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Roy M, Chakraborty S, Kumar Srivastava S, Kaushik S, Jyoti A, Kumar Srivastava V. Entamoeba histolytica induced NETosis and the dual role of NETs in amoebiasis. Int Immunopharmacol 2023; 118:110100. [PMID: 37011501 DOI: 10.1016/j.intimp.2023.110100] [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: 11/28/2022] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 04/04/2023]
Abstract
Entamoeba histolytica (Eh), a microaerophilic parasite, causes deadly enteric infections that result in Amoebiasis. Every year, the count of invasive infections reaches 50 million approximately and 40,000 to 1,00,000 deaths occurring due to amoebiasis are reported globally. Profound inflammation is the hallmark of severe amoebiasis which is facilitated by immune first defenders, neutrophils. Due to size incompatibility, neutrophils are unable to phagocytose Eh and thus, came up with the miraculous antiparasitic mechanism of neutrophil extracellular traps (NETs). This review provides an in-depth analysis of NETosis induced by Eh including the antigens involved in the recognition of Eh and the biochemistry of NET formation. Additionally, it underscores its novelty by describing the dual role of NETs in amoebiasis where it acts as a double-edged sword in terms of both clearing and exacerbating amoebiasis. It also provides a comprehensive account of the virulence factors discovered to date that are implicated directly and indirectly in the pathophysiology of Eh infections through the lens of NETs and can be interesting drug targets.
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Affiliation(s)
- Mrinalini Roy
- Amity Institute of Biotechnology, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur-Delhi Highway, Jaipur, India
| | - Shreya Chakraborty
- Amity Institute of Biotechnology, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur-Delhi Highway, Jaipur, India
| | | | - Sanket Kaushik
- Amity Institute of Biotechnology, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur-Delhi Highway, Jaipur, India
| | - Anupam Jyoti
- Department of Biotechnology, University Institute of Biotechnology, Chandigarh University, NH-95, Chandigarh-Ludhiana Highway, Mohali, India
| | - Vijay Kumar Srivastava
- Amity Institute of Biotechnology, Amity University Rajasthan, Kant Kalwar, NH-11C, Jaipur-Delhi Highway, Jaipur, India.
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Galán-Vásquez E, Gómez-García MDC, Pérez-Rueda E. A landscape of gene regulation in the parasitic amoebozoa Entamoeba spp. PLoS One 2022; 17:e0271640. [PMID: 35913975 PMCID: PMC9342746 DOI: 10.1371/journal.pone.0271640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 07/05/2022] [Indexed: 11/27/2022] Open
Abstract
Entamoeba are amoeboid extracellular parasites that represent an important group of organisms for which the regulatory networks must be examined to better understand how genes and functional processes are interrelated. In this work, we inferred the gene regulatory networks (GRNs) in four Entamoeba species, E. histolytica, E. dispar, E. nuttalli, and E. invadens, and the GRN topological properties and the corresponding biological functions were evaluated. From these analyses, we determined that transcription factors (TFs) of E. histolytica, E. dispar, and E. nuttalli are associated mainly with the LIM family, while the TFs in E. invadens are associated with the RRM_1 family. In addition, we identified that EHI_044890 regulates 121 genes in E. histolytica, EDI_297980 regulates 284 genes in E. dispar, ENU1_120230 regulates 195 genes in E. nuttalli, and EIN_249270 regulates 257 genes in E. invadens. Finally, we identified that three types of processes, Macromolecule metabolic process, Cellular macromolecule metabolic process, and Cellular nitrogen compound metabolic process, are the main biological processes for each network. The results described in this work can be used as a basis for the study of gene regulation in these organisms.
