1
|
Derkaczew M, Martyniuk P, Hofman R, Rutkowski K, Osowski A, Wojtkiewicz J. The Genetic Background of Abnormalities in Metabolic Pathways of Phosphoinositides and Their Linkage with the Myotubular Myopathies, Neurodegenerative Disorders, and Carcinogenesis. Biomolecules 2023; 13:1550. [PMID: 37892232 PMCID: PMC10605126 DOI: 10.3390/biom13101550] [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: 08/27/2023] [Revised: 09/16/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Myo-inositol belongs to one of the sugar alcohol groups known as cyclitols. Phosphatidylinositols are one of the derivatives of Myo-inositol, and constitute important mediators in many intracellular processes such as cell growth, cell differentiation, receptor recycling, cytoskeletal organization, and membrane fusion. They also have even more functions that are essential for cell survival. Mutations in genes encoding phosphatidylinositols and their derivatives can lead to many disorders. This review aims to perform an in-depth analysis of these connections. Many authors emphasize the significant influence of phosphatidylinositols and phosphatidylinositols' phosphates in the pathogenesis of myotubular myopathies, neurodegenerative disorders, carcinogenesis, and other less frequently observed diseases. In our review, we have focused on three of the most often mentioned groups of disorders. Inositols are the topic of many studies, and yet, there are no clear results of successful clinical trials. Analysis of the available literature gives promising results and shows that further research is still needed.
Collapse
Affiliation(s)
- Maria Derkaczew
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Piotr Martyniuk
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Robert Hofman
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Krzysztof Rutkowski
- Students’ Scientific Club of Pathophysiologists, Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- The Nicolaus Copernicus Municipal Polyclinical Hospital in Olsztyn, 10-045 Olsztyn, Poland
| | - Adam Osowski
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| | - Joanna Wojtkiewicz
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, 10-082 Olsztyn, Poland
| |
Collapse
|
2
|
Alves E, Nakaya H, Guimarães E, Garcia CR. Combining IP 3 affinity chromatography and bioinformatics reveals a novel protein-IP 3 binding site on Plasmodium falciparum MDR1 transporter. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 4:100179. [PMID: 36582189 PMCID: PMC9792294 DOI: 10.1016/j.crmicr.2022.100179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Intracellular Ca2+ mobilization induced by second messenger IP3 controls many cellular events in most of the eukaryotic groups. Despite the increasing evidence of IP3-induced Ca2+ in apicomplexan parasites like Plasmodium, responsible for malaria infection, no protein with potential function as an IP3-receptor has been identified. The use of bioinformatic analyses based on previously known sequences of IP3-receptor failed to identify potential IP3-receptor candidates in any Apicomplexa. In this work, we combine the biochemical approach of an IP3 affinity chromatography column with bioinformatic meta-analyses to identify potential vital membrane proteins that present binding with IP3 in Plasmodium falciparum. Our analyses reveal that PF3D7_0523000, a gene that codes a transport protein associated with multidrug resistance as a potential target for IP3. This work provides a new insight for probing potential candidates for IP3-receptor in Apicomplexa.
Collapse
Affiliation(s)
- Eduardo Alves
- Life Science Department, Imperial College London, London, United Kingdom
| | - Helder Nakaya
- Department of Clinical and Toxicological Analyses of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil,Computational Systems Biology Laboratory, INOVA, University of Sao Paulo, Sao Paulo, Brazil
| | - Euzébio Guimarães
- Federal University of Rio Grande do Norte, Pharmacy Department, Health Science Center, Natal, Brazil
| | - Célia R.S. Garcia
- Department of Clinical and Toxicological Analyses of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil,Corresponding author.
| |
Collapse
|
3
|
A Phosphoinositide-Binding Protein Acts in the Trafficking Pathway of Hemoglobin in the Malaria Parasite Plasmodium falciparum. mBio 2022; 13:e0323921. [PMID: 35038916 PMCID: PMC8764524 DOI: 10.1128/mbio.03239-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Phosphoinositide lipids play key roles in a variety of processes in eukaryotic cells, but our understanding of their functions in the malaria parasite Plasmodium falciparum is still very much limited. To gain a deeper comprehension of the roles of phosphoinositides in this important pathogen, we attempted gene inactivation for 24 putative effectors of phosphoinositide metabolism. Our results reveal that 79% of the candidates are refractory to genetic deletion and are therefore potentially essential for parasite growth. Inactivation of the gene coding for a Plasmodium-specific putative phosphoinositide-binding protein, which we named PfPX1, results in a severe growth defect. We show that PfPX1 likely binds phosphatidylinositol-3-phosphate and that it localizes to the membrane of the digestive vacuole of the parasite and to vesicles filled with host cell cytosol and labeled with endocytic markers. Critically, we provide evidence that it is important in the trafficking pathway of hemoglobin from the host erythrocyte to the digestive vacuole. Finally, inactivation of PfPX1 renders parasites resistant to artemisinin, the frontline antimalarial drug. Globally, the minimal redundancy in the putative phosphoinositide proteins uncovered in our work supports that targeting this pathway has potential for antimalarial drug development. Moreover, our identification of a phosphoinositide-binding protein critical for the trafficking of hemoglobin provides key insight into this essential process. IMPORTANCE Malaria represents an enormous burden for a significant proportion of humanity, and the lack of vaccines and problems with drug resistance to all antimalarials demonstrate the need to develop new therapeutics. Inhibitors of phosphoinositide metabolism are currently being developed as antimalarials but our understanding of this biological pathway is incomplete. The malaria parasite lives inside human red blood cells where it imports hemoglobin to cover some of its nutritional needs. In this work, we have identified a phosphoinositide-binding protein that is important for the transport of hemoglobin in the parasite. Inactivation of this protein decreases the ability of the parasite to proliferate. Our results have therefore identified a potential new target for antimalarial development.
Collapse
|
4
|
Ren B, Kong P, Hedar F, Brouwers JF, Gupta N. Phosphatidylinositol synthesis, its selective salvage, and inter-regulation of anionic phospholipids in Toxoplasma gondii. Commun Biol 2020; 3:750. [PMID: 33303967 PMCID: PMC7728818 DOI: 10.1038/s42003-020-01480-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 11/11/2020] [Indexed: 02/07/2023] Open
Abstract
Phosphatidylinositol (PtdIns) serves as an integral component of eukaryotic membranes; however, its biosynthesis in apicomplexan parasites remains poorly understood. Here we show that Toxoplasma gondii-a common intracellular pathogen of humans and animals-can import and co-utilize myo-inositol with the endogenous CDP-diacylglycerol to synthesize PtdIns. Equally, the parasite harbors a functional PtdIns synthase (PIS) containing a catalytically-vital CDP-diacylglycerol phosphotransferase motif in the Golgi apparatus. Auxin-induced depletion of PIS abrogated the lytic cycle of T. gondii in human cells due to defects in cell division, gliding motility, invasion, and egress. Isotope labeling of the PIS mutant in conjunction with lipidomics demonstrated de novo synthesis of specific PtdIns species, while revealing the salvage of other lipid species from the host cell. Not least, the mutant showed decline in phosphatidylthreonine, and elevation of selected phosphatidylserine and phosphatidylglycerol species, indicating a rerouting of CDP-diacylglycerol and homeostatic inter-regulation of anionic phospholipids upon knockdown of PIS. In conclusion, strategic allocation of own and host-derived PtdIns species to gratify its metabolic demand features as a notable adaptive trait of T. gondii. Conceivably, the dependence of T. gondii on de novo lipid synthesis and scavenging can be exploited to develop new anti-infectives.
