most devastating global health problems due to the high morbidity and mortality it causes in endemic regions. The search for new antimalarial targets is of high priority because of the increasing prevalence of drug resistance in malaria parasites. Malarial proteases constitute a class of promising therapeutic targets as they play important roles in the parasite life cycle and it is possible to design and screen for specific protease inhibitors. In this mini-review, we provide a phylogenomic overview of malarial proteases. An evolutionary perspective on the origin and divergence of these proteases will provide insights into the adaptive mechanisms of parasite growth, development, infection, and pathogenesis.B
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Affiliation(s)
- Hong Cai
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
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23
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Sinai AP, Roepe PD. Autophagy in Apicomplexa: a life sustaining death mechanism? Trends Parasitol 2012; 28:358-64. [PMID: 22819059 DOI: 10.1016/j.pt.2012.06.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 06/25/2012] [Accepted: 06/26/2012] [Indexed: 12/15/2022]
Abstract
Programmed cell death (PCD) pathways remain understudied in parasitic protozoa in spite of the fact that they provide potential targets for the development of new therapy. The best understood PCD pathway in higher eukaryotes is apoptosis although emerging evidence also points to autophagy as a mediator of death in certain physiological contexts. Bioinformatic analyses coupled with biochemical and cell biological studies suggest that parasitic protozoa possess the capacity for PCD including a primordial form of apoptosis. Recent work in Toxoplasma and emerging data from Plasmodium suggest that autophagy-related processes may serve as an additional death promoting pathway in Apicomplexa. Detailed mechanistic studies into the molecular basis for PCD in parasitic protozoa represent a fertile area for investigation and drug development.
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Affiliation(s)
- Anthony P Sinai
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40526, USA.
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24
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Ch'ng JH, Renia L, Nosten F, Tan KSW. Can we teach an old drug new tricks? Trends Parasitol 2012; 28:220-4. [PMID: 22445323 DOI: 10.1016/j.pt.2012.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/07/2012] [Accepted: 02/08/2012] [Indexed: 11/19/2022]
Abstract
Although resistance to chloroquine (CQ) has relegated it from modern chemotherapeutic strategies to treat Plasmodium falciparum malaria, new evidence suggests that higher doses of the drug may exert a different killing mechanism and offers this drug a new lease of life. Whereas the established antimalarial mechanisms of CQ are usually associated with nanomolar levels of the drug, micromolar levels of CQ trigger a distinct cell death pathway involving the permeabilization of the digestive vacuole of the parasite and a release of hydrolytic enzymes. In this paper, we propose that this pathway is a promising antimalarial strategy and suggest that revising the CQ treatment regimen may elevate blood drug levels to trigger this pathway without increasing the incidence of adverse reactions.
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Affiliation(s)
- Jun-Hong Ch'ng
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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25
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On Programmed Cell Death in Plasmodium falciparum: Status Quo. J Trop Med 2012; 2012:646534. [PMID: 22287973 PMCID: PMC3263642 DOI: 10.1155/2012/646534] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Accepted: 09/16/2011] [Indexed: 11/25/2022] Open
Abstract
Conflicting arguments and results exist regarding the occurrence and phenotype of programmed cell death (PCD) in the malaria parasite Plasmodium falciparum. Inconsistencies relate mainly to the number and type of PCD markers assessed and the different methodologies used in the studies. In this paper, we provide a comprehensive overview of the current state of knowledge and empirical evidence for PCD in the intraerythrocytic stages of P. falciparum. We consider possible reasons for discrepancies in the data and offer suggestions towards more standardised investigation methods in this field. Furthermore, we present genomic evidence for PCD machinery in P. falciparum. We discuss the potential adaptive or nonadaptive role of PCD in the parasite life cycle and its possible exploitation in the development of novel drug targets. Lastly, we pose pertinent unanswered questions concerning the PCD phenomenon in P. falciparum to provide future direction.
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26
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Lilburn TG, Cai H, Zhou Z, Wang Y. Protease-associated cellular networks in malaria parasite Plasmodium falciparum. BMC Genomics 2011; 12 Suppl 5:S9. [PMID: 22369208 PMCID: PMC3287505 DOI: 10.1186/1471-2164-12-s5-s9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Malaria continues to be one of the most severe global infectious diseases, responsible for 1-2 million deaths yearly. The rapid evolution and spread of drug resistance in parasites has led to an urgent need for the development of novel antimalarial targets. Proteases are a group of enzymes that play essential roles in parasite growth and invasion. The possibility of designing specific inhibitors for proteases makes them promising drug targets. Previously, combining a comparative genomics approach and a machine learning approach, we identified the complement of proteases (degradome) in the malaria parasite Plasmodium falciparum and its sibling species [1-3], providing a catalog of targets for functional characterization and rational inhibitor design. Network analysis represents another route to revealing the role of proteins in the biology of parasites and we use this approach here to expand our understanding of the systems involving the proteases of P. falciparum. Results We investigated the roles of proteases in the parasite life cycle by constructing a network using protein-protein association data from the STRING database [4], and analyzing these data, in conjunction with the data from protein-protein interaction assays using the yeast 2-hybrid (Y2H) system [5], blood stage microarray experiments [6-8], proteomics [9-12], literature text mining, and sequence homology analysis. Seventy-seven (77) out of 124 predicted proteases were associated with at least one other protein, constituting 2,431 protein-protein interactions (PPIs). These proteases appear to play diverse roles in metabolism, cell cycle regulation, invasion and infection. Their degrees of connectivity (i.e., connections to other proteins), range from one to 143. The largest protease-associated sub-network is the ubiquitin-proteasome system which is crucial for protein recycling and stress response. Proteases are also implicated in heat shock response, signal peptide processing, cell cycle progression, transcriptional regulation, and signal transduction networks. Conclusions Our network analysis of proteases from P. falciparum uses a so-called guilt-by-association approach to extract sets of proteins from the proteome that are candidates for further study. Novel protease targets and previously unrecognized members of the protease-associated sub-systems provide new insights into the mechanisms underlying parasitism, pathogenesis and virulence.