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Affiliation(s)
- Edgardo Galán-Vásquez
- Departamento de Ingeniería de Sistemas Computacionales y Automatización, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, México
- * E-mail: (EG-V); (EP-R)
| | - María del Consuelo Gómez-García
- Laboratorio de Biomedicina Molecular, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Ciudad de México, México
| | - Ernesto Pérez-Rueda
- Unidad Académica Yucatán, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Mérida, Yucatán, México
- * E-mail: (EG-V); (EP-R)
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Kumar N, Rath PP, Aggarwal P, Maiti S, Bhavesh NS, Gourinath S. Unravelling the Biology of EhActo as the First Cofilin From Entamoeba histolytica. Front Cell Dev Biol 2022; 10:785680. [PMID: 35281106 PMCID: PMC8914023 DOI: 10.3389/fcell.2022.785680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 02/09/2022] [Indexed: 11/13/2022] Open
Abstract
Actin-depolymerising factors (ADF) are a known family of proteins that regulate actin dynamics. Actin regulation is critical for primitive eukaryotes since it drives their key cellular processes. Entamoeba histolytica, a protist human pathogen harbours eleven proteins within this family, however, with no actin depolymerising protein reported to date. We present here the NMR model of EhActo, the first Cofilin from E. histolytica that severs actin filaments and also participates in cellular events like phagocytosis and pseudopod formation. The model typically represents the ADF-homology domain compared to other cofilins. Uniquely, EhActo lacks the critical Serine3 residue present in all known actophorins mediating its phospho-regulation. The second mode of regulation that cofilin’s are subjected to is via their interaction with 14-3-3 proteins through the phosphorylated Serine residue and a consensus binding motif. We found a unique interaction between EhActo and 14-3-3 without the presence of the consensus motif or the phosphorylated Serine. These interesting results present unexplored newer mechanisms functional in this pathogen to regulate actophorin. Through our structural and biochemical studies we have deciphered the mechanism of action of EhActo, implicating its role in amoebic biology.
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Affiliation(s)
- Nitesh Kumar
- Department of Pathology, Indira Gandhi Institute of Medical Sciences, Patna, India
- International Centre for Genetic Engineering and Biotechnology, New Delhi, India
- *Correspondence: Nitesh Kumar, ; Samudrala Gourinath,
| | | | - Priyanka Aggarwal
- International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Sankar Maiti
- Indian Institute of Science, Education and Research, Kolkata, India
| | - Neel Sarovar Bhavesh
- International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Samudrala Gourinath
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
- *Correspondence: Nitesh Kumar, ; Samudrala Gourinath,
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Salgado-Martínez AI, Avila-Bonilla RG, Ramírez-Moreno E, Castañón-Sánchez CA, López-Camarillo C, Marchat LA. Unraveling the relevance of the polyadenylation factor EhCFIm25 in Entamoeba histolytica through proteomic analysis. FEBS Open Bio 2021; 11:2819-2835. [PMID: 34486252 PMCID: PMC8487052 DOI: 10.1002/2211-5463.13287] [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] [Received: 05/26/2021] [Revised: 08/06/2021] [Accepted: 09/02/2021] [Indexed: 11/16/2022] Open
Abstract
We recently reported that silencing of the polyadenylation factor EhCFIm25 in Entamoeba histolytica, the protozoan which causes human amoebiasis, affects trophozoite proliferation, death, and virulence, suggesting that EhCFIm25 may have potential as a new biochemical target. Here, we performed a shotgun proteomic analysis to identify modulated proteins that could explain this phenotype. Data are available via ProteomeXchange with identifier PXD027784. Our results revealed changes in the abundance of 75 proteins. Interestingly, STRING analysis, functional GO‐term annotations, KEGG analyses, and literature review showed that modulated proteins are mainly related to glycolysis and carbon metabolism, cytoskeleton dynamics, and parasite virulence, as well as gene expression and protein modifications. Further studies are needed to confirm the hypotheses emerging from this proteomic analysis, to thereby acquire a comprehensive view of the molecular mechanisms involved.