Collapse
Affiliation(s)
- Bingjian Ren
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Pengfei Kong
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Fatima Hedar
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Jos F Brouwers
- Center for Molecular Medicine, University Medical Center, Utrecht, The Netherlands
| | - Nishith Gupta
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany.
- Department of Biological Sciences, Birla Institute of Technology and Science Pilani (BITS-P), Hyderabad, India.
| |
Collapse
|
5
|
Aguiar AC, de Sousa LR, Garcia CR, Oliva G, Guido RV. New Molecular Targets and Strategies for Antimalarial Discovery. Curr Med Chem 2019; 26:4380-4402. [DOI: 10.2174/0929867324666170830103003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/24/2017] [Accepted: 07/24/2017] [Indexed: 02/07/2023]
Abstract
Malaria remains a major health problem, especially because of the emergence
of resistant P. falciparum strains to artemisinin derivatives. In this context, safe and affordable
antimalarial drugs are desperately needed. New proteins have been investigated
as molecular targets for research and development of innovative compounds with welldefined
mechanism of action. In this review, we highlight genetically and clinically validated
plasmodial proteins as drug targets for the next generation of therapeutics. The enzymes
described herein are involved in hemoglobin hydrolysis, the invasion process,
elongation factors for protein synthesis, pyrimidine biosynthesis, post-translational modifications
such as prenylation, phosphorylation and histone acetylation, generation of ATP
in mitochondrial metabolism and aminoacylation of RNAs. Significant advances on proteomics,
genetics, structural biology, computational and biophysical methods provided
invaluable molecular and structural information about these drug targets. Based on this,
several strategies and models have been applied to identify and improve lead compounds.
This review presents the recent progresses in the discovery of antimalarial drug candidates,
highlighting the approaches, challenges, and perspectives to deliver affordable, safe
and low single-dose medicines to treat malaria.
Collapse
Affiliation(s)
- Anna Caroline Aguiar
- Sao Carlos Institute of Physics, University of Sao Paulo, PO Box 369, 13560-970, Sao Carlos, SP, Brazil
| | - Lorena R.F. de Sousa
- Sao Carlos Institute of Physics, University of Sao Paulo, PO Box 369, 13560-970, Sao Carlos, SP, Brazil
| | - Celia R.S. Garcia
- Physiology Department, Bioscience Institute, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Glaucius Oliva
- Sao Carlos Institute of Physics, University of Sao Paulo, PO Box 369, 13560-970, Sao Carlos, SP, Brazil
| | - Rafael V.C. Guido
- Sao Carlos Institute of Physics, University of Sao Paulo, PO Box 369, 13560-970, Sao Carlos, SP, Brazil
| |
Collapse
|
6
|
Wengelnik K, Daher W, Lebrun M. Phosphoinositides and their functions in apicomplexan parasites. Int J Parasitol 2018; 48:493-504. [PMID: 29596862 DOI: 10.1016/j.ijpara.2018.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 01/26/2018] [Accepted: 01/29/2018] [Indexed: 11/28/2022]
Abstract
Phosphoinositides are the phosphorylated derivatives of the structural membrane phospholipid phosphatidylinositol. Single or combined phosphorylation at the 3, 4 and 5 positions of the inositol ring gives rise to the seven different species of phosphoinositides. All are quantitatively minor components of cellular membranes but have been shown to have important functions in multiple cellular processes. Here we describe our current knowledge of phosphoinositide metabolism and functions in apicomplexan parasites, mainly focusing on Toxoplasma gondii and Plasmodium spp. Even though our understanding is still rudimentary, phosphoinositides have already shown their importance in parasite biology and revealed some very particular and parasite-specific functions. Not surprisingly, there is a strong potential for phosphoinositide synthesis to be exploited for future anti-parasitic drug development.
Collapse
Affiliation(s)
- Kai Wengelnik
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France.
| | - Wassim Daher
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France
| | - Maryse Lebrun
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR5235 CNRS, INSERM, Université Montpellier, Montpellier, France.
| |
Collapse
|
7
|
Ebrahimzadeh Z, Mukherjee A, Richard D. A map of the subcellular distribution of phosphoinositides in the erythrocytic cycle of the malaria parasite Plasmodium falciparum. Int J Parasitol 2017; 48:13-25. [PMID: 29154995 DOI: 10.1016/j.ijpara.2017.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 08/22/2017] [Accepted: 08/31/2017] [Indexed: 12/16/2022]
Abstract
Despite representing a small percentage of the cellular lipids of eukaryotic cells, phosphoinositides (PIPs) are critical in various processes such as intracellular trafficking and signal transduction. Central to their various functions is the differential distribution of PIP species to specific membrane compartments through the actions of kinases, phosphatases and lipases. Despite their importance in the malaria parasite lifecycle, the subcellular distribution of most PIP species in this organism is still unknown. We here localise several species of PIPs throughout the erythrocytic cycle of Plasmodium falciparum. We show that PI3P is mostly found at the apicoplast and the membrane of the food vacuole, that PI4P associates with the Golgi apparatus and the plasma membrane and that PI(4,5)P2, in addition to being detected at the plasma membrane, labels some cavity-like spherical structures. Finally, we show that the elusive PI5P localises to the plasma membrane, the nucleus and potentially to the transitional endoplasmic reticulum (ER). Our map of the subcellular distribution of PIP species in P. falciparum will be a useful tool to shed light on the dynamics of these lipids in this deadly parasite.
Collapse
Affiliation(s)
- Zeinab Ebrahimzadeh
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Angana Mukherjee
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Dave Richard
- Centre de recherche en infectiologie, CRCHU de Québec-Université Laval, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada.
| |
Collapse
|
8
|
Garcia CRS, Alves E, Pereira PHS, Bartlett PJ, Thomas AP, Mikoshiba K, Plattner H, Sibley LD. InsP3 Signaling in Apicomplexan Parasites. Curr Top Med Chem 2017; 17:2158-2165. [PMID: 28137231 PMCID: PMC5490149 DOI: 10.2174/1568026617666170130121042] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/20/2016] [Accepted: 10/30/2016] [Indexed: 11/22/2022]
Abstract
Background:
Phosphoinositides (PIs) and their derivatives are essential cellular components that form the building blocks for cell membranes and regulate numerous cell functions. Specifically, the ability to generate myo-inositol 1,4,5-trisphosphate (InsP3) via phospholipase C (PLC) dependent hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) to InsP3 and diacylglycerol (DAG) initiates intracellular calcium signaling events representing a fundamental signaling mechanism dependent on PIs. InsP3 produced by PI turnover as a second messenger causes intracellular calcium release, especially from endoplasmic reticulum, by binding to the InsP3 receptor (InsP3R). Various PIs and the enzymes, such as phosphatidylinositol synthase and phosphatidylinositol 4-kinase, necessary for their turnover have been characterized in Apicomplexa, a large phylum of mostly commensal organisms that also includes several clinically relevant parasites. However, InsP3Rs have not been identified in genomes of apicomplexans, despite evidence that these parasites produce InsP3 that mediates intracellular Ca2+ signaling. Conclusion: Evidence to supporting IP3-dependent signaling cascades in apicomplexans suggests that they may harbor a primitive or non-canonical InsP3R. Understanding these pathways may be informative about early branching eukaryotes, where such signaling pathways also diverge from animal systems, thus identifying potential novel and essential targets for therapeutic intervention.
Collapse
Affiliation(s)
- Celia R S Garcia
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo. Sao Paulo 05508-090, Brazil
| | - Eduardo Alves
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo. Sao Paulo 05508-000, Brazil
| | - Pedro H S Pereira
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo. Sao Paulo 05508-090, Brazil,Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo. Sao Paulo 05508-000, Brazil
| | - Paula J Bartlett
- New Jersey Medical School, Rutgers, The State University of New Jersey, New Jersey, USA
| | - Andrew P Thomas
- New Jersey Medical School, Rutgers, The State University of New Jersey, New Jersey, USA
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Helmut Plattner
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - L David Sibley
- Department of Molecular Microbiology, Washington University Sch. Med., Saint Louis, USA
| |
Collapse
|
9
|
Macrae JI, Lopaticki S, Maier AG, Rupasinghe T, Nahid A, Cowman AF, McConville MJ. Plasmodium falciparum is dependent on de novo myo-inositol biosynthesis for assembly of GPI glycolipids and infectivity. Mol Microbiol 2014; 91:762-76. [PMID: 24350823 DOI: 10.1111/mmi.12496] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2013] [Indexed: 12/27/2022]
Abstract
Intra-erythrocytic stages of the malaria parasite, Plasmodium falciparum, are thought to be dependent on de novo synthesis of phosphatidylinositol, as red blood cells (RBC) lack the capacity to synthesize this phospholipid. The myo-inositol headgroup of PI can either be synthesized de novo or scavenged from the RBC. An untargeted metabolite profiling of P. falciparum infected RBC showed that trophozoite and schizont stages accumulate high levels of myo-inositol-3-phosphate, indicating increased de novo biosynthesis of myo-inositol from glucose 6-phosphate. Metabolic labelling studies with (13) C-U-glucose in the presence and absence of exogenous inositol confirmed that de novo myo-inositol synthesis occurs in parallel with myo-inositol salvage pathways. Unexpectedly, while both endogenous and scavenged myo-inositol was used to synthesize bulk PI, only de novo-synthesized myo-inositol was incorporated into GPI glycolipids. Moreover, gene disruption studies suggested that the INO1 gene, encoding myo-inositol 3-phosphate synthase, is essential in asexual parasite stages. Together these findings suggest that P. falciparum asexual stages are critically dependent on de novo myo-inositol biosynthesis for assembly of a sub-pool of PI species and GPI biosynthesis. These findings highlight unexpected complexity in phospholipid biosynthesis in P. falciparum and a lack of redundancy in some nutrient salvage versus endogenous biosynthesis pathways.
Collapse
Affiliation(s)
- James I Macrae
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, 30 Flemington Road, Melbourne, Vic., 3010, Australia
| | | | | | | | | | | | | |
Collapse
|
10
|
Abstract
Phosphoinositides (PIs) make up only a small fraction of cellular phospholipids, yet they control almost all aspects of a cell's life and death. These lipids gained tremendous research interest as plasma membrane signaling molecules when discovered in the 1970s and 1980s. Research in the last 15 years has added a wide range of biological processes regulated by PIs, turning these lipids into one of the most universal signaling entities in eukaryotic cells. PIs control organelle biology by regulating vesicular trafficking, but they also modulate lipid distribution and metabolism via their close relationship with lipid transfer proteins. PIs regulate ion channels, pumps, and transporters and control both endocytic and exocytic processes. The nuclear phosphoinositides have grown from being an epiphenomenon to a research area of its own. As expected from such pleiotropic regulators, derangements of phosphoinositide metabolism are responsible for a number of human diseases ranging from rare genetic disorders to the most common ones such as cancer, obesity, and diabetes. Moreover, it is increasingly evident that a number of infectious agents hijack the PI regulatory systems of host cells for their intracellular movements, replication, and assembly. As a result, PI converting enzymes began to be noticed by pharmaceutical companies as potential therapeutic targets. This review is an attempt to give an overview of this enormous research field focusing on major developments in diverse areas of basic science linked to cellular physiology and disease.
Collapse
Affiliation(s)
- Tamas Balla
- Section on Molecular Signal Transduction, Program for Developmental Neuroscience, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
| |
Collapse
|
11
|
Lipid synthesis in protozoan parasites: a comparison between kinetoplastids and apicomplexans. Prog Lipid Res 2013; 52:488-512. [PMID: 23827884 DOI: 10.1016/j.plipres.2013.06.003] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 06/16/2013] [Accepted: 06/17/2013] [Indexed: 12/22/2022]
Abstract
Lipid metabolism is of crucial importance for pathogens. Lipids serve as cellular building blocks, signalling molecules, energy stores, posttranslational modifiers, and pathogenesis factors. Parasites rely on a complex system of uptake and synthesis mechanisms to satisfy their lipid needs. The parameters of this system change dramatically as the parasite transits through the various stages of its life cycle. Here we discuss the tremendous recent advances that have been made in the understanding of the synthesis and uptake pathways for fatty acids and phospholipids in apicomplexan and kinetoplastid parasites, including Plasmodium, Toxoplasma, Cryptosporidium, Trypanosoma and Leishmania. Lipid synthesis differs in significant ways between parasites from both phyla and the human host. Parasites have acquired novel pathways through endosymbiosis, as in the case of the apicoplast, have dramatically reshaped substrate and product profiles, and have evolved specialized lipids to interact with or manipulate the host. These differences potentially provide opportunities for drug development. We outline the lipid pathways for key species in detail as they progress through the developmental cycle and highlight those that are of particular importance to the biology of the pathogens and/or are the most promising targets for parasite-specific treatment.
Collapse
|
12
|
Deponte M, Hoppe HC, Lee MC, Maier AG, Richard D, Rug M, Spielmann T, Przyborski JM. Wherever I may roam: Protein and membrane trafficking in P. falciparum-infected red blood cells. Mol Biochem Parasitol 2012; 186:95-116. [DOI: 10.1016/j.molbiopara.2012.09.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 11/27/2022]
|
13
|
Payrastre B, Gaits-Iacovoni F, Sansonetti P, Tronchère H. Phosphoinositides and cellular pathogens. Subcell Biochem 2012; 59:363-388. [PMID: 22374097 DOI: 10.1007/978-94-007-3015-1_12] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Phosphoinositides are considered as highly dynamic players in the spatiotemporal organization of key signaling pathways, actin cytoskeleton rearrangements, establishment of cell polarity and intracellular vesicle trafficking. Their metabolism is accurately controlled and mutations in several phosphoinositide metabolizing enzymes take part in the development of human pathologies. Interestingly, evidence is accumulating that modulation of the phosphoinositide metabolism is critical for pathogenicity and virulence of many human pathogens. Given the importance of phosphoinositides, which link membrane and cytoskeleton dynamics to cell responses, it is not surprising that many invasive pathogens hijack their metabolism as part of their strategies to establish infection. In fact, according to their lifestyle, cellular pathogens use the phosphoinositide metabolism in order to trigger their uptake in nonphagocytic cells and/or modulate the maturation of the pathogen-containing vacuole to establish their replicative niche or escape in the cytosol and promote host cell survival. The last two decades have been marked by the discovery of different tactics used by cellular pathogens to modulate the phosphoinositide metabolism as part of their strategies to survive, proliferate and disseminate in a hostile environment.
Collapse
Affiliation(s)
- Bernard Payrastre
- Inserm, U1048, Université Toulouse 3, I2MC, Hôpital de Toulouse, BP 84225 Avenue Jean Poulhès, 31432, Toulouse Cedex 04, France,
| | | | | | | |
Collapse
|
14
|
Raabe A, Berry L, Sollelis L, Cerdan R, Tawk L, Vial HJ, Billker O, Wengelnik K. Genetic and transcriptional analysis of phosphoinositide-specific phospholipase C in Plasmodium. Exp Parasitol 2011; 129:75-80. [DOI: 10.1016/j.exppara.2011.05.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 05/05/2011] [Accepted: 05/24/2011] [Indexed: 12/01/2022]
|
15
|
Raabe AC, Wengelnik K, Billker O, Vial HJ. Multiple roles for Plasmodium berghei phosphoinositide-specific phospholipase C in regulating gametocyte activation and differentiation. Cell Microbiol 2011; 13:955-66. [PMID: 21518218 PMCID: PMC3132445 DOI: 10.1111/j.1462-5822.2011.01591.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Critical events in the life cycle of malaria parasites are controlled by calcium-dependent signalling cascades, yet the molecular mechanisms of calcium release remain poorly understood. The synchronized development of Plasmodium berghei gametocytes relies on rapid calcium release from internal stores within 10 s of gametocytes being exposed to mosquito-derived xanthurenic acid (XA). Here we addressed the function of phosphoinositide-specific phospholipase C (PI-PLC) for regulating gametocyte activation. XA triggered the hydrolysis of PIP2 and the production of the secondary messenger IP3 in gametocytes. Both processes were selectively blocked by a PI-PLC inhibitor, which also reduced the early Ca2+ signal. However, microgametocyte differentiation into microgametes was blocked even when the inhibitor was added up to 5 min after activation, suggesting a requirement for PI-PLC beyond the early mobilization of calcium. In contrast, inhibitors of calcium release through ryanodine receptor channels were active only during the first minute of gametocyte activation. Biochemical determination of PI-PLC activity was confirmed using transgenic parasites expressing a fluorescent PIP2/IP3 probe that translocates from the parasite plasmalemma to the cytosol upon cell activation. Our study revealed a complex interdependency of Ca2+ and PI-PLC activity, with PI-PLC being essential throughout gamete formation, possibly explaining the irreversibility of this process.
Collapse
Affiliation(s)
- Andreas C Raabe
- UMR5235, CNRS-Université Montpellier 2, Place Eugène Bataillon, Montpellier cedex 5, France
| | | | | | | |
Collapse
|
16
|
Alves E, Bartlett PJ, Garcia CRS, Thomas AP. Melatonin and IP3-induced Ca2+ release from intracellular stores in the malaria parasite Plasmodium falciparum within infected red blood cells. J Biol Chem 2010; 286:5905-12. [PMID: 21149448 DOI: 10.1074/jbc.m110.188474] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
IP(3)-dependent Ca(2+) signaling controls a myriad of cellular processes in higher eukaryotes and similar signaling pathways are evolutionarily conserved in Plasmodium, the intracellular parasite that causes malaria. We have reported that isolated, permeabilized Plasmodium chabaudi, releases Ca(2+) upon addition of exogenous IP(3). In the present study, we investigated whether the IP(3) signaling pathway operates in intact Plasmodium falciparum, the major disease-causing human malaria parasite. P. falciparum-infected red blood cells (RBCs) in the trophozoite stage were simultaneously loaded with the Ca(2+) indicator Fluo-4/AM and caged-IP(3). Photolytic release of IP(3) elicited a transient Ca(2+) increase in the cytosol of the intact parasite within the RBC. The intracellular Ca(2+) pools of the parasite were selectively discharged, using thapsigargin to deplete endoplasmic reticulum (ER) Ca(2+) and the antimalarial chloroquine to deplete Ca(2+) from acidocalcisomes. These data show that the ER is the major IP(3)-sensitive Ca(2+) store. Previous work has shown that the human host hormone melatonin regulates P. falciparum cell cycle via a Ca(2+)-dependent pathway. In the present study, we demonstrate that melatonin increases inositol-polyphosphate production in intact intraerythrocytic parasite. Moreover, the Ca(2+) responses to melatonin and uncaging of IP(3) were mutually exclusive in infected RBCs. Taken together these data provide evidence that melatonin activates PLC to generate IP(3) and open ER-localized IP(3)-sensitive Ca(2+) channels in P. falciparum. This receptor signaling pathway is likely to be involved in the regulation and synchronization of parasite cell cycle progression.
Collapse
Affiliation(s)
- Eduardo Alves
- Department of Pharmacology and Physiology, UMDNJ, New Jersey Medical School, Newark, New Jersey 07103, USA
| | | | | | | |
Collapse
|
17
|
Phosphatidylinositol 3-phosphate, an essential lipid in Plasmodium, localizes to the food vacuole membrane and the apicoplast. EUKARYOTIC CELL 2010; 9:1519-30. [PMID: 20709789 DOI: 10.1128/ec.00124-10] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phosphoinositides are important regulators of diverse cellular functions, and phosphatidylinositol 3-monophosphate (PI3P) is a key element in vesicular trafficking processes. During its intraerythrocytic development, the malaria parasite Plasmodium falciparum establishes a sophisticated but poorly characterized protein and lipid trafficking system. Here we established the detailed phosphoinositide profile of P. falciparum-infected erythrocytes and found abundant amounts of PI3P, while phosphatidylinositol 3,5-bisphosphate was not detected. PI3P production was parasite dependent, sensitive to a phosphatidylinositol-3-kinase (PI3-kinase) inhibitor, and predominant in late parasite stages. The Plasmodium genome encodes a class III PI3-kinase of unusual size, containing large insertions and several repetitive sequence motifs. The gene could not be deleted in Plasmodium berghei, and in vitro growth of P. falciparum was sensitive to a PI3-kinase inhibitor, indicating that PI3-kinase is essential in Plasmodium blood stages. For intraparasitic PI3P localization, transgenic P. falciparum that expressed a PI3P-specific fluorescent probe was generated. Fluorescence was associated mainly with the membrane of the food vacuole and with the apicoplast, a four-membrane bounded plastid-like organelle derived from an ancestral secondary endosymbiosis event. Electron microscopy analysis confirmed these findings and revealed, in addition, the presence of PI3P-positive single-membrane vesicles. We hypothesize that these vesicles might be involved in transport processes, likely of proteins and lipids, toward the essential and peculiar parasite compartment, which is the apicoplast. The fact that PI3P metabolism and function in Plasmodium appear to be substantially different from those in its human host could offer new possibilities for antimalarial chemotherapy.
Collapse
|
18
|
Krüger T, Sanchez CP, Lanzer M. Complementation of Saccharomyces cerevisiae pik1ts by a phosphatidylinositol 4-kinase from Plasmodium falciparum. Mol Biochem Parasitol 2010; 172:149-51. [DOI: 10.1016/j.molbiopara.2010.03.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/26/2010] [Accepted: 03/31/2010] [Indexed: 11/25/2022]
|
19
|
Déchamps S, Shastri S, Wengelnik K, Vial HJ. Glycerophospholipid acquisition in Plasmodium - a puzzling assembly of biosynthetic pathways. Int J Parasitol 2010; 40:1347-65. [PMID: 20600072 DOI: 10.1016/j.ijpara.2010.05.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 05/24/2010] [Accepted: 05/25/2010] [Indexed: 01/06/2023]
Abstract
Throughout the Plasmodium life cycle, malaria parasites repeatedly undergo rapid cellular growth and prolific divisions, necessitating intense membrane neogenesis and, in particular, the acquisition of high amounts of phospholipids. At the intraerythrocytic stage, glycerophospholipids are the main parasite membrane constituents, which mostly originate from the Plasmodium-encoded enzymatic machinery. Several proteins and entire pathways have been characterized and their features reported, thereby generating a global view of glycerophospholipid synthesis across Plasmodium spp. The malaria parasite displays a panoply of pathways that are seldom found together in a single organism. The major glycerophospholipids are synthesized via ancestral prokaryotic CDP-diacylglycerol-dependent pathways and eukaryotic-type de novo pathways. The parasite exhibits additional reactions that bridge some of these routes and are otherwise restricted to some organisms, such as plants, while base-exchange mechanisms are largely unexplored in Plasmodium. Marked differences between Plasmodium spp. have also been reported in phosphatidylcholine and phosphatidylethanolamine synthesis. Little is currently known about glycerophospholipid acquisition at non-erythrocytic stages, but recent data reveal that intrahepatocytic parasites, oocysts and sporozoites import various host lipids, and that de novo fatty acid synthesis is only crucial at the late liver stage. More studies on the different Plasmodium developmental stages are needed, to further assemble the different pieces of this glycerophospholipid synthesis puzzle, which contains highly promising therapeutic targets.
Collapse
Affiliation(s)
- Sandrine Déchamps
- Dynamique des Interactions Membranaires Normales et Pathologiques, UMR 5235, Centre National de la Recherche Scientifique (CNRS) - Universite Montpellier 2, cc 107, Place Eugene Bataillon, 34095 Montpellier Cedex 05, France
| | | | | | | |
Collapse
|
20
|
PfPI3K, a phosphatidylinositol-3 kinase from Plasmodium falciparum, is exported to the host erythrocyte and is involved in hemoglobin trafficking. Blood 2010; 115:2500-7. [PMID: 20093402 DOI: 10.1182/blood-2009-08-238972] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Polyphosphorylated phosphoinositides (PIPs) are potent second messengers, which trigger a wide variety of signaling and trafficking events in most eukaryotic cells. However, the role and metabolism of PIPs in malaria parasite Plasmodium have remained largely unexplored. Our present studies suggest that PfPI3K, a novel phosphatidylinositol-3-kinase (PI3K) in Plasmodium falciparum, is exported to the host erythrocyte by the parasite in an active form. PfPI3K is a versatile enzyme as it can generate various 3'-phosphorylated PIPs. In the parasite, PfPI3K was localized in vesicular compartments near the membrane and in its food vacuole. PI3K inhibitors wortmannin and LY294002 were effective against PfPI3K and were used to study PfPI3K function. We found that PfPI3K is involved in endocytosis from the host and trafficking of hemoglobin in the parasite. The inhibition of PfPI3K resulted in entrapment of hemoglobin in vesicles in the parasite cytoplasm, which prevented its transport to the food vacuole, the site of hemoglobin catabolism. As a result, hemoglobin digestion, which is a source of amino acids necessary for parasite growth, was attenuated and caused the inhibition of parasite growth.
Collapse
|
21
|
Beraldo FH, Mikoshiba K, Garcia CRS. Human malarial parasite, Plasmodium falciparum, displays capacitative calcium entry: 2-aminoethyl diphenylborinate blocks the signal transduction pathway of melatonin action on the P. falciparum cell cycle. J Pineal Res 2007; 43:360-4. [PMID: 17910604 DOI: 10.1111/j.1600-079x.2007.00486.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The malarial parasite senses the environment to modulate its own cycle. Knowledge of the mechanisms for regulation signaling processes at the invasion, maturation, as well as division of Plasmodium falciparum before reinvasion would represent a major breakthrough and, therefore, might open new avenues for therapy. We have previously reported that melatonin modulates the circadian rhythm of malarial parasites through the activation of phospholipase C (PLC), production of InsP3, and induction of calcium release from intracellular stores. To further investigate the molecular mechanism of melatonin's action, we have used the InsP3 modulator 2-aminoethyl diphenylborinate (2-APB) given in a culture of P. falciparum parasites. Here we show that the melatonin acts on Plasmodium cell cycle through InsP3 signaling as 2-APB blocks melatonin's effect on calcium release. The function of the InsP3 signaling can be regarded as an important event for parasite invasion and maturation process, since addition of the PLC inhibitor, U73122 into Plasmodium-infected red blood cells impairs parasite invasion in vitro. By using 8BrcAMP, we also report here that Plasmodia displays a 'capacitative calcium entry' mechanism for amplification of calcium signals throughout the cytoplasm.
Collapse
Affiliation(s)
- Flávio H Beraldo
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | | | | |
Collapse
|
22
|
McIntosh MT, Vaid A, Hosgood HD, Vijay J, Bhattacharya A, Sahani MH, Baevova P, Joiner KA, Sharma P. Traffic to the Malaria Parasite Food Vacuole. J Biol Chem 2007; 282:11499-508. [PMID: 17289673 DOI: 10.1074/jbc.m610974200] [Citation(s) in RCA: 32] [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
Phosphatidylinositol 3-phosphate (PI3P) is a key ligand for recruitment of endosomal regulatory proteins in higher eukaryotes. Subsets of these endosomal proteins possess a highly selective PI3P binding zinc finger motif belonging to the FYVE domain family. We have identified a single FYVE domain-containing protein in Plasmodium falciparum which we term FCP. Expression and mutagenesis studies demonstrate that key residues are involved in specific binding to PI3P. In contrast to FYVE proteins in other organisms, endogenous FCP localizes to a lysosomal compartment, the malaria parasite food vacuole (FV), rather than to cytoplasmic endocytic organelles. Transfections of deletion mutants further indicate that FCP is essential for trophozoite and FV maturation and that it traffics to the FV via a novel constitutive cytoplasmic to vacuole targeting pathway. This newly discovered pathway excludes the secretory pathway and is directed by a C-terminal 44-amino acid peptide domain. We conclude that an FYVE protein that might be expected to participate in vesicle targeting in the parasite cytosol instead has a vital and functional role in the malaria parasite FV.
Collapse
Affiliation(s)
- Michael T McIntosh
- Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Wengelnik K, Vial HJ. Characterisation of the phosphatidylinositol synthase gene of Plasmodium species. Res Microbiol 2006; 158:51-9. [PMID: 17223316 DOI: 10.1016/j.resmic.2006.11.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Revised: 11/14/2006] [Accepted: 11/15/2006] [Indexed: 12/21/2022]
Abstract
Phosphatidylinositol (PI) is a versatile lipid that not only serves as a structural component of cellular membranes, but also plays important roles in membrane anchorage of proteins and in signal transduction through distinct phosphorylated derivatives of the inositol head group. PI is synthesised by PI synthase from CDP-diacylglycerol and myo-inositol. The enzymatic activity in Plasmodium falciparum and P. knowlesi has previously been characterised at the biochemical level. Here we characterise the PI synthase gene of P. falciparum and P. knowlesi. The cDNA sequence identified a highly spliced gene consisting of nine exons and encoding a protein of 209 and 207 amino acids, respectively. High sequence conservation enabled the prediction of the PI synthase genes of P. berghei, P. chabaudi and P. vivax. All Plasmodium PI synthase proteins appear to be highly hydrophobic, although no consensus for the number and location of distinct transmembrane domains could be detected. The P. falciparum PI synthase (PfPIS) gene successfully complemented a Saccharomyces cerevisiae PIS1 deletion mutant, demonstrating its enzymatic function. Complementation efficiency was dramatically improved when hybrid constructs between N-terminal S. cerevisiae and C-terminal P. falciparum sequences were used. Determination of in vitro PIS activities of complemented yeast strains confirmed the enzymatic function of the Plasmodium protein.
Collapse
Affiliation(s)
- Kai Wengelnik
- UMR5539, CNRS-Université Montpellier II, Place Eugène Bataillon, cc 107, 34095 Montpellier Cedex 05, France.
| | | |
Collapse
|
24
|
Martin K, Smith T. Phosphatidylinositol synthesis is essential in bloodstream form Trypanosoma brucei. Biochem J 2006; 396:287-95. [PMID: 16475982 PMCID: PMC1462709 DOI: 10.1042/bj20051825] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2005] [Revised: 02/03/2006] [Accepted: 02/14/2006] [Indexed: 12/16/2022]
Abstract
PI (phosphatidylinositol) is a ubiquitous eukaryotic phospholipid which serves as a precursor for messenger molecules and GPI (glycosylphosphatidylinositol) anchors. PI is synthesized either de novo or by head group exchange by a PIS (PI synthase). The synthesis of GPI anchors has previously been validated both genetically and chemically as a drug target in Trypanosoma brucei, the causative parasite of African sleeping sickness. However, nothing is known about the synthesis of PI in this organism. Database mining revealed a putative TbPIS gene in the T. brucei genome and by recombinant expression and characterization it was shown to encode a catalytically active PIS, with a high specificity for myo-inositol. Immunofluorescence revealed that in T. brucei, PIS is found in both the endoplasmic reticulum and Golgi. We created a conditional double knockout of TbPIS in the bloodstream form of T. brucei, which when grown under non-permissive conditions, clearly showed that TbPIS is an essential gene. In vivo labelling of these conditional double knockout cells confirmed this result, showing a decrease in the amount of PI formed by the cells when grown under non-permissive conditions. Furthermore, quantitative and qualitative analysis by GLC-MS and ESI-MS/MS (electrospray ionization MS/MS) respectively showed a significant decrease (70%) in cellular PI, which appears to affect all major PI species equally. A consequence of this fall in PI level is a knock-on reduction in GPI biosynthesis which is essential for the parasite's survival. The results presented here show that PI synthesis is essential for bloodstream form T. brucei, and to our knowledge this is the first report of the dependence on PI synthesis of a protozoan parasite by genetic validation.
Collapse
Key Words
- bloodstream form
- essentiality
- glycosylphosphatidylinositol
- myo-inositol
- phosphatidylinositol synthase (pis)
- trypanosoma
- bip, endoplasmic reticulum luminal chaperone binding protein
- dag, diacylglycerol
- dapi, 4,6-diamidino-2-phenylindole
- er, endoplasmic reticulum
- esi-ms, electrospray ionization ms
- gpi, glycosylphosphatidylinositol
- ha, haemagglutinin
- hptlc, high-performance tlc
- hyg, hygromycin phosphotransferase
- iptg, isopropyl β-d-thiogalactoside
- lb, luria–bertani
- ni-nta, ni2+-nitrilotriacetate
- orf, open reading frame
- pac, puromycin acetyltransferase
- pi, phosphatidylinositol
- plc, phospholipase c
- pi-plc, pi-specific plc
- pis, pi synthase
- tbgrasp, t. brucei golgi matrix protein
- tbpis, t. brucei pi synthase
- tdb, trypanosome dilution buffer
- ti, tetracycline-inducible
- tritc, tetramethylrhodamine β-isothiocyanate
- utr, untranslated region
- vsg, variant-surface glycoprotein
Collapse
Affiliation(s)
- Kirstee L. Martin
- Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| | - Terry K. Smith
- Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| |
Collapse
|
25
|
Adragna NC, Ferrell CM, Zhang J, Di Fulvio M, Temprana CF, Sharma A, Fyffe REW, Cool DR, Lauf PK. Signal transduction mechanisms of K+-Cl- cotransport regulation and relationship to disease. Acta Physiol (Oxf) 2006; 187:125-39. [PMID: 16734749 DOI: 10.1111/j.1748-1716.2006.01560.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The K+-Cl- cotransport (COT) regulatory pathways recently uncovered in our laboratory and their implication in disease state are reviewed. Three mechanisms of K+-Cl- COT regulation can be identified in vascular cells: (1) the Li+-sensitive pathway, (2) the platelet-derived growth factor (PDGF)-sensitive pathway and (3) the nitric oxide (NO)-dependent pathway. Ion fluxes, Western blotting, semi-quantitative RT-PCR, immunofluorescence and confocal microscopy were used. Li+, used in the treatment of manic depression, stimulates volume-sensitive K+-Cl- COT of low K+ sheep red blood cells at cellular concentrations <1 mM and inhibits at >3 mM, causes cell swelling, and appears to regulate K+-Cl- COT through a protein kinase C-dependent pathway. PDGF, a potent serum mitogen for vascular smooth muscle cells (VSMCs), regulates membrane transport and is involved in atherosclerosis. PDGF stimulates VSM K+-Cl- COT in a time- and concentration-dependent manner, both acutely and chronically, through the PDGF receptor. The acute effect occurs at the post-translational level whereas the chronic effect may involve regulation through gene expression. Regulation by PDGF involves the signalling molecules phosphoinositides 3-kinase and protein phosphatase-1. Finally, the NO/cGMP/protein kinase G pathway, involved in vasodilation and hence cardiovascular disease, regulates K+-Cl- COT in VSMCs at the mRNA expression and transport levels. A complex and diverse array of mechanisms and effectors regulate K+-Cl- COT and thus cell volume homeostasis, setting the stage for abnormalities at the genetic and/or regulatory level thus effecting or being affected by various pathological conditions.
Collapse
Affiliation(s)
- N C Adragna
- Cell Biophysics Group, Wright State University School of Medicine, Dayton, OH 45435, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Ward P, Equinet L, Packer J, Doerig C. Protein kinases of the human malaria parasite Plasmodium falciparum: the kinome of a divergent eukaryote. BMC Genomics 2004; 5:79. [PMID: 15479470 PMCID: PMC526369 DOI: 10.1186/1471-2164-5-79] [Citation(s) in RCA: 376] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2004] [Accepted: 10/12/2004] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Malaria, caused by the parasitic protist Plasmodium falciparum, represents a major public health problem in the developing world. The P. falciparum genome has been sequenced, which provides new opportunities for the identification of novel drug targets. Eukaryotic protein kinases (ePKs) form a large family of enzymes with crucial roles in most cellular processes; hence malarial ePKS represent potential drug targets. We report an exhaustive analysis of the P. falciparum genomic database (PlasmoDB) aimed at identifying and classifying all ePKs in this organism. RESULTS Using a variety of bioinformatics tools, we identified 65 malarial ePK sequences and constructed a phylogenetic tree to position these sequences relative to the seven established ePK groups. Predominant features of the tree were: (i) that several malarial sequences did not cluster within any of the known ePK groups; (ii) that the CMGC group, whose members are usually involved in the control of cell proliferation, had the highest number of malarial ePKs; and (iii) that no malarial ePK clustered with the tyrosine kinase (TyrK) or STE groups, pointing to the absence of three-component MAPK modules in the parasite. A novel family of 20 ePK-related sequences was identified and called FIKK, on the basis of a conserved amino acid motif. The FIKK family seems restricted to Apicomplexa, with 20 members in P. falciparum and just one member in some other Apicomplexan species. CONCLUSION The considerable phylogenetic distance between Apicomplexa and other Eukaryotes is reflected by profound divergences between the kinome of malaria parasites and that of yeast or mammalian cells.
Collapse
Affiliation(s)
- Pauline Ward
- Wellcome Centre for Molecular Parasitology, University of Glasgow, 56 Dumbarton Road, Glasgow G11 6NU, Scotland, UK
| | - Leila Equinet
- INSERM U609, Wellcome Centre for Molecular Parasitology, University of Glasgow, 56 Dumbarton Road, Glasgow G11 6NU, Scotland, UK
| | - Jeremy Packer
- Division of Advanced Technologies, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60064, USA
| | - Christian Doerig
- INSERM U609, Wellcome Centre for Molecular Parasitology, University of Glasgow, 56 Dumbarton Road, Glasgow G11 6NU, Scotland, UK
| |
Collapse
|
27
|
Abstract
Parasitic protozoa are surrounded by membrane structures that have a different lipid and protein composition relative to membranes of the host. The parasite membranes are essential structurally and also for parasite specific processes, like host cell invasion, nutrient acquisition or protection against the host immune system. Furthermore, intracellular parasites can modulate membranes of their host, and trafficking of membrane components occurs between host membranes and those of the intracellular parasite. Phospholipids are major membrane components and, although many parasites scavenge these phospholipids from their host, most parasites also synthesise phospholipids de novo, or modify a large part of the scavenged phospholipids. It was recently shown that some parasites like Plasmodium have unique phospholipid metabolic pathways. This review will focus on new developments in research on phospholipid metabolism of parasitic protozoa in relation to parasite-specific membrane structures and function, as well as on several targets for interference with the parasite phospholipid metabolism with a view to developing new anti-parasitic drugs.
Collapse
Affiliation(s)
- Henri J Vial
- Dynamique Moléculaire des Interactions Membranaires, CNRS UMR 5539, cc107, Université Montpellier II, Place Eugène Bataillon, 34095 Montpellier, France.
| | | | | | | |
Collapse
|
28
|
El Alaoui H, Bata J, Peyret P, Vivarès CP. Encephalitozoon cuniculi (Microspora): characterization of a phospholipid metabolic pathway potentially linked to therapeutics. Exp Parasitol 2001; 98:171-9. [PMID: 11560410 DOI: 10.1006/expr.2001.4635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipid metabolism of the microsporidian Encephalitozoon cuniculi, an obligate intracellular parasite, has been investigated. Labeled precursor incorporation experiments have shown that phosphatidylserine decarboxylase and phosphatidylethanolamine N-methyltransferase are more active in cells infected by E. cuniculi than in uninfected cells. In contrast, no difference was observed in the activity of Kennedy pathway's enzymes, the mammalian pathway. This suggests the occurrence in microsporidia of a bacteria- and fungi-typical pathway for phospholipid synthesis, which is supported by the identification of two genes implicated in this pathway, the cds gene encoding the key enzyme CDP-diacylglycerol synthase (E.C. 2.7.7.41) and the pss gene for CDP-alcohol phosphatidyltransferase. The pss gene could encode phosphatidylserine synthase (E.C. 2.7.8.8.), which catalyses the de novo synthesis of phosphatidylserine in bacteria and fungi. The complete CDP-diacylglycerol synthase messenger has been isolated and shows very short 5' and 3' untranslated regions. This is strong evidence for the functionality of a metabolic pathway which could be a potential target against microsporidia which infect humans.
Collapse
Affiliation(s)
- H El Alaoui
- Laboratoire de Parasitologie Moléculaire et Cellulaire, LBP, UMR CNRS 6023, Biologie A, 63177 Aubière Cedex, France
| | | | | | | |
Collapse
|
29
|
Séron K, Dzierszinski F, Tomavo S. Molecular cloning, functional complementation in Saccharomyces cerevisiae and enzymatic properties of phosphatidylinositol synthase from the protozoan parasite Toxoplasma gondii. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:6571-9. [PMID: 11054108 DOI: 10.1046/j.1432-1327.2000.01749.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The obligate intracellular parasite Toxoplasma gondii, the causative agent of toxoplasmosis, switches between the rapidly dividing tachyzoite and the slowly replicating bradyzoite in intermediate hosts such as humans and domestic animals. We have recently identified a bradyzoite cDNA encoding a putative phosphatidylinositol (PtdIns) synthase using a subtractive library [Yahiaoui, B., Dzierszinski, F., Bernigaud, A., Slomianny, C., Camus, D., and Tomavo, S. (1999) Mol. Biochem. Parasitol. 99, 223-235]. Here, we report the cloning of another cDNA encoding PtdIns synthase that is exclusively expressed in the tachyzoite stage. The two transcripts are encoded by two different genes, which are stage-specifically regulated. The deduced amino-acid sequence (258 amino acids with a calculated total molecular mass of 27.8 kDa) of the tachyzoite-specific cDNA shares a significant degree of identity (between 26.5 and 30.1%) to the PtdIns synthases from human, rat, Arabidopsis thaliana and yeast. Interestingly, the putative protein encompasses an N-terminal extension that is approximately 40 amino-acids longer than that of PtdIns synthases from other organisms. Functional complementation realized by tetrad analysis of segregants of a Saccharomyces cerevisiae PtdIns synthase-deficient mutant (PIS1/pis1:kanMX4) showed that only the T. gondii putative PtdIns synthase truncated at its N-terminal extension is able to restore the viability of the cells. We demonstrate that this protein expressed in yeast transformants is functionally active in the membrane preparation and requires manganese and magnesium ions for activity. To our knowledge, this is the first report on the molecular cloning and functional analysis of a gene encoding a PtdIns synthase in protozoan parasites.
Collapse
Affiliation(s)
- K Séron
- Laboratoire de Chimie Biologique, UMR 8576 CNRS-Université des Sciences et Technologies de Lille France
| | | | | |
Collapse
|
30
|
Martin D, Gannoun-Zaki L, Bonnefoy S, Eldin P, Wengelnik K, Vial H. Characterization of Plasmodium falciparum CDP-diacylglycerol synthase, a proteolytically cleaved enzyme. Mol Biochem Parasitol 2000; 110:93-105. [PMID: 10989148 DOI: 10.1016/s0166-6851(00)00260-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cytidine diphosphate-diacylglycerol (CDP-DAG), an obligatory intermediate compound in the biosynthesis of the major anionic and zwitterionic phospholipids, is synthesized by CDP-DAG synthase (CDS). The gene encoding CDS was isolated from the human malaria parasite Plasmodium falciparum, based on sequence conservation to CDS from other organisms. The P. falciparum gene is located as a single copy on chromosome 14. The open reading frame (ORF) of PfCDS gene encodes a putative protein of 667 amino acids and 78 kDa. Only the C-terminal 422 amino acids share 40% homology with eukaryotic CDSs. The very long and non-conserved N-terminal region of 245 amino acids is hydrophilic and contains asparagine-rich and repetitive sequences. Two mRNA of 3.5 and 4 kb were detected. Transcription is developmentally regulated during the asexual intraerythrocytic cycle, being the weakest in the ring-stage. PfCDS enzyme activities in infected erythrocytes correlates with the transcription pattern, consistent with an increased synthesis of phospholipids in trophozoites and schizonts. Antisera raised against two synthetic peptides from the C-terminal region of PfCDS detected a single protein of 51 kDa in Western blot analysis, specific for parasitized erythrocytes. A protein of 28 kDa was recognized by an antiserum against an N-terminal peptide, indicating that PfCDS is proteolytically processed. Expression of 51- and 28-kDa proteins was developmentally regulated similar to regulation of the transcripts and the enzyme activity. The conserved C-terminal region of PfCDS, cloned into a eukaryote expression vector and transfected in COS-7 cells, showed a two-fold increase CDP-DAG synthase activities, indicating that the isolated gene most likely encoded the P. falciparum CDS enzyme.
Collapse
Affiliation(s)
- D Martin
- UMR 5539, CNRS/Université Montpellier II, cc 107, Place E. Bataillon, 34095 Cedex 05, Montpellier, France
| | | | | | | | | | | |
Collapse
|
31
|
Antonsson B. Phosphatidylinositol synthase from mammalian tissues. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1348:179-86. [PMID: 9370331 DOI: 10.1016/s0005-2760(97)00105-7] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Phosphatidylinositol synthase (CDP-diacylglycerol:myo-inositol 3-phosphatidyl-transferase, EC 2.7.8.11) is a 24-kDa membrane-bound enzyme. It is present in all mammalian cells and is localized predominantly to the endoplasmic reticulum. The enzyme performs the last step in the de novo biosynthesis of the phospholipid phosphatidylinositol by catalyzing the condensation of CDP-diacylglycerol and myo-inositol to form the products phosphatidylinositol and CMP. Phosphatidylinositol, apart from being an essential membrane phospholipid, is involved in protein membrane anchoring and is the precursor for the second messengers inositol-tri-phosphate and diacylglycerol.
Collapse
Affiliation(s)
- B Antonsson
- Geneva Biomedical Research Institute, Glaxo Wellcome R&D S.A., Switzerland.
| |
Collapse
|
32
|
Abstract
Over the past few years, several reports have been published about the characterization of Plasmodium genes that are thought, on the basis of sequence homology with eukaryotic genes of known function, to be involved in the regulation of growth and differentiation of the parasite. Taken together with phenomenological observations on the regulation of developmental stages in the malaria life cycle, these data form the basis of an informative, albeit incomplete, picture of signal transtruction in Plasmodium. Christian Doerig here reviews Plasmodium elements that are presumably part of major regulatory pathways conserved in eukaryotes, and addresses the problem of how to pursue such studies beyond the stage of gene identification.
Collapse
Affiliation(s)
- C D Doerig
- Institut National de la Santé et de la Recherche Médicale (INSERM), Unité 313. Centre Hospitalier Universitaire Pitié-Salpêtrière, 91 Boulevard de l'Hôpital, 75013 Paris, France
| |
Collapse
|
33
|
Sinden RE, Butcher GA, Billker O, Fleck SL. Regulation of infectivity of Plasmodium to the mosquito vector. ADVANCES IN PARASITOLOGY 1996; 38:53-117. [PMID: 8701799 DOI: 10.1016/s0065-308x(08)60033-0] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- R E Sinden
- Department of Biology, Imperial College of Science, Technology and Medicine, South Kensington, London, UK
| | | | | | | |
Collapse
|