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Affiliation(s)
- Timothy G Lilburn
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
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27
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Reece SE, Pollitt LC, Colegrave N, Gardner A. The meaning of death: evolution and ecology of apoptosis in protozoan parasites. PLoS Pathog 2011; 7:e1002320. [PMID: 22174671 PMCID: PMC3234211 DOI: 10.1371/journal.ppat.1002320] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The discovery that an apoptosis-like, programmed cell death (PCD) occurs in a broad range of protozoan parasites offers novel therapeutic tools to treat some of the most serious infectious diseases of humans, companion animals, wildlife, and livestock. Whilst apoptosis is an essential part of normal development, maintenance, and defence in multicellular organisms, its occurrence in unicellular parasites appears counter-intuitive and has proved highly controversial: according to the Darwinian notion of “survival of the fittest”, parasites are expected to evolve strategies to maximise their proliferation, not death. The prevailing, and untested, opinion in the literature is that parasites employ apoptosis to “altruistically” self-regulate the intensity of infection in the host/vector. However, evolutionary theory tells us that at most, this can only be part of the explanation, and other non-mutually exclusive hypotheses must also be tested. Here, we explain the evolutionary concepts that can explain apoptosis in unicellular parasites, highlight the key questions, and outline the approaches required to resolve the controversy over whether parasites “commit suicide”. We highlight the need for integration of proximate and functional approaches into an evolutionary framework to understand apoptosis in unicellular parasites. Understanding how, when, and why parasites employ apoptosis is central to targeting this process with interventions that are sustainable in the face of parasite evolution.
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Affiliation(s)
- Sarah E Reece
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.
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28
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Abstract
SUMMARYPlasmodium falciparum has for some time been developing resistance against known anti-malarial drugs, and therefore a new drug is urgently needed. Selenium (Se), an essential trace element, in the form of inorganic Se, selenite (SeO32−), has been reported to have an anti-plasmodial effect, but its mechanism is still unclear. In the present study, we evaluated the anti-plasmodial effect of several Se compounds against P. falciparum in vitro. The anti-plasmodial effect of several Se compounds was analysed and their apoptosis-inducing activity was evaluated by morphological observation, DNA fragmentation assay and mitochondrial function analysis. SeO32−, methylseleninic acid, selenomethionine and selenocystine have anti-plasmodial effects with 50% inhibition concentration at 9, 10, 45, and 65 μm, respectively, while selenate and methylselenocysteine up to 100 μm have no effect on parasite growth. The effective Se compounds caused the parasites to become shrunken and pyknotic and significantly increased mitochondrial damage against P. falciparum compared to the untreated control. In conclusion, SeO32−, methylseleninic acid, selenomethionine and selenocystine have anti-plasmodial activities that induce apoptosis-like cell death in P. falciparum, and the anti-plasmodial effects of Se seem to be based on its chemical forms. The apoptosis-like cell-death mechanism in P. falciparum can be beneficial to respond to the growing problem of drug resistance.
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A programmed cell death pathway in the malaria parasite Plasmodium falciparum has general features of mammalian apoptosis but is mediated by clan CA cysteine proteases. Cell Death Dis 2011; 1:e26. [PMID: 21364634 PMCID: PMC3032337 DOI: 10.1038/cddis.2010.2] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Several recent discoveries of the hallmark features of programmed cell death (PCD) in Plasmodium falciparum have presented the possibility of revealing novel targets for antimalarial therapy. Using a combination of cell-based assays, flow cytometry and fluorescence microscopy, we detected features including mitochondrial dysregulation, activation of cysteine proteases and in situ DNA fragmentation in parasites induced with chloroquine (CQ) and staurosporine (ST). The use of the pan-caspase inhibitor, z-Val-Ala-Asp-fmk (zVAD), and the mitochondria outer membrane permeabilization (MOMP) inhibitor, 4-hydroxy-tamoxifen, enabled the characterization of a novel CQ-induced pathway linking cysteine protease activation to downstream mitochondrial dysregulation, amplified protease activity and DNA fragmentation. The PCD features were observed only at high (μM) concentrations of CQ. The use of a new synthetic coumarin-labeled chloroquine (CM-CQ) showed that these features may be associated with concentration-dependent differences in drug localization. By further using cysteine protease inhibitors z-Asp-Glu-Val-Asp-fmk (zDEVD), z-Phe-Ala-fmk (zFA), z-Phe-Phe-fmk (zFF), z-Leu-Leu-Leu-fmk (zLLL), E64d and CA-074, we were able to implicate clan CA cysteine proteases in CQ-mediated PCD. Finally, CQ induction of two CQ-resistant parasite strains, 7G8 and K1, reveals the existence of PCD features in these parasites, the extent of which was less than 3D7. The use of the chemoreversal agent verapamil implicates the parasite digestive vacuole in mediating CQ-induced PCD.
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Meslin B, Beavogui AH, Fasel N, Picot S. Plasmodium falciparum metacaspase PfMCA-1 triggers a z-VAD-fmk inhibitable protease to promote cell death. PLoS One 2011; 6:e23867. [PMID: 21858231 PMCID: PMC3157471 DOI: 10.1371/journal.pone.0023867] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 07/27/2011] [Indexed: 12/11/2022] Open
Abstract
Activation of proteolytic cell death pathways may circumvent drug resistance in deadly protozoan parasites such as Plasmodium falciparum and Leishmania. To this end, it is important to define the cell death pathway(s) in parasites and thus characterize proteases such as metacaspases (MCA), which have been reported to induce cell death in plants and Leishmania parasites. We, therefore, investigated whether the cell death function of MCA is conserved in different protozoan parasite species such as Plasmodium falciparum and Leishmania major, focusing on the substrate specificity and functional role in cell survival as compared to Saccharomyces cerevisae. Our results show that, similarly to Leishmania, Plasmodium MCA exhibits a calcium-dependent, arginine-specific protease activity and its expression in yeast induced growth inhibition as well as an 82% increase in cell death under oxidative stress, a situation encountered by parasites during the host or when exposed to drugs such as artemisins. Furthermore, we show that MCA cell death pathways in both Plasmodium and Leishmania, involve a z-VAD-fmk inhibitable protease. Our data provide evidence that MCA from both Leishmania and Plasmodium falciparum is able to induce cell death in stress conditions, where it specifically activates a downstream enzyme as part of a cell death pathway. This enzymatic activity is also induced by the antimalarial drug chloroquine in erythrocytic stages of Plasmodium falciparum. Interestingly, we found that blocking parasite cell death influences their drug sensitivity, a result which could be used to create therapeutic strategies that by-pass drug resistance mechanisms by acting directly on the innate pathways of protozoan cell death.
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Affiliation(s)
- Benoît Meslin
- Malaria Research Unit, ICBMS UMR 5246 CNRS-UCBL1-INSA, Lyon, France
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31
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Rezanezhad H, Menegon M, Sarkari B, Hatam GR, Severini C. Characterization of the metacaspase 1 gene in Plasmodium vivax field isolates from southern Iran and Italian imported cases. Acta Trop 2011; 119:57-60. [PMID: 21524640 DOI: 10.1016/j.actatropica.2011.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 03/18/2011] [Accepted: 03/23/2011] [Indexed: 12/29/2022]
Abstract
Plasmodium vivax is still the more prevalent human Plasmodium outside Africa and despite this fact, there is still a deep lack of knowledge on its biology. Metacaspases are cysteine proteases related to metazoan caspases, involved in programmed cell death. Here, we have characterized the P. vivax metacaspase 1 gene in a total of 63 vivax isolates, 32 isolates collected in southern Iran and 31 Italian imported isolates originating from 12 different endemic countries. We have firstly identified DNA size polymorphism in P. vivax metacaspase 1 gene. A total of four different allelic sizes were found, resulting from the insertion of 1 to 4 tandem repeat units located within the intronic region of the P. vivax metacaspase 1. Similarly, we also have identified four distinct allelic types by using vivax merozoite surface protein-1 size polymorphism analysis.
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Affiliation(s)
- H Rezanezhad
- School of Pharmacy, University of Camerino, Camerino, Italy
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32
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Kaczanowski S, Sajid M, Reece SE. Evolution of apoptosis-like programmed cell death in unicellular protozoan parasites. Parasit Vectors 2011; 4:44. [PMID: 21439063 PMCID: PMC3077326 DOI: 10.1186/1756-3305-4-44] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 03/25/2011] [Indexed: 11/10/2022] Open
Abstract
Apoptosis-like programmed cell death (PCD) has recently been described in multiple taxa of unicellular protists, including the protozoan parasites Plasmodium, Trypanosoma and Leishmania. Apoptosis-like PCD in protozoan parasites shares a number of morphological features with programmed cell death in multicellular organisms. However, both the evolutionary explanations and mechanisms involved in parasite PCD are poorly understood. Explaining why unicellular organisms appear to undergo 'suicide' is a challenge for evolutionary biology and uncovering death executors and pathways is a challenge for molecular and cell biology. Bioinformatics has the potential to integrate these approaches by revealing homologies in the PCD machinery of diverse taxa and evaluating their evolutionary trajectories. As the molecular mechanisms of apoptosis in model organisms are well characterised, and recent data suggest similar mechanisms operate in protozoan parasites, key questions can now be addressed. These questions include: which elements of apoptosis machinery appear to be shared between protozoan parasites and multicellular taxa and, have these mechanisms arisen through convergent or divergent evolution? We use bioinformatics to address these questions and our analyses suggest that apoptosis mechanisms in protozoan parasites and other taxa have diverged during their evolution, that some apoptosis factors are shared across taxa whilst others have been replaced by proteins with similar biochemical activities.
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Affiliation(s)
- Szymon Kaczanowski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa Pawinskiego 5A 02-106, Poland.
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33
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Meslin B, Zalila H, Fasel N, Picot S, Bienvenu AL. Are protozoan metacaspases potential parasite killers? Parasit Vectors 2011; 4:26. [PMID: 21356053 PMCID: PMC3058108 DOI: 10.1186/1756-3305-4-26] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 02/28/2011] [Indexed: 11/10/2022] Open
Abstract
Mechanisms concerning life or death decisions in protozoan parasites are still imperfectly understood. Comparison with higher eukaryotes has led to the hypothesis that caspase-like enzymes could be involved in death pathways. This hypothesis was reinforced by the description of caspase-related sequences in the genome of several parasites, including Plasmodium, Trypanosoma and Leishmania. Although several teams are working to decipher the exact role of metacaspases in protozoan parasites, partial, conflicting or negative results have been obtained with respect to the relationship between protozoan metacaspases and cell death. The aim of this paper is to review current knowledge of protozoan parasite metacaspases within a drug targeting perspective.
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Affiliation(s)
- Benoît Meslin
- Malaria Research Unit, University Lyon 1, 8 Avenue Rockefeller, 69373 Lyon cedex 08, France
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34
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Rosenthal PJ. Falcipains and other cysteine proteases of malaria parasites. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 712:30-48. [PMID: 21660657 DOI: 10.1007/978-1-4419-8414-2_3] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A number of cysteine proteases of malaria parasites have been described and many more are suggested by analysis of the Plasmodium falciparum genome sequence. The best characterized of these proteases are the falcipains, a family of four papain-family enzymes. Falcipain-2 and falcipain-3 act in concert with other proteases to hydrolyze host erythrocyte hemoglobin in the parasite food vacuole. Disruption of the falcipain-2 gene led to a transient block in hemoglobin hydrolysis and parasites with increased sensitivity to protease inhibitors. Disruption of the falcipain-3 gene was not possible, strongly suggesting that this protease is essential for erythrocytic parasites. Disruption of the falcipain-1 gene did not alter development in erythrocytes, but led to decreased production of oocysts in mosquitoes. other papain-family proteases predicted by the genome sequence include dipeptidyl peptidases, a calpain homolog and serine-repeat antigens (SERAs). Dipeptidyl aminopeptidase 1 appears to be essential and localized to the food vacuole, suggesting a role in hemoglobin hydrolysis. Dipeptidyl aminopeptidase 3 appears to play a role in the rupture of erythrocytes by mature parasites. the P. falciparum calpain homolog gene could not be disrupted, suggesting that the protein is essential and a role in the parasite cell cycle has been suggested. Nine P. falciparum SERAs have cysteine protease motifs, but in some the active site cys is replaced by a Ser. Gene disruption studies suggested that SERA-5 and SERA-6 are essential. activation of SERA-5 by a serine protease seems to be required for merozoite egress from the erythrocyte. New drugs for malaria are greatly needed and cysteine proteases represent potential drug targets. cysteine protease inhibitors have demonstrated potent antimalarial effects and the optimization and testing of falcipain inhibitor antimalarials is underway.
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Affiliation(s)
- Philip J Rosenthal
- Department of Medicine, San Francisco General Hospital, University of California, San Francisco, California, USA.
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35
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Lüder CG, Campos-Salinas J, Gonzalez-Rey E, van Zandbergen G. Impact of protozoan cell death on parasite-host interactions and pathogenesis. Parasit Vectors 2010; 3:116. [PMID: 21126352 PMCID: PMC3003647 DOI: 10.1186/1756-3305-3-116] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 12/02/2010] [Indexed: 12/18/2022] Open
Abstract
PCD in protozoan parasites has emerged as a fascinating field of parasite biology. This not only relates to the underlying mechanisms and their evolutionary implications but also to the impact on the parasite-host interactions within mammalian hosts and arthropod vectors. During recent years, common functions of apoptosis and autophagy in protozoa and during parasitic infections have emerged. Here, we review how distinct cell death pathways in Trypanosoma, Leishmania, Plasmodium or Toxoplasma may contribute to regulation of parasite cell densities in vectors and mammalian hosts, to differentiation of parasites, to stress responses, and to modulation of the host immunity. The examples provided indicate crucial roles of PCD in parasite biology. The existence of PCD pathways in these organisms and the identification as being critical for parasite biology and parasite-host interactions could serve as a basis for developing new anti-parasitic drugs that take advantage of these pathways.
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Affiliation(s)
- Carsten Gk Lüder
- Institute for Medical Microbiology, Georg-August-University, Kreuzbergring 57, 37075 Göttingen, Germany.
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36
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Entamoeba histolytica: Differential gene expression during programmed cell death and identification of early pro- and anti-apoptotic signals. Exp Parasitol 2010; 126:497-505. [DOI: 10.1016/j.exppara.2010.05.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 05/26/2010] [Accepted: 05/27/2010] [Indexed: 11/21/2022]
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37
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Tremp AZ, Dessens JT. Malaria IMC1 membrane skeleton proteins operate autonomously and participate in motility independently of cell shape. J Biol Chem 2010; 286:5383-91. [PMID: 21098480 PMCID: PMC3037651 DOI: 10.1074/jbc.m110.187195] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Plasmodium IMC1 (inner membrane complex 1) proteins comprise components of the subpellicular network, a lattice of intermediate filaments that form a structural part of the pellicle in the zoite stages of malaria parasites. Family members IMC1a and IMC1b are differentially expressed in sporozoites and ookinetes, respectively, but have functionally equivalent roles affecting cell morphology, strength, motility, and infectivity. Because of the coincident effects of previous imc1 gene disruptions on both zoite shape and locomotion, it has been impossible to ascribe a direct involvement in motility to these proteins. We show here that a third family member, IMC1h, has a distinct differential expression pattern and localizes to the pellicle of both ookinetes and sporozoites. Knock-out of IMC1h mimics the loss-of-function phenotypes of IMC1a and IMC1b in their respective life stages, indicating that IMC1 proteins could be operating co-dependently. By generating double null mutant parasites for IMC1h and IMC1b, we tested this hypothesis: double knock-out exacerbated the phenotypes of the single knock-outs in terms of ookinete strength, motility, and infectivity but did not further affect ookinete morphology. These findings provide the first genetic evidence that IMC1 proteins can function independently of each other and contribute to gliding motility independently of cell shape.
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Affiliation(s)
- Annie Z Tremp
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
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38
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Pollitt LC, Colegrave N, Khan SM, Sajid M, Reece SE. Investigating the evolution of apoptosis in malaria parasites: the importance of ecology. Parasit Vectors 2010; 3:105. [PMID: 21080937 PMCID: PMC3136143 DOI: 10.1186/1756-3305-3-105] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Accepted: 11/16/2010] [Indexed: 11/16/2022] Open
Abstract
Apoptosis is a precisely regulated process of cell death which occurs widely in multicellular organisms and is essential for normal development and immune defences. In recent years, interest has grown in the occurrence of apoptosis in unicellular organisms. In particular, as apoptosis has been reported in a wide range of species, including protozoan malaria parasites and trypanosomes, it may provide a novel target for intervention. However, it is important to understand when and why parasites employ an apoptosis strategy before the likely long- and short-term success of such an intervention can be evaluated. The occurrence of apoptosis in unicellular parasites provides a challenge for evolutionary theory to explain as organisms are expected to have evolved to maximise their own proliferation, not death. One possible explanation is that protozoan parasites undergo apoptosis in order to gain a group benefit from controlling their density as this prevents premature vector mortality. However, experimental manipulations to examine the ultimate causes behind apoptosis in parasites are lacking. In this review, we focus on malaria parasites to outline how an evolutionary framework can help make predictions about the ecological circumstances under which apoptosis could evolve. We then highlight the ecological considerations that should be taken into account when designing evolutionary experiments involving markers of cell death, and we call for collaboration between researchers in different fields to identify and develop appropriate markers in reference to parasite ecology and to resolve debates on terminology.
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Affiliation(s)
- Laura C Pollitt
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, School of Biological Sciences, Edinburgh, EH9 3JT, UK
| | - Nick Colegrave
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, School of Biological Sciences, Edinburgh, EH9 3JT, UK
| | - Shahid M Khan
- Leiden Malaria Research group, Department of Parasitology, Leiden University Medical Center, The Netherlands
| | - Mohammed Sajid
- Leiden Malaria Research group, Department of Parasitology, Leiden University Medical Center, The Netherlands
| | - Sarah E Reece
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, School of Biological Sciences, Edinburgh, EH9 3JT, UK
- Centre for Immunity, Infection and Evolution, University of Edinburgh, School of Biological Sciences, Edinburgh, EH9 3JT, UK
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Jiménez-Ruiz A, Alzate JF, Macleod ET, Lüder CGK, Fasel N, Hurd H. Apoptotic markers in protozoan parasites. Parasit Vectors 2010; 3:104. [PMID: 21062457 PMCID: PMC2993696 DOI: 10.1186/1756-3305-3-104] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Accepted: 11/09/2010] [Indexed: 12/25/2022] Open
Abstract
The execution of the apoptotic death program in metazoans is characterized by a sequence of morphological and biochemical changes that include cell shrinkage, presentation of phosphatidylserine at the cell surface, mitochondrial alterations, chromatin condensation, nuclear fragmentation, membrane blebbing and the formation of apoptotic bodies. Methodologies for measuring apoptosis are based on these markers. Except for membrane blebbing and formation of apoptotic bodies, all other events have been observed in most protozoan parasites undergoing cell death. However, while techniques exist to detect these markers, they are often optimised for metazoan cells and therefore may not pick up subtle differences between the events occurring in unicellular organisms and multi-cellular organisms. In this review we discuss the markers most frequently used to analyze cell death in protozoan parasites, paying special attention to changes in cell morphology, mitochondrial activity, chromatin structure and plasma membrane structure/permeability. Regarding classical regulators/executors of apoptosis, we have reviewed the present knowledge of caspase-like and nuclease activities.
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Affiliation(s)
- Antonio Jiménez-Ruiz
- Departamento de Bioquímica y Biología Molecular, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
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40
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Ali M, Al-Olayan EM, Lewis S, Matthews H, Hurd H. Naturally occurring triggers that induce apoptosis-like programmed cell death in Plasmodium berghei ookinetes. PLoS One 2010; 5. [PMID: 20844583 PMCID: PMC2936559 DOI: 10.1371/journal.pone.0012634] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 08/10/2010] [Indexed: 01/01/2023] Open
Abstract
Several protozoan parasites have been shown to undergo a form of programmed cell death that exhibits morphological features associated with metazoan apoptosis. These include the rodent malaria parasite, Plasmodium berghei. Malaria zygotes develop in the mosquito midgut lumen, forming motile ookinetes. Up to 50% of these exhibit phenotypic markers of apoptosis; as do those grown in culture. We hypothesised that naturally occurring signals induce many ookinetes to undergo apoptosis before midgut traversal. To determine whether nitric oxide and reactive oxygen species act as such triggers, ookinetes were cultured with donors of these molecules. Exposure to the nitric oxide donor SNP induced a significant increase in ookinetes with condensed nuclear chromatin, activated caspase-like molecules and translocation of phosphatidylserine that was dose and time related. Results from an assay that detects the potential-dependent accumulation of aggregates of JC-1 in mitochondria suggested that nitric oxide does not operate via loss of mitochondrial membrane potential. L-DOPA (reactive oxygen species donor) also caused apoptosis in a dose and time dependent manner. Removal of white blood cells significantly decreased ookinetes exhibiting a marker of apoptosis in vitro. Inhibition of the activity of nitric oxide synthase in the mosquito midgut epithelium using L-NAME significantly decreased the proportion of apoptotic ookinetes and increased the number of oocysts that developed. Introduction of a nitric oxide donor into the blood meal had no effect on mosquito longevity but did reduce prevalence and intensity of infection. Thus, nitric oxide and reactive oxygen species are triggers of apoptosis in Plasmodium ookinetes. They occur naturally in the mosquito midgut lumen, sourced from infected blood and mosquito tissue. Up regulation of mosquito nitric oxide synthase activity has potential as a transmission blocking strategy.
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Affiliation(s)
- Medhat Ali
- School of Life Sciences, Keele University, Keele, United Kingdom
- Department of Zoology, Ain Shams University, Cairo, Egypt
| | - Ebtesam M. Al-Olayan
- School of Life Sciences, Keele University, Keele, United Kingdom
- Department of Zoology, King Saud University, Riyadh, Saudi Arabia
| | - Steven Lewis
- School of Life Sciences, Keele University, Keele, United Kingdom
| | - Holly Matthews
- School of Life Sciences, Keele University, Keele, United Kingdom
| | - Hilary Hurd
- School of Life Sciences, Keele University, Keele, United Kingdom
- * E-mail:
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41
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López ML, Vommaro R, Zalis M, de Souza W, Blair S, Segura C. Induction of cell death on Plasmodium falciparum asexual blood stages by Solanum nudum steroids. Parasitol Int 2010; 59:217-25. [DOI: 10.1016/j.parint.2010.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 01/15/2010] [Accepted: 02/04/2010] [Indexed: 11/15/2022]
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42
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Signaling mechanisms of apoptosis-like programmed cell death in unicellular eukaryotes. Comp Biochem Physiol B Biochem Mol Biol 2010; 155:341-53. [DOI: 10.1016/j.cbpb.2010.01.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 01/19/2010] [Accepted: 01/23/2010] [Indexed: 11/18/2022]
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43
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Jiang Q, Qin S, Wu QY. Genome-wide comparative analysis of metacaspases in unicellular and filamentous cyanobacteria. BMC Genomics 2010; 11:198. [PMID: 20334693 PMCID: PMC2853523 DOI: 10.1186/1471-2164-11-198] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 03/25/2010] [Indexed: 01/30/2023] Open
Abstract
Background Cyanobacteria are an ancient group of photoautotrophic prokaryotes with wide variations in genome size and ecological habitat. Metacaspases (MCAs) are cysteine proteinases that have sequence homology to caspases and play essential roles in programmed cell death (PCD). MCAs have been identified in several prokaryotes, fungi and plants; however, knowledge about cyanobacterial metacaspases still remains obscure. With the availability of sequenced genomes of 33 cyanobacteria, we perform a comparative analysis of metacaspases and explore their distribution, domain structure and evolution. Results A total of 58 putative MCAs were identified, which are abundant in filamentous diazotrophic cyanobacteria and Acaryochloris marina MBIC 11017 and absent in all Prochlorococcus and marine Synechococcus strains, except Synechococcus sp. PCC 7002. The Cys-His dyad of caspase superfamily is conserved, while mutations (Tyr in place of His and Ser/Asn/Gln/Gly instead of Cys) are also detected in some cyanobacteria. MCAs can be classified into two major families (α and β) based on the additional domain structure. Ten types and a total of 276 additional domains were identified, most of which involves in signal transduction. Apoptotic related NACHT domain was also found in two cyanobacterial MCAs. Phylogenetic tree of MCA catalytic P20 domains coincides well with the domain structure and the phylogenies based on 16s rRNA. Conclusions The existence and quantity of MCA genes in unicellular and filamentous cyanobacteria are a function of the genome size and ecological habitat. MCAs of family α and β seem to evolve separately and the recruitment of WD40 additional domain occurs later than the divergence of the two families. In this study, a general framework of sequence-structure-function connections for the metacaspases has been revealed, which may provide new targets for function investigation.
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Affiliation(s)
- Qiao Jiang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
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44
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Ojha M, Cattaneo A, Hugh S, Pawlowski J, Cox JA. Structure, expression and function of Allomyces arbuscula CDP II (metacaspase) gene. Gene 2010; 457:25-34. [PMID: 20214955 DOI: 10.1016/j.gene.2010.02.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 02/24/2010] [Accepted: 02/25/2010] [Indexed: 11/18/2022]
Abstract
Allomyces arbuscula, a primitive chytridiomycete fungus, has two Ca(2+)-dependent cysteine proteases, the CDP I and CDP II. We have cloned and analyzed the nucleotide sequence of CDP II gene and domain structure of the protein. Blast analysis of the sequence has shown that the protein belongs to a newly described member of caspase superfamily protein, the metacaspase, a CD clan of C14 family cysteine protease, we hence-forth name it as AMca 2 (Allomyces metacaspase 2). Southern hybridization studies have shown that the gene exists in a single copy per genome. The transcriptional analysis by Northern hybridization has confirmed our previous results that the protein is developmentally regulated, i.e. present in active growth phase but disappears during nutritional stress which also induces reproductive differentiation, indicating that the protein promotes cell growth, not death. The recombinant gene product expressed in Escherichiacoli has all the catalytic properties of native enzyme, i.e. sensitivity to protease inhibitors and substrate specificity. There is an absolute requirement of Ca(2+) for the activation of catalytic activity and the presence of R residue at the cleavage site (P1 position) in the substrate. The presence of a second basic residue, either R or K, in the P2 position strongly inhibits the catalytic activity which is stimulated by the presence of P and to a lesser extent G at this site. Peptide substrates with D at the cleavage site are not recognised and therefore not cleaved. The enzyme activity is inhibited by EDTA-EGTA, cysteine protease inhibitors and a specific peptide inhibitor Ac GVRCHCL TFA, but not by E64, although a potent inhibitor of cysteine proteases.
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Affiliation(s)
- Mukti Ojha
- Department of Biochemistry, University of Geneva, Sciences II, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland.
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45
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Atkinson HJ, Babbitt PC, Sajid M. The global cysteine peptidase landscape in parasites. Trends Parasitol 2009; 25:573-81. [PMID: 19854678 DOI: 10.1016/j.pt.2009.09.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 08/13/2009] [Accepted: 09/22/2009] [Indexed: 11/27/2022]
Abstract
The accumulation of sequenced genomes has expanded the already sizeable population of cysteine peptidases from parasites. Characterization of a few of these enzymes has ascribed key roles to peptidases in parasite life cycles and has also shed light on mechanisms of pathogenesis. Here we discuss recent observations on the physiological activities of cysteine peptidases of parasitic organisms, paired with a global view of all cysteine peptidases from the MEROPS database grouped by similarity. This snapshot of the landscape of parasite cysteine peptidases is complex and highly populated, suggesting that expansion of research beyond the few 'model' parasite peptidases is now timely.
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Affiliation(s)
- Holly J Atkinson
- UCSF Graduate Program in Biological and Medical Informatics, University of California San Francisco, San Francisco, CA 94158-2330, USA
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46
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The proteasome inhibitor epoxomicin has potent Plasmodium falciparum gametocytocidal activity. Antimicrob Agents Chemother 2009; 53:4080-5. [PMID: 19651911 DOI: 10.1128/aac.00088-09] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Malaria continues to be a major global health problem, but only a limited arsenal of effective drugs is available. None of the antimalarial compounds commonly used clinically kill mature gametocytes, which is the form of the parasite that is responsible for malaria transmission. The parasite that causes the most virulent human malaria, Plasmodium falciparum, has a 48-h asexual cycle, while complete sexual differentiation takes 10 to 12 days. Once mature, stage V gametocytes circulate in the peripheral blood and can be transmitted for more than a week. Consequently, if chemotherapy does not eliminate gametocytes, an individual continues to be infectious for several weeks after the clearance of asexual parasites. The work reported here demonstrates that nanomolar concentrations of the proteasome inhibitor epoxomicin effectively kill all stages of intraerythrocytic parasites but do not affect the viability of human or mouse cell lines. Twenty-four hours after treatment with 100 nM epoxomicin, the total parasitemia decreased by 78%, asexual parasites decreased by 86%, and gametocytes decreased by 77%. Seventy-two hours after treatment, no viable parasites remained in the 100 or 10 nM treatment group. Epoxomicin also blocked oocyst production in the mosquito midgut. In contrast, the cysteine protease inhibitors epoxysuccinyl-L-leucylamido-3-methyl-butane ethyl ester and N-acetyl-L-leucyl-L-leucyl-L-methioninal blocked hemoglobin digestion in early gametocytes but had no effect on later stages. Moreover, once the cysteine protease inhibitor was removed, sexual differentiation resumed. These findings provide strong support for the further development of proteasome inhibitors as antimalaria agents that are effective against asexual, sexual, and mosquito midgut stages of P. falciparum.
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47
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Arambage SC, Grant KM, Pardo I, Ranford-Cartwright L, Hurd H. Malaria ookinetes exhibit multiple markers for apoptosis-like programmed cell death in vitro. Parasit Vectors 2009; 2:32. [PMID: 19604379 PMCID: PMC2720949 DOI: 10.1186/1756-3305-2-32] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Accepted: 07/15/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A wide range of unicellular eukaryotes have now been shown to undergo a form of programmed cell death (PCD) that resembles apoptosis; exhibiting morphological and, in some cases, biochemical markers typical of metazoans. However, reports that sexual and asexual stages of malaria parasites exhibit these markers have been challenged. Here we use a rodent malaria model, Plasmodium berghei, to determine whether, and what proportion of cultured ookinetes show signs of apoptosis-like death and extend the study to examine ookinetes of Plasmodium falciparum in vivo. RESULTS Ookinetes displayed the following markers of PCD: loss of mitochondrial membrane potential, nuclear chromatin condensation, DNA fragmentation, translocation of phosphatidylserine to the outer surface of the cell membrane and caspase-like activity. The proportion of parasites expressing apoptosis markers rose with time, particularly when cultured in phosphate buffered saline. Some ookinetes positive for apoptosis markers also had compromised membranes, which could represent a late stage in the process. When these are included a similar proportion of ookinetes display each marker. Over 50% of P. falciparum ookinetes, removed from the mosquito midgut lumen 24 h post-infection, had nuclei containing fragmented DNA. CONCLUSION We have confirmed previous reports that Plasmodium ookinetes display multiple signs that suggest they die by a mechanism resembling apoptosis. This occurs in vivo and in vitro without experimental application of triggers. Our findings support the hypothesis that non-necrotic mechanisms of cell death evolved before the advent of multicellular organisms.
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Affiliation(s)
- Shashini C Arambage
- Institute of Science and Technology in Medicine, Centre for Applied Entomology and Parasitology, School of Life Sciences, Huxley Building, Keele University, Staffordshire, ST5 5BG, UK.
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Improved prediction of malaria degradomes by supervised learning with SVM and profile kernel. Genetica 2008; 136:189-209. [PMID: 19057851 DOI: 10.1007/s10709-008-9336-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Accepted: 11/17/2008] [Indexed: 10/21/2022]
Abstract
The spread of drug resistance through malaria parasite populations calls for the development of new therapeutic strategies. However, the seemingly promising genomics-driven target identification paradigm is hampered by the weak annotation coverage. To identify potentially important yet uncharacterized proteins, we apply support vector machines using profile kernels, a supervised discriminative machine learning technique for remote homology detection, as a complement to the traditional alignment based algorithms. In this study, we focus on the prediction of proteases, which have long been considered attractive drug targets because of their indispensable roles in parasite development and infection. Our analysis demonstrates that an abundant and complex repertoire is conserved in five Plasmodium parasite species. Several putative proteases may be important components in networks that mediate cellular processes, including hemoglobin digestion, invasion, trafficking, cell cycle fate, and signal transduction. This catalog of proteases provides a short list of targets for functional characterization and rational inhibitor design.
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Tremp AZ, Khater EI, Dessens JT. IMC1b is a putative membrane skeleton protein involved in cell shape, mechanical strength, motility, and infectivity of malaria ookinetes. J Biol Chem 2008; 283:27604-27611. [PMID: 18650444 PMCID: PMC2562075 DOI: 10.1074/jbc.m801302200] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Membrane skeletons are cytoskeletal elements that have important roles in
cell development, shape, and structural integrity. Malaria parasites encode a
conserved family of putative membrane skeleton proteins related to articulins.
One member, IMC1a, is expressed in sporozoites and localizes to the pellicle,
a unique membrane complex believed to form a scaffold onto which the ligands
and glideosome are arranged to mediate parasite motility and invasion. IMC1b
is a closely related structural paralogue of IMC1a, fostering speculation that
it could be functionally homologous but in a different invasive life stage.
Here we have generated genetically modified parasites that express IMC1b
tagged with green fluorescent protein, and we show that it is targeted
exclusively to the pellicle of ookinetes. We also show that IMC1b-deficient
ookinetes display abnormal cell shape, reduced gliding motility, decreased
mechanical strength, and reduced infectivity. These findings are consistent
with a membrane skeletal role of IMC1b and provide strong experimental support
for the view that membrane skeletons form an integral part of the pellicle of
apicomplexan zoites and function to provide rigidity to the pellicular
membrane complex. The similarities observed between the loss-of-function
phenotypes of IMC1a and IMC1b show that membrane skeletons of ookinetes and
sporozoites function in an overall similar way. However, the fact that
ookinetes and sporozoites do not use the same IMC1 protein implies that
different mechanical properties are required of their respective membrane
skeletons, likely reflecting the distinct environments in which these life
stages must operate.
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Affiliation(s)
- Annie Z Tremp
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom
| | - Emad I Khater
- Department of Entomology, Ain Shams University, Abbassia 11566, Cairo, Egypt
| | - Johannes T Dessens
- Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom.
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Chowdhury I, Tharakan B, Bhat GK. Caspases - an update. Comp Biochem Physiol B Biochem Mol Biol 2008; 151:10-27. [PMID: 18602321 DOI: 10.1016/j.cbpb.2008.05.010] [Citation(s) in RCA: 259] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 05/23/2008] [Accepted: 05/23/2008] [Indexed: 02/07/2023]
Abstract
Caspases belong to a family of highly conserved aspartate-specific cysteine proteases and are members of the interleukin-1beta-converting enzyme family, present in multicellular organisms. The caspase gene family consists of 15 mammalian members that are grouped into two major sub-families, namely inflammatory caspases and apoptotic caspases. The apoptotic caspases are further subdivided into two sub-groups, initiator caspases and executioner caspases. The caspases form a caspase-cascade system that plays the central role in the induction, transduction and amplification of intracellular apoptotic signals for cell fate determination, regulation of immunity, and cellular proliferation and differentiation. The substrates of apoptotic caspases have been associated with cellular dismantling, while inflammatory caspases mediate the proteolytic activation of inflammatory cytokines. The activation of this delicate caspase-cascade system and its functions are regulated by a variety of regulatory molecules, such as the inhibitor of apoptosis protein (IAP), FLICE, calpain, and Ca(2+). Based on the available literature we have reviewed and discussed the members of the caspase family, caspase-cascade system, caspase-regulating molecules and their apoptotic and non-apoptotic functions in cellular life and death. Also recent progress in the molecular structure and physiological role of non-mammalian caspases such as paracaspases, metacaspases and caspase-like-protease family members are included in relation to that of mammalian species.
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Affiliation(s)
- Indrajit Chowdhury
- Department of Obstetrics and Gynecology, Morehouse School of Medicine, 720 Westview Drive, SW., Atlanta, GA 30310, USA
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