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Affiliation(s)
| | | | - Esther Ramírez-Moreno
- Laboratorio de Biomedicina Molecular II, ENMH, Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - César López-Camarillo
- Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México (UACM), Mexico
| | - Laurence A Marchat
- Laboratorio de Biomedicina Molecular II, ENMH, Instituto Politécnico Nacional, Mexico City, Mexico
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Ochoa-Maganda VY, Rangel-Castañeda IA, Suárez-Rico DO, Cortés-Zárate R, Hernández-Hernández JM, Pérez-Rangel A, Chiquete-Félix N, León-Ávila G, González-Pozos S, Gaona-Bernal J, Castillo-Romero A. Antigiardial Activity of Acetylsalicylic Acid Is Associated with Overexpression of HSP70 and Membrane Transporters. Pharmaceuticals (Basel) 2020; 13:ph13120440. [PMID: 33287104 PMCID: PMC7761642 DOI: 10.3390/ph13120440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/29/2020] [Accepted: 11/30/2020] [Indexed: 12/19/2022] Open
Abstract
Giardia lamblia is a flagellated protozoan responsible for giardiasis, a worldwide diarrheal disease. The adverse effects of the pharmacological treatments and the appearance of drug resistance have increased the rate of therapeutic failures. In the search for alternative therapeutics, drug repositioning has become a popular strategy. Acetylsalicylic acid (ASA) exhibits diverse biological activities through multiple mechanisms. However, the full spectrum of its activities is incompletely understood. In this study we show that ASA displayed direct antigiardial activity and affected the adhesion and growth of trophozoites in a time-dose-dependent manner. Electron microscopy images revealed remarkable morphological alterations in the membrane, ventral disk, and caudal region. Using mass spectrometry and real-time quantitative reverse transcription (qRT-PCR), we identified that ASA induced the overexpression of heat shock protein 70 (HSP70). ASA also showed a significant increase of five ATP-binding cassette (ABC) transporters (giABC, giABCP, giMDRP, giMRPL and giMDRAP1). Additionally, we found low toxicity on Caco-2 cells. Taken together, these results suggest an important role of HSPs and ABC drug transporters in contributing to stress tolerance and protecting cells from ASA-induced stress.
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Affiliation(s)
- Verónica Yadira Ochoa-Maganda
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, Col. Independencia, Guadalajara, Jalisco 44340, Mexico; (V.Y.O.-M.); (D.O.S.-R.)
| | - Itzia Azucena Rangel-Castañeda
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Ciudad de México 07360, Mexico; (I.A.R.-C.); (J.M.H.-H.); (A.P.-R.)
| | - Daniel Osmar Suárez-Rico
- Departamento de Fisiología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, Col. Independencia, Guadalajara, Jalisco 44340, Mexico; (V.Y.O.-M.); (D.O.S.-R.)
| | - Rafael Cortés-Zárate
- Departamento de Microbiología y Patología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, Col. Independencia, Guadalajara, Jalisco 44340, Mexico; (R.C.-Z.); (J.G.-B.)
| | - José Manuel Hernández-Hernández
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Ciudad de México 07360, Mexico; (I.A.R.-C.); (J.M.H.-H.); (A.P.-R.)
| | - Armando Pérez-Rangel
- Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Ciudad de México 07360, Mexico; (I.A.R.-C.); (J.M.H.-H.); (A.P.-R.)
| | - Natalia Chiquete-Félix
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico;
| | - Gloria León-Ávila
- Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, IPN, Carpio y Plan de Ayala S/N, Casco de Santo Tomás, Ciudad de México 11340, Mexico;
| | - Sirenia González-Pozos
- Unidad de Microscopía Electrónica LaNSE, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, Ciudad de México 07360, Mexico;
| | - Jorge Gaona-Bernal
- Departamento de Microbiología y Patología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, Col. Independencia, Guadalajara, Jalisco 44340, Mexico; (R.C.-Z.); (J.G.-B.)
| | - Araceli Castillo-Romero
- Departamento de Microbiología y Patología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Sierra Mojada 950, Col. Independencia, Guadalajara, Jalisco 44340, Mexico; (R.C.-Z.); (J.G.-B.)
- Correspondence: ; Tel.: +52-1-331-058-5200
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6
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Rath PP, Gourinath S. The actin cytoskeleton orchestra in Entamoeba histolytica. Proteins 2020; 88:1361-1375. [PMID: 32506560 DOI: 10.1002/prot.25955] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/17/2020] [Accepted: 05/27/2020] [Indexed: 12/14/2022]
Abstract
Years of evolution have kept actin conserved throughout various clades of life. It is an essential protein starring in many cellular processes. In a primitive eukaryote named Entamoeba histolytica, actin directs the process of phagocytosis. A finely tuned coordination between various actin-binding proteins (ABPs) choreographs this process and forms one of the virulence factors for this protist pathogen. The ever-expanding world of ABPs always has space to accommodate new and varied types of proteins to the earlier existing repertoire. In this article, we report the identification of 390 ABPs from Entamoeba histolytica. These proteins are part of diverse families that have been known to regulate actin dynamics. Most of the proteins are primarily uncharacterized in this organism; however, this study aims to annotate the ABPs based on their domain arrangements. A unique characteristic about some of the ABPs found is the combination of domains present in them unlike any other reported till date. Calponin domain-containing proteins formed the largest group among all types with 38 proteins, followed by 29 proteins with the infamous BAR domain in them, and 23 proteins belonging to actin-related proteins. The other protein families had a lesser number of members. Presence of exclusive domain arrangements in these proteins could guide us to yet unknown actin regulatory mechanisms prevalent in nature. This article is the first step to unraveling them.
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Marchat LA, Hernández-de la Cruz ON, Ramírez-Moreno E, Silva-Cázares MB, López-Camarillo C. Proteomics approaches to understand cell biology and virulence of Entamoeba histolytica protozoan parasite. J Proteomics 2020; 226:103897. [PMID: 32652218 DOI: 10.1016/j.jprot.2020.103897] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/09/2020] [Accepted: 07/06/2020] [Indexed: 11/19/2022]
Abstract
Entamoeba histolytica is the primitive eukaryotic parasite responsible of human amoebiasis, a disease characterized by bloody intestinal diarrhea and invasive extraintestinal illness. The knowledge of the complete genome sequence of virulent E. histolytica and related non-pathogenic species allowed the development of novel genome-wide methodological approaches including protein expression profiling and cellular proteomics in the so called post-genomic era. Proteomics studies have greatly increased our understanding of the cell biology of this ancient parasite. This review summarizes the current works concerning proteomics studies on cell biology, life cycle, virulence and pathogenesis, novel therapies, and protein expression regulation mechanisms in E. histolytica parasite. Also, we discuss the use of proteomics data for the development of novel therapies, the identification of potential disease biomarkers and differential diagnosis between species. SIGNIFICANCE: Entamoeba histolytica is the unicellular protozoan parasite responsible of human amoebiasis, a serious disease with worldwide distribution characterized by bloody intestinal diarrhea and invasive extraintestinal illness including peritonitis and liver, pulmonary and brain abscesses. The post-genomic era allowed the development of proteomic studies including protein expression profiling and cellular proteomics. These proteomics studies have greatly increased our understanding on cell biology, life cycle (cyst-trophozoite conversion), virulence, pathogenesis, novel therapies, and protein expression regulation mechanisms in E. histolytica. Importantly, proteomics has revealed the identity of proteins related to novel therapies, and the identification of potential disease biomarkers and proteins with use in diagnosis between species. Hopefully in the coming years, and through the use of more sophisticated omics tools, including deep proteomics, a more complete set of proteins involved in the aforementioned cellular processes can be obtained to understand the biology of this ancient eukaryote.
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Affiliation(s)
- Laurence A Marchat
- Programa en Biomedicina Molecular y Red de Biotecnología, ