1
|
Probst A, Nguyen TN, El-Sakkary N, Skinner D, Suzuki BM, Buckner FS, Gelb MH, Caffrey CR, Debnath A. Bioactivity of Farnesyltransferase Inhibitors Against Entamoeba histolytica and Schistosoma mansoni. Front Cell Infect Microbiol 2019; 9:180. [PMID: 31192168 PMCID: PMC6548881 DOI: 10.3389/fcimb.2019.00180] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/09/2019] [Indexed: 01/17/2023] Open
Abstract
The protozoan parasite Entamoeba histolytica can induce amebic colitis and amebic liver abscess. First-line drugs for the treatment of amebiasis are nitroimidazoles, particularly metronidazole. Metronidazole has side effects and potential drug resistance is a concern. Schistosomiasis, a chronic and painful infection, is caused by various species of the Schistosoma flatworm. There is only one partially effective drug, praziquantel, a worrisome situation should drug resistance emerge. As many essential metabolic pathways and enzymes are shared between eukaryotic organisms, it is possible to conceive of small molecule interventions that target more than one organism or target, particularly when chemical matter is already available. Farnesyltransferase (FT), the last common enzyme for products derived from the mevalonate pathway, is vital for diverse functions, including cell differentiation and growth. Both E. histolytica and Schistosoma mansoni genomes encode FT genes. In this study, we phenotypically screened E. histolytica and S. mansoni in vitro with the established FT inhibitors, lonafarnib and tipifarnib, and with 125 tipifarnib analogs previously screened against both the whole organism and/or the FT of Trypanosoma brucei and Trypanosoma cruzi. For E. histolytica, we also explored whether synergy arises by combining lonafarnib and metronidazole or lonafarnib with statins that modulate protein prenylation. We demonstrate the anti-amebic and anti-schistosomal activities of lonafarnib and tipifarnib, and identify 17 tipifarnib analogs with more than 75% growth inhibition at 50 μM against E. histolytica. Apart from five analogs of tipifarnib exhibiting activity against both E. histolytica and S. mansoni, 10 additional analogs demonstrated anti-schistosomal activity (severe degenerative changes at 10 μM after 24 h). Analysis of the structure-activity relationship available for the T. brucei FT suggests that FT may not be the relevant target in E. histolytica and S. mansoni. For E. histolytica, combination of metronidazole and lonafarnib resulted in synergism for growth inhibition. Also, of a number of statins tested, simvastatin exhibited moderate anti-amebic activity which, when combined with lonafarnib, resulted in slight synergism. Even in the absence of a definitive molecular target, identification of potent anti-parasitic tipifarnib analogs encourages further exploration while the synergistic combination of metronidazole and lonafarnib offers a promising treatment strategy for amebiasis.
Collapse
Affiliation(s)
- Alexandra Probst
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Thi N Nguyen
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Nelly El-Sakkary
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Danielle Skinner
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Brian M Suzuki
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Frederick S Buckner
- Division of Allergy and Infectious Diseases, Department of Medicine, Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, WA, United States
| | - Michael H Gelb
- Departments of Chemistry and Biochemistry, University of Washington, Seattle, WA, United States
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Anjan Debnath
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States
| |
Collapse
|
2
|
Ressurreição M, Elbeyioglu F, Kirk RS, Rollinson D, Emery AM, Page NM, Walker AJ. Molecular characterization of host-parasite cell signalling in Schistosoma mansoni during early development. Sci Rep 2016; 6:35614. [PMID: 27762399 PMCID: PMC5071895 DOI: 10.1038/srep35614] [Citation(s) in RCA: 17] [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: 06/14/2016] [Accepted: 10/04/2016] [Indexed: 02/04/2023] Open
Abstract
During infection of their human definitive host, schistosomes transform rapidly from free-swimming infective cercariae in freshwater to endoparasitic schistosomules. The 'somules' next migrate within the skin to access the vasculature and are surrounded by host molecules that might activate intracellular pathways that influence somule survival, development and/or behaviour. However, such 'transactivation' by host factors in schistosomes is not well defined. In the present study, we have characterized and functionally localized the dynamics of protein kinase C (PKC) and extracellular signal-regulated kinase (ERK) activation during early somule development in vitro and demonstrate activation of these protein kinases by human epidermal growth factor, insulin, and insulin-like growth factor I, particularly at the parasite surface. Further, we provide evidence that support the existence of specialized signalling domains called lipid rafts in schistosomes and propose that correct signalling to ERK requires proper raft organization. Finally, we show that modulation of PKC and ERK activities in somules affects motility and reduces somule survival. Thus, PKC and ERK are important mediators of host-ligand regulated transactivation events in schistosomes, and represent potential targets for anti-schistosome therapy aimed at reducing parasite survival in the human host.
Collapse
Affiliation(s)
- Margarida Ressurreição
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, KT1 2EE, United Kingdom
| | - Firat Elbeyioglu
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, KT1 2EE, United Kingdom
| | - Ruth S. Kirk
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, KT1 2EE, United Kingdom
| | - David Rollinson
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Aidan M. Emery
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, United Kingdom
| | - Nigel M. Page
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, KT1 2EE, United Kingdom
| | - Anthony J. Walker
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, KT1 2EE, United Kingdom
| |
Collapse
|
3
|
Lu Z, Sessler F, Holroyd N, Hahnel S, Quack T, Berriman M, Grevelding CG. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay. Sci Rep 2016; 6:31150. [PMID: 27499125 PMCID: PMC4976352 DOI: 10.1038/srep31150] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 07/12/2016] [Indexed: 12/25/2022] Open
Abstract
As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects.
Collapse
Affiliation(s)
- Zhigang Lu
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Florian Sessler
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Nancy Holroyd
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Steffen Hahnel
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Thomas Quack
- BFS, Institute of Parasitology, Justus-Liebig-University, Giessen, Germany
| | - Matthew Berriman
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | | |
Collapse
|
4
|
Ressurreição M, De Saram P, Kirk RS, Rollinson D, Emery AM, Page NM, Davies AJ, Walker AJ. Protein kinase C and extracellular signal-regulated kinase regulate movement, attachment, pairing and egg release in Schistosoma mansoni. PLoS Negl Trop Dis 2014; 8:e2924. [PMID: 24921927 PMCID: PMC4055629 DOI: 10.1371/journal.pntd.0002924] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 04/19/2014] [Indexed: 01/22/2023] Open
Abstract
Protein kinases C (PKCs) and extracellular signal-regulated kinases (ERKs) are evolutionary conserved cell signalling enzymes that coordinate cell function. Here we have employed biochemical approaches using ‘smart’ antibodies and functional screening to unravel the importance of these enzymes to Schistosoma mansoni physiology. Various PKC and ERK isotypes were detected, and were differentially phosphorylated (activated) throughout the various S. mansoni life stages, suggesting isotype-specific roles and differences in signalling complexity during parasite development. Functional kinase mapping in adult worms revealed that activated PKC and ERK were particularly associated with the adult male tegument, musculature and oesophagus and occasionally with the oesophageal gland; other structures possessing detectable activated PKC and/or ERK included the Mehlis' gland, ootype, lumen of the vitellaria, seminal receptacle and excretory ducts. Pharmacological modulation of PKC and ERK activity in adult worms using GF109203X, U0126, or PMA, resulted in significant physiological disturbance commensurate with these proteins occupying a central position in signalling pathways associated with schistosome muscular activity, neuromuscular coordination, reproductive function, attachment and pairing. Increased activation of ERK and PKC was also detected in worms following praziquantel treatment, with increased signalling associated with the tegument and excretory system and activated ERK localizing to previously unseen structures, including the cephalic ganglia. These findings support roles for PKC and ERK in S. mansoni homeostasis, and identify these kinase groups as potential targets for chemotherapeutic treatments against human schistosomiasis, a neglected tropical disease of enormous public health significance. Parasitic blood flukes, also called schistosomes, cause human schistosomiasis, a neglected tropical disease and major public health problem in developing countries, especially sub-Saharan Africa. Sustainable control of schistosomiasis is difficult, mainly because the complex life cycle of the parasite involves a freshwater snail host, and the ability of the parasite to evade the immune response of the human host and to survive for many years. Little is yet known about the cellular mechanisms in schistosomes and how they regulate parasite homeostasis, development and behaviour. In this paper, the nature of intracellular signalling by protein kinases C (PKCs) and extracellular signal-regulated kinases (ERKs) in schistosomes is studied and these proteins are found to be vital for the coordination of processes fundamental to parasite survival, such as muscular activity and reproductive function. Our results contribute to an understanding of molecular events regulating schistosome function and identify PKCs and ERKs as possible targets for the development of new chemotherapeutic treatments against schistosomiasis.
Collapse
Affiliation(s)
- Margarida Ressurreição
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
- Wolfson Wellcome Biomedical Laboratories, Life Sciences Department, Natural History Museum, London, United Kingdom
| | - Paulu De Saram
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
- Wolfson Wellcome Biomedical Laboratories, Life Sciences Department, Natural History Museum, London, United Kingdom
| | - Ruth S. Kirk
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Life Sciences Department, Natural History Museum, London, United Kingdom
| | - Aidan M. Emery
- Wolfson Wellcome Biomedical Laboratories, Life Sciences Department, Natural History Museum, London, United Kingdom
| | - Nigel M. Page
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
| | - Angela J. Davies
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
| | - Anthony J. Walker
- Molecular Parasitology Laboratory, School of Life Sciences, Kingston University, Kingston upon Thames, Surrey, United Kingdom
- * E-mail:
| |
Collapse
|
5
|
de Andrade LF, Mourão MDM, Geraldo JA, Coelho FS, Silva LL, Neves RH, Volpini A, Machado-Silva JR, Araujo N, Nacif-Pimenta R, Caffrey CR, Oliveira G. Regulation of Schistosoma mansoni development and reproduction by the mitogen-activated protein kinase signaling pathway. PLoS Negl Trop Dis 2014; 8:e2949. [PMID: 24945272 PMCID: PMC4063740 DOI: 10.1371/journal.pntd.0002949] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 05/04/2014] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Protein kinases are proven targets for drug development with an increasing number of eukaryotic Protein Kinase (ePK) inhibitors now approved as drugs. Mitogen-activated protein kinase (MAPK) family members connect cell-surface receptors to regulatory targets within cells and influence a number of tissue-specific biological activities such as cell proliferation, differentiation and survival. However, the contributions of members of the MAPK pathway to schistosome development and survival are unclear. METHODOLOGY/PRINCIPAL FINDINGS We employed RNA interference (RNAi) to elucidate the functional roles of five S. mansoni genes (SmCaMK2, SmJNK, SmERK1, SmERK2 and SmRas) involved in MAPK signaling pathway. Mice were injected with post-infective larvae (schistosomula) subsequent to RNAi and the development of adult worms observed. The data demonstrate that SmJNK participates in parasite maturation and survival of the parasites, whereas SmERK are involved in egg production as infected mice had significantly lower egg burdens with female worms presenting underdeveloped ovaries. Furthermore, it was shown that the c-fos transcription factor was overexpressed in parasites submitted to RNAi of SmERK1, SmJNK and SmCaMK2 indicating its putative involvement in gene regulation in this parasite's MAPK signaling cascade. CONCLUSIONS We conclude that MAPKs proteins play important roles in the parasite in vivo survival, being essential for normal development and successful survival and reproduction of the schistosome parasite. Moreover SmERK and SmJNK are potential targets for drug development.
Collapse
Affiliation(s)
- Luiza Freire de Andrade
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Marina de Moraes Mourão
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Juliana Assis Geraldo
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Fernanda Sales Coelho
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Larissa Lopes Silva
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Renata Heisler Neves
- Biologia Parasitária, Departamento de Ensino, Pavilhão Arthur Neiva, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Helmintologia Romero Lascasas Porto, Departamento de Patologia e Laboratórios, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Angela Volpini
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - José Roberto Machado-Silva
- Laboratório de Helmintologia Romero Lascasas Porto, Departamento de Patologia e Laboratórios, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Neusa Araujo
- Laboratório de Esquistossomose Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz - FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Rafael Nacif-Pimenta
- Laboratório de Entomologia Médica, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz - FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, California Institute for Quantitative Biosciences and the Department of Pathology, University of California, San Francisco, San Francisco, California, United States of America
| | - Guilherme Oliveira
- Grupo de Genômica e Biologia Computacional, Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais and Centro de Excelência em Bioinformática- CEBio, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz – FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| |
Collapse
|
6
|
Rojo-Arreola L, Long T, Asarnow D, Suzuki BM, Singh R, Caffrey CR. Chemical and genetic validation of the statin drug target to treat the helminth disease, schistosomiasis. PLoS One 2014; 9:e87594. [PMID: 24489942 PMCID: PMC3906178 DOI: 10.1371/journal.pone.0087594] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 12/21/2013] [Indexed: 12/26/2022] Open
Abstract
The mevalonate pathway is essential in eukaryotes and responsible for a diversity of fundamental synthetic activities. 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is the rate-limiting enzyme in the pathway and is targeted by the ubiquitous statin drugs to treat hypercholesterolemia. Independent reports have indicated the cidal effects of statins against the flatworm parasite, S. mansoni, and the possibility that SmHMGR is a useful drug target to develop new statin-based anti-schistosome therapies. For six commercially available statins, we demonstrate concentration- and time-dependent killing of immature (somule) and adult S. mansoni in vitro at sub-micromolar and micromolar concentrations, respectively. Cidal activity trends with statin lipophilicity whereby simvastatin and pravastatin are the most and least active, respectively. Worm death is preventable by excess mevalonate, the product of HMGR. Statin activity against somules was quantified both manually and automatically using a new, machine learning-based automated algorithm with congruent results. In addition, to chemical targeting, RNA interference (RNAi) of HMGR also kills somules in vitro and, again, lethality is blocked by excess mevalonate. Further, RNAi of HMGR of somules in vitro subsequently limits parasite survival in a mouse model of infection by up to 80%. Parasite death, either via statins or specific RNAi of HMGR, is associated with activation of apoptotic caspase activity. Together, our genetic and chemical data confirm that S. mansoni HMGR is an essential gene and the relevant target of statin drugs. We discuss our findings in context of a potential drug development program and the desired product profile for a new schistosomiasis drug.
Collapse
Affiliation(s)
- Liliana Rojo-Arreola
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Thavy Long
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Dan Asarnow
- Department of Computer Science, San Francisco State University, San Francisco, California, United States of America
| | - Brian M. Suzuki
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Rahul Singh
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- Department of Computer Science, San Francisco State University, San Francisco, California, United States of America
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
| |
Collapse
|
7
|
Characterization of potential drug targets farnesyl diphosphate synthase and geranylgeranyl diphosphate synthase in Schistosoma mansoni. Antimicrob Agents Chemother 2013; 57:5969-76. [PMID: 24041901 DOI: 10.1128/aac.00699-13] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Schistosomiasis affects over 200 million people worldwide, with over 200,000 deaths annually. Currently, praziquantel is the only drug available against schistosomiasis. We report here that Schistosoma mansoni farnesyl diphosphate synthase (SmFPPS) and geranylgeranyl diphosphate synthase (SmGGPPS) are potential drug targets for the treatment of schistosomiasis. We expressed active, recombinant SmFPPS and SmGGPPS for subsequent kinetic characterization and testing against a variety of bisphosphonate inhibitors. Recombinant SmFPPS was found to be a soluble 44.2-kDa protein, while SmGGPPS was a soluble 38.3-kDa protein. Characterization of the substrate utilization of the two enzymes indicates that they have overlapping substrate specificities. Against SmFPPS, several bisphosphonates had 50% inhibitory concentrations (IC50s) in the low micromolar to nanomolar range; these inhibitors had significantly less activity against SmGGPPS. Several lipophilic bisphosphonates were active against ex vivo adult worms, with worm death occurring over 4 to 6 days. These results indicate that FPPS and GGPPS could be of interest in the context of the emerging resistance to praziquantel in schistosomiasis therapy.
Collapse
|
8
|
Abstract
SIGNIFICANCE Cysteine residues of proteins participate in the catalysis of biochemical reactions, are crucial for redox reactions, and influence protein structure by the formation of disulfide bonds. Covalent posttranslational modifications (PTMs) of cysteine residues are important mediators of redox regulation and signaling by coupling protein activity to the cellular redox state, and moreover influence stability, function, and localization of proteins. A diverse group of protozoan and metazoan parasites are a major cause of diseases in humans, such as malaria, African trypanosomiasis, leishmaniasis, toxoplasmosis, filariasis, and schistosomiasis. RECENT ADVANCES Human parasites undergo dramatic morphological and metabolic changes while they pass complex life cycles and adapt to changing environments in host and vector. These processes are in part regulated by PTMs of parasitic proteins. In human parasites, posttranslational cysteine modifications are involved in crucial cellular events such as signal transduction (S-glutathionylation and S-nitrosylation), redox regulation of proteins (S-glutathionylation and S-nitrosylation), protein trafficking and subcellular localization (palmitoylation and prenylation), as well as invasion into and egress from host cells (palmitoylation). This review focuses on the occurrence and mechanisms of these cysteine modifications in parasites. CRITICAL ISSUES Studies on cysteine modifications in human parasites are so far largely based on in vitro experiments. FUTURE DIRECTIONS The in vivo regulation of cysteine modifications and their role in parasite development will be of great interest in order to understand redox signaling in parasites.
Collapse
Affiliation(s)
- Esther Jortzik
- Interdisciplinary Research Center, Justus Liebig University, Giessen, Germany
| | | | | |
Collapse
|
9
|
Bahia D, Andrade LF, Ludolf F, Mortara RA, Oliveira G. Protein tyrosine kinases in Schistosoma mansoni. Mem Inst Oswaldo Cruz 2008; 101 Suppl 1:137-43. [PMID: 17308761 DOI: 10.1590/s0074-02762006000900022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Accepted: 06/26/2006] [Indexed: 11/22/2022] Open
Abstract
The identification and description of signal transduction molecules and mechanisms are essential to elucidate Schistosoma mansoni host-parasite interactions and parasite biology. This mini review focuses on recent advancements in the study of signalling molecules and transduction mechanisms in S. mansoni, drawing special attention to the recently identified and characterised protein tyrosine kinases of S. mansoni.
Collapse
Affiliation(s)
- Diana Bahia
- Centro de Pesquisas René Rachou-Fiocruz, Av. Augusto de Lima 1715, Barro Preto, 31190-002 Belo Horizonte, MG, Brazil.
| | | | | | | | | |
Collapse
|
10
|
Knobloch J, Beckmann S, Burmeister C, Quack T, Grevelding CG. Tyrosine kinase and cooperative TGFβ signaling in the reproductive organs of Schistosoma mansoni. Exp Parasitol 2007; 117:318-36. [PMID: 17553494 DOI: 10.1016/j.exppara.2007.04.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2007] [Revised: 04/06/2007] [Accepted: 04/16/2007] [Indexed: 10/23/2022]
Abstract
Drug-induced suppression of female schistosome sexual maturation is an auspicious strategy to combat schistosomiasis since the eggs are the causative agent. The establishment of drug targets requires knowledge about the molecular mechanisms that regulate the development of the female reproductive organs, which include vitellarium and ovary. This review summarizes recent studies suggesting tyrosine kinases as important factors for the regulation of female gonad development. In this context, especially cytoplasmatic tyrosine kinases of the Src class seem to play dominant roles. Moreover, experimental data and theoretical concepts are provided supporting a crosstalk between tyrosine kinase and TGFbeta signaling in the production of vitellocytes. Finally, we take advantage from the schistosome genome project to propose a model for the regulation of vitelline-cell production and differentiation.
Collapse
Affiliation(s)
- Jürgen Knobloch
- Institute for Animal Developmental and Molecular Biology, Heinrich-Heine-University, D-40225 Düsseldorf, Germany.
| | | | | | | | | |
Collapse
|
11
|
Dissous C, Ahier A, Khayath N. Protein tyrosine kinases as new potential targets against human schistosomiasis. Bioessays 2007; 29:1281-8. [DOI: 10.1002/bies.20662] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
12
|
Protein Prenylation: An (Almost) Comprehensive Overview on Discovery History, Enzymology, and Significance in Physiology and Disease. MONATSHEFTE FUR CHEMIE 2006. [DOI: 10.1007/s00706-006-0534-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
13
|
Wang L, Yang Z, Li Y, Yu F, Brindley PJ, McManus DP, Wei D, Han Z, Feng Z, Li Y, Hu W. Reconstruction and in silico analysis of the MAPK signaling pathways in the human blood fluke,Schistosoma japonicum. FEBS Lett 2006; 580:3677-86. [PMID: 16765950 DOI: 10.1016/j.febslet.2006.05.055] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 05/17/2006] [Accepted: 05/24/2006] [Indexed: 12/22/2022]
Abstract
At present, little is known about signal transduction mechanisms in schistosomes, which cause the disease of schistosomiasis. The mitogen-activated protein kinase (MAPK) signaling pathways, which are evolutionarily conserved from yeast to Homo sapiens, play key roles in multiple cellular processes. Here, we reconstructed the hypothetical MAPK signaling pathways in Schistosoma japonicum and compared the schistosome pathways with those of model eukaryote species. We identified 60 homologous components in the S. japonciumMAPK signaling pathways. Among these, 27 were predicted to be full-length sequences. Phylogenetic analysis of these proteins confirmed the evolutionary conservation of the MAPK signaling pathways. Remarkably, we identified S. japonicum homologues of GTP-binding protein beta and alpha-I subunits in the yeast mating pathway, which might be involved in the regulation of different life stages and female sexual maturation processes as well in schistosomes. In addition, several pathway member genes, including ERK, JNK, Sja-DSP, MRAS and RAS, were determined through quantitative PCR analysis to be expressed in a stage-specific manner, with ERK, JNK and their inhibitor Sja-DSP markedly upregulated in adult female schistosomes.
Collapse
Affiliation(s)
- Lili Wang
- State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, 130 Mei-long Road, Shanghai 200237, PR China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Dissous C, Khayath N, Vicogne J, Capron M. Growth factor receptors in helminth parasites: Signalling and host-parasite relationships. FEBS Lett 2006; 580:2968-75. [PMID: 16579990 DOI: 10.1016/j.febslet.2006.03.046] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Accepted: 03/12/2006] [Indexed: 11/29/2022]
Abstract
Parasitic helminths remain major pathogens of both humans and animals throughout the world. The success of helminth infections depends on the capacity of the parasite to counteract host immune responses but also to exploit host-derived signal molecules for its development. Recent progress has been made in the characterization of growth factor receptors of various nematode and flatworm parasites with the demonstration that transforming growth factor beta (TGF-beta), epidermal growth factor (EGF) and insulin receptor signalling pathways are conserved in helminth parasites and potentially implicated in the host-parasite molecular dialogue and parasite development.
Collapse
Affiliation(s)
- Colette Dissous
- Unité Inserm 547, Institut Pasteur de Lille, 1 Rue du Pr. Calmette, 59019 Lille Cedex, France.
| | | | | | | |
Collapse
|
15
|
Hoffmann KF. An historical and genomic view of schistosome conjugal biology with emphasis on sex-specific gene expression. Parasitology 2005; 128 Suppl 1:S11-22. [PMID: 16454894 DOI: 10.1017/s0031182004006213] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The genetic programmes associated with the sexual biology of dioecious schistosomes remain a critically important but significantly understudied area of parasitology. Throughout the last four decades, progress has been slow in describing the gross antigenic and proteomic differences linked to sexually mature schistosomes and in characterizing some of the sex-associated transcripts and regulatory mechanisms induced during developmental maturation. These investigations have been severely hindered by the lack of complete EST/genomic information, as well as corresponding post- and functional-genomic tools for studying these pathogenic parasites. As near complete transcriptomes forSchistosoma japonicumandS. mansonihave recently been reported, and both DNA microarrays and post-transcriptional gene silencing have been applied to schistosomes, the tools and techniques for the high-throughput identification and characterization of transcripts involved in conjugal biology are now readily available. Here, an historical review is presented that summarizes some of the most significant findings associated with schistosome sex and sexual maturation during the last several decades. Following this discussion is a current overview of some modern day genomic approaches used to study schistosomes, which illustrates how major advances in the field of conjugal biology will be achieved.
Collapse
Affiliation(s)
- K F Hoffmann
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, UK.
| |
Collapse
|
16
|
Kapp K, Knobloch J, Schüssler P, Sroka S, Lammers R, Kunz W, Grevelding CG. The Schistosoma mansoni Src kinase TK3 is expressed in the gonads and likely involved in cytoskeletal organization. Mol Biochem Parasitol 2005; 138:171-82. [PMID: 15555729 DOI: 10.1016/j.molbiopara.2004.07.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2004] [Revised: 07/23/2004] [Accepted: 07/31/2004] [Indexed: 10/26/2022]
Abstract
Cytoplasmic protein tyrosine kinases of the Src family play a pivotal role in the regulation of cellular processes including proliferation and differentiation. Among other functions, Src kinases are involved in regulating the cell architecture. In an approach to identify protein tyrosine kinases from the medically important parasite Schistosoma mansoni, we isolated the TK3 gene by degenerate primer PCR and cDNA library screening. Sequencing of the complete cDNA and data-base analyses indicated that TK3 is a Src family kinase. Its predicted size of 71 kDa was confirmed by Western blot analysis. Southern blot analysis showed that TK3 is a single-copy gene, and Northern blot and RT-PCR experiments indicated its expression in both sexes and throughout development. Localization studies by in situ hybridization and immunolocalization revealed that TK3 is predominantly expressed in the reproductive organs such as the testes of the male and the ovary as well as the vitellarium of the female. Its enzymatic activity was confirmed by functional analyses. In transient transfection experiments with HEK293 cells, TK3 phosphorylated the well-known Src-kinase substrate p130 Cas, an intracellular scaffolding protein. Yeast two-hybrid screenings in a heterologous invertebrate system identified dAbi, vinculin and tubulin as binding partners, representing molecules that fulfill functions in the cell architecture of many organisms. These findings suggest that TK3 may play a role in signal transduction pathways organizing the cytoskeleton in the gonads of schistosomes.
Collapse
Affiliation(s)
- Katja Kapp
- Institut für Genetik, Genetische Parasitologie und Biologisch-Medizinisches-Forschungszentrum, Universitätsstr. 1, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | | | | | | | | | | | | |
Collapse
|
17
|
Spiliotis M, Tappe D, Brückner S, Mösch HU, Brehm K. Molecular cloning and characterization of Ras- and Raf-homologues from the fox-tapeworm Echinococcus multilocularis. Mol Biochem Parasitol 2005; 139:225-37. [PMID: 15664657 DOI: 10.1016/j.molbiopara.2004.11.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Accepted: 11/03/2004] [Indexed: 11/26/2022]
Abstract
To better understand growth regulation in the human parasitic cestode Echinococcus multilocularis, we have cloned and characterized the parasite's orthologues of the key regulatory factors Ras and Raf. Using a degenerative PCR approach a gene, emras, was identified whose gene product, EmRas, showed high homology (79% identical residues) to human Ras and contained all amino acid residues which are characteristic for this subfamily of small GTPases at the corresponding positions. Recombinantly expressed EmRas bound GTP and was farnesylated, but not geranyl-geranylated, by Echinococcus lysate in an in vitro prenylation assay. Furthermore, upon expression in yeast, emras was able to functionally complement the Saccharomyces orthologue RAS2 in an invasive growth assay. In Western blot analyses using an anti-EmRas antibody, the Echinococcus factor could be detected in lysates of the larval stages metacestode and protoscolex. By immune-histochemistry, EmRas was shown to localize to the germinal layer of the metacestode and to tegumental structures of the protoscolex, particularly around the rostellum and the sucker regions. In addition, we fully characterized the gene emraf whose product, EmRaf, displayed considerable homology to mammalian Raf-kinases and orthologous factors from Drosophila and Caenorhabditis elegans. emraf was co-expressed with emras in the larval stages metacestode and protoscolex during in vitro cultivation and during an infection of the intermediate host as assessed by RT-PCR experiments. The emraf gene was composed of nine exons and eight introns and shared four highly conserved exon-intron boundaries with the human gene encoding Raf-1, suggesting that both genes derived from a common evolutionary ancestor. Southern blot hybridizations demonstrated that emraf is a single copy gene. Using the yeast two-hybrid system, EmRaf was shown to interact with EmRas, but not with EmRal, a previously characterized orthologue of mammalian Ral GTPases. This is the first characterization of a Ras orthologue from a cestode and the first report on a Raf-like kinase from a platyhelminth. The data presented herein will form a solid basis for further investigations on Echinococcus signaling systems that are involved in growth control and development of the parasite.
Collapse
Affiliation(s)
- Markus Spiliotis
- Institute of Hygiene and Microbiology, Julius-Maximilians University, D-97080 Würzburg, Germany
| | | | | | | | | |
Collapse
|
18
|
Spiliotis M, Brehm K. Echinococcus multilocularis: identification and molecular characterization of a Ral-like small GTP-binding protein. Exp Parasitol 2004; 107:163-72. [PMID: 15363942 DOI: 10.1016/j.exppara.2004.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2003] [Revised: 04/02/2004] [Accepted: 05/27/2004] [Indexed: 11/24/2022]
Abstract
In mammals, Ral (Ras-like) GTPases have been implicated in the regulation of several cellular key processes such as oncogenic transformation, endocytosis, and actin-cytoskeleton dynamics. Here we provide, for the first time, molecular data on a Ral homologue from a parasitic helminth. We have cloned and characterized the complete cDNA molecule and the chromosomal locus encoding a novel GTP binding protein, EmRal, of the human parasite Echinococcus multilocularis. The encoded protein contained all highly conserved amino acid residues of the protein family at corresponding positions and shared significant sequence homologies with human RalA (53% identity) and RalB (54%). Upon heterologous expression of EmRal in Escherichia coli, the recombinant protein was able to bind GTP, thus indicating functionality of the Echinococcus factor. Using an in vitro prenylation assay, the purified protein was shown to be geranylgernylated, but not farnesylated, in both rabbit reticulocyte and Echinococcus cell extracts. The EmRal mRNA was found to be processed via trans-splicing and, using RT-PCR and virtual Northern blot experiments, expression of the factor could be demonstrated for the larval stages metacestode and protoscolex during an infection of the intermediate host. The data presented herein provide a solid basis for further investigations on Ras-Ral signaling mechanisms in Echinococcus.
Collapse
Affiliation(s)
- Markus Spiliotis
- Institute of Hygiene and Microbiology, University of Würzburg, Josef-Schneider-Strasse 2, D-97080, Germany
| | | |
Collapse
|
19
|
Abstract
Schistosome parasites are muticellular eucaryotic organisms with a complex life cycle that involves mammalian and snail hosts. Unlike other trematode parasites, schistosomes (along with the Didymozoidae) have evolved separate sexes or dioecy. Sex is determined by a chromosomal mechanism. The dioecious state created an opportunity for the sexes to play a role in schistosome evolution that has resulted in an interesting interplay between the sexes. The classical observation, made more than 50 years ago, is that female schistosomes do not develop unless a male worm is present. Studies up through the 1990s focused on dissecting the role of the sexes in mate attraction, mate choice, mating behavior, female growth, female reproductive development, egg production, and other sex-evolved functions. In the mid-1980s, studies began to address the molecular events of male–female interactions. The classic morphological observation that female schistosomes do not complete reproductive development unless a male worm is present has been redefined in molecular terms. The male by an unknown mechanism transduces a signal that regulates female gene expression in a stage-, tissue-, and temporal-specific manner. A number of female-specific genes have been identified, along with signaling pathways and nuclear receptors, that play a role in female reproductive development. In addition, a number of host factors such as cytokines have also been demonstrated to affect adult male and female development and egg production. This review focuses on the biological interactions of the male and female schistosome and the role of parasite and host factors in these interactions as they contribute to the life cycle of Schistosoma mansoni.
Collapse
|
20
|
Osman A, Niles EG, LoVerde PT. Expression of functional Schistosoma mansoni Smad4: role in Erk-mediated transforming growth factor beta (TGF-beta) down-regulation. J Biol Chem 2003; 279:6474-86. [PMID: 14630909 DOI: 10.1074/jbc.m310949200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Members of the transforming growth factor (TGF)-beta superfamily play pivotal roles in cell migration, differentiation, adhesion, pattern formation, and apoptosis. The family of Smad proteins acts as intracellular signal transducers of TGF-beta and related peptides. Smad4, a common mediator Smad (co-Smad), performs a central role in transmitting signals from TGF-beta, BMP, and activins. Schistosoma mansoni receptor-regulated Smad1 and SmSmad2 were previously identified and shown to act in TGF-beta signaling. Herein, we report the identification and characterization of a Smad4 homologue from S. mansoni and provide details about its role in mediation and down-regulation of TGF-beta signaling in schistosomes. In order to identify the schistosome co-Smad, we designed degenerate primers based on the sequence of the conserved MH1/MH2 domains of Smad4 proteins, which were used in PCR to amplify a 137-bp PCR product. A S. mansoni adult worm pair cDNA library was screened resulting in the isolation of a cDNA clone that encodes a 738 amino acid protein (SmSmad4). SmSmad4 was shown to interact with schistosome R-Smads (SmSmad1 and SmSmad2) in vivo and in vitro. The interaction with SmSmad2 was dependent on the receptor-mediated phosphorylation of SmSmad2. In addition, several potential phosphorylation sites for Erk1/2 kinases were identified in the SmSmad4 linker region and shown to be phosphorylated in vitro by an active mutant of mammalian Erk2. Furthermore, Erk-mediated phosphorylation of SmSmad4 decreased its interaction with the receptor-activated form of SmSmad2, in vitro. SmSmad4 was shown to complement a human Smad4 deficiency through the restoration of TGF-beta-responsiveness in MDA-MB-468 breast cancer cells.
Collapse
Affiliation(s)
- Ahmed Osman
- Department of Microbiology and Immunology and Witebsky Center for Microbial Pathogenesis and Immunology, School of Medicine, State University of New York, Buffalo, New York 14214, USA
| | | | | |
Collapse
|
21
|
Maurer-Stroh S, Washietl S, Eisenhaber F. Protein prenyltransferases: anchor size, pseudogenes and parasites. Biol Chem 2003; 384:977-89. [PMID: 12956414 DOI: 10.1515/bc.2003.110] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Lipid modification of eukaryotic proteins by protein prenyltransferases is required for critical signaling pathways, cell cycle progression, cytoskeleton remodeling, induction of apoptosis and vesicular trafficking. This review analyzes the influence of distinct states of sequential posttranslational processing that can be obtained after single or double prenylation, reversible palmitoylation, proteolytic cleavage of the C-terminus and possible reversible carboxymethylation. This series of modifications, as well as the exact length of the prenyl anchor, are determinants in protein-membrane and specific protein-protein interactions of protein prenyltransferase substrates. Furthermore, the occurrence and distribution of pseudogenes of protein prenyltransferase subunits are discussed. Besides being developed as anti-cancer agents, prenyltransferase inhibitors are effective against an increasing number of parasitic diseases. Extensive screens for protein prenyltransferases in genomic data of fungal and protozoan pathogens unveil a series of new pharmacologic targets for prenyltransferase inhibition, including the parasites Brugia malayi, Onchocerca volvulus, Aspergillus nidulans, Pneumocystis carinii, Entamoeba histolytica, Strongyloides stercoralis, Trichinella spiralis and Cryptosporidium parvum.
Collapse
|
22
|
Vermeire JJ, Osman A, LoVerde PT, Williams DL. Characterisation of a Rho homologue of Schistosoma mansoni. Int J Parasitol 2003; 33:721-31. [PMID: 12814652 DOI: 10.1016/s0020-7519(03)00046-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The development and survival of the helminth parasite, Schistosoma mansoni, is dependent on its ability to interpret signals from its environment. Currently, little is known about signal transduction in schistosomes. Rho is a member of a super-family of small GTP-binding proteins. Rho is involved in a number of cell signalling pathways with effects on actin cytoskeleton organisation, gene transcription, cell cycle progression, and membrane trafficking. We have cloned an S. mansoni protein (Rho1) that has 71-75% identity and approximately 85% similarity with human Rho A, B, and C proteins. We have optimised expression of recombinant S. mansoni Rho1 protein in Escherichia coli by co-expression with rare tRNAs. Western blot analysis results showed expression of Rho1 protein in adult worm stages especially female worms. In vitro prenylation of recombinant S. mansoni Rho1 determined that, similar to Rho from other organisms, Rho1 is geranynlgeranylated but not farnesylated. A search of the gene database indicates that Rho GTPases exist as a small family in S. mansoni including orthologues of Rho, Cdc42, and Rac. These data suggest that S. mansoni Rho1 plays a role in signalling in adult worms, especially females.
Collapse
Affiliation(s)
- Jon J Vermeire
- Department of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | | | | | | |
Collapse
|
23
|
Santos TM, Machado CR, Franco GR, Pena SDJ. Characterization and comparative functional analysis in yeast of a Schistosoma mansoni Rho1 GTPase gene. Mol Biochem Parasitol 2002; 125:103-12. [PMID: 12467978 DOI: 10.1016/s0166-6851(02)00218-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Low-molecular weight GTP-binding proteins (LMWGPs) of the Ras superfamily are believed to play a role in Schistosoma mansoni female development and egg production. Here we describe the characterization of a novel S. mansoni gene (SMRHO1), highly homologous to Rho-type LMWGPs from several other organisms and encoding a polypeptide with 193 amino acids and an estimated molecular mass of 21.8 kDa. SMRHO1 complemented a Saccharomyces cerevisiae rho1 null mutant strain even in restrictive temperature and calcium concentration, in contrast with the human RHOA GTPase that was not able to provide complementation in such conditions. Comparison of the amino acid sequence of the alpha3-helix loop7 regions of the two proteins allowed the identification of the proline 96 and threonine 100 amino acid residues of human RHOA as the most probable determinants of the complementation differences. We generated SMRHO1 mutants (smrho1(E97P), smrho1(L101T) and smrho1(E97P,) L101T) by site directed mutagenesis and reproduced the conditional lethality phenotype at high temperature, providing strong evidence that the related amino acid positions (Gln(101) and Ile(105)) in the Rho1 GTPase are indeed important for regulation of the cell wall synthesis performed by this protein in yeast. The observation that specific amino acid positions seem to be important for the different functions performed by the Rho GTPases leads to the idea that SMRHO1 might be a useful target in the development of new anti-schistosomiasis drugs, although it does share high sequence homology with the human RhoA GTPase.
Collapse
Affiliation(s)
- Túlio Marcos Santos
- Laboratório de Genética Bioquímica, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Caixa Postal 486, Belo Horizonte CEP 30161-970, MG, Brazil
| | | | | | | |
Collapse
|
24
|
LoVerde PT. Presidential address. Sex and schistosomes: an interesting biological interplay with control implications. J Parasitol 2002; 88:3-13. [PMID: 12053976 DOI: 10.1645/0022-3395(2002)088[0003:pasasa]2.0.co;2] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Philip T LoVerde
- Department of Microbiology, School of Medicine and Biomedical Sciences, State University of New York, Buffalo 14214, USA.
| |
Collapse
|
25
|
Hoffmann KF, Johnston DA, Dunne DW. Identification of Schistosoma mansoni gender-associated gene transcripts by cDNA microarray profiling. Genome Biol 2002; 3:RESEARCH0041. [PMID: 12186648 PMCID: PMC126235 DOI: 10.1186/gb-2002-3-8-research0041] [Citation(s) in RCA: 46] [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: 04/23/2002] [Revised: 05/24/2002] [Accepted: 06/11/2002] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Parasitic helminths of the genus Schistosoma mate, achieve sexual maturity and produce eggs in the bloodstream of their definitive hosts, and the most important pathological consequences of the infection are associated with this process. We have used cDNA microarray technology to initiate genome-wide gene-expression studies of sex and sexual development in mature Schistosoma mansoni parasites. RESULTS An S. mansoni-specific cDNA microarray was fabricated using 576 expressed sequence tags selected from three cDNA libraries and originating from two different parasite developmental stages. Five independent cDNA microarray hybridizations were analyzed using stringent filtering criteria and careful quality control, leading to the identification of 12 new female-associated and 4 new male-associated gene transcripts in the mature adult schistosome. Statistical analysis of variation demonstrated high levels of agreement within a cDNA microarray (correlation coefficient 0.91; median coefficient of variation 11.1%) and between cDNA microarrays (correlation coefficient 0.90; median coefficient of variation 14.4%). RT-PCR analysis confirmed the cDNA microarray results, thereby supporting the reliability of the system. CONCLUSIONS Our study expands the list of S. mansoni gender-associated gene transcripts from all previous studies by a factor of two. Among the new associations identified, a tyrosinase ortholog was preferentially expressed in the adult female, and a dynein light-chain ortholog was highly induced in the adult male. cDNA microarrays offer the potential for exponential leaps in the understanding of parasite biology and this study shows how molecules involved in sexual biology can be rapidly identified.
Collapse
Affiliation(s)
- Karl F Hoffmann
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK.
| | | | | |
Collapse
|
26
|
Abstract
Schistosoma mansoni genomic DNA from male and female adult worms was subjected to restriction by the isoschizomeric endonucleases HpaII and MspI, which display different sensitivities with respect to cytosine methylation. The digested DNA was hybridized with 13 S. mansoni probes. Southern blot analysis showed that there were no observable differences in the restriction patterns of the two isoschizomers and that the patterns were identical in male and female parasites. Adenine methylation was also ruled out since no differences were observed with DpnI, Sau3A1, or MboI restriction enzymes. The methylation-dependent restriction endonuclease McrBC, which cleaves DNA containing methylcytosine and will not cleave unmethylated DNA, did not digest S. mansoni genomic DNA. These results demonstrate that the genome of adult S. mansoni is not methylated.
Collapse
Affiliation(s)
- M R Fantappié
- Departamento de Bioquímica Médica ICB/CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundão CEP 21941-590, Rio de Janeiro, Brazil
| | | | | |
Collapse
|
27
|
Osman A, Niles EG, LoVerde PT. Identification and characterization of a Smad2 homologue from Schistosoma mansoni, a transforming growth factor-beta signal transducer. J Biol Chem 2001; 276:10072-82. [PMID: 11152451 DOI: 10.1074/jbc.m005933200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Smad proteins are essential intracellular signal transducers of the transforming growth factor-beta (TGF-beta) superfamily. The TGF-beta superfamily signals through phosphorylation and activation of R-Smad proteins, receptor-regulated Smads, by heteromeric complexes of ligand-specific type I and type II serine/threonine kinase receptors. R-Smads receive a signal from the activated receptor complex and transmit it to the nucleus. A cDNA was isolated that encodes a 649-amino acid protein found to be homologous to members of R-Smad subfamily with highest homology scored to clawed African frog and human Smad2. The Schistosoma mansoni homologue (SmSmad2) was overexpressed in bacteria as a Sj26-GST fusion protein and used to raise specific antibodies. The IgG fraction of the immunized rabbit serum identified 70- and 72-kDa protein bands in Western analysis of schistosome extracts. Treatment with alkaline phosphatase removed the 72-kDa band, which indicates that this band represents the phosphorylated form of schistosome Smad2. SmSmad2 was localized in the subtegument, parenchymal cells, and sex organs in both male and female worm cryosections. Similar results were also obtained from the analysis of the Smad2 mRNA distribution pattern revealed by in situ hybridization of adult worm pair paraffin sections. SmSmad2 mRNA levels were determined by reverse transcriptase-polymerase chain reaction in different mammalian host developmental stages and found to be constitutively expressed. SmSmad2 was also found to interact with a previously identified SmTbetaR-I, a serine/threonine type I kinase receptor. Furthermore, SmSmad2 was shown to undergo phosphorylation by constitutively active forms of SmTbetaR-I in vitro. In addition, SmSmad2 localized in the nuclei of mink lung epithelial cells upon treatment with TGF-beta(1). These data indicate that the SmSmad2 responds to the TGF-beta signals by interaction with receptor I, which phosphorylates it, whereupon it translocates into the nucleus presumably to regulate target gene transcription and consequently elicit a specific TGF-beta effect.
Collapse
Affiliation(s)
- A Osman
- Department of Microbiology and Center for Microbial Pathogenesis, School of Medicine and Biomedical Sciences, State University of New York, Buffalo 14214, USA
| | | | | |
Collapse
|
28
|
Hoffmann KF, Davis EM, Fischer ER, Wynn TA. The guanine protein coupled receptor rhodopsin is developmentally regulated in the free-living stages of Schistosoma mansoni. Mol Biochem Parasitol 2001; 112:113-23. [PMID: 11166392 DOI: 10.1016/s0166-6851(00)00352-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Schistosoma mansoni parasites inhabit three distinct environments including water, intermediate molluscan hosts, and definitive vertebrate hosts. Determining how schistosomes interact with these environments may be one mechanism by which suitable vaccines or novel chemotherapeutic targets will be identified. Towards this end, we describe the identification of a 36-kDa S. mansoni protein that shares extensive sequence similarity to light absorbing rhodopsin guanine protein coupled receptors (GPCRs). This protein, S. mansoni rhodopsin (SmRHO), is the first molecularly characterized GPCR described in schistosomes. Sequence analysis reveals that SmRHO shares extensive phylogenetic conservation among rhodopsins/opsins expressed in water-dwelling invertebrates, possibly indicative of orthology. We demonstrate here that SmRHO is expressed in the free-living, light responsive miracidia and cercaria stages and is down-regulated in the adult, vertebrate residing forms. Moreover, we show that SmRHO is localized to sub-tegumental structures found towards the anterior end of cercariae. As SmRHO may be implicated in schistosome photoreception processes, we have begun a search for additional parasite encoded GPCR super-family members, which may be associated with chemoreception, chemotaxis, and olfaction. Identifying and characterizing new GPCRs may uncover hidden aspects of parasite biology useful towards the development of novel intervention strategies.
Collapse
Affiliation(s)
- K F Hoffmann
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike Bldg. 7/Room 318, Bethesda, MD 20892, USA.
| | | | | | | |
Collapse
|
29
|
Valle C, Festucci A, Calogero A, Macrì P, Mecozzi B, Liberti P, Cioli D. Stage-specific expression of a Schistosoma mansoni polypeptide similar to the vertebrate regulatory protein stathmin. J Biol Chem 1999; 274:33869-74. [PMID: 10567347 DOI: 10.1074/jbc.274.48.33869] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ubiquitous vertebrate protein stathmin is expressed and phosphorylated in response to a variety of external and internal signals. Stathmin, in turn, controls cell growth and differentiation through its capacity to regulate microtubule assembly dynamics. This is the first report on the molecular cloning and characterization of a stathmin-like protein (SmSLP) in an invertebrate, the human blood fluke Schistosoma mansoni. SmSLP is first synthesized at high levels in the intermediate molluscan host and completely disappears 48 h after penetration into the mammalian host. The protein is preferentially iodinated in intact immature parasites using the Bolton-Hunter reagent, can be quantitatively extracted in high salt buffers, and remains soluble after boiling. Native SmSLP was partially sequenced, and its complete structure was derived from the cloning and sequencing of its cDNA. The sequence is up to 26% identical to vertebrate stathmin sequences and contains two potential phosphorylation sites. Native SmSLP is indeed phosphorylated because phosphatase digestion shifts its mobility in electrofocusing gels. SmSLP associates with tubulin, as suggested by immune co-precipitation results. In vitro experiments demonstrated that SmSLP inhibits tubulin assembly and causes the depolymerization of preassembled microtubules, thus probably fulfilling regulatory roles in critical steps of schistosome development.
Collapse
Affiliation(s)
- C Valle
- Institute of Cell Biology, National Research Council, 43 Viale Marx, 00137 Rome, Italy
| | | | | | | | | | | | | |
Collapse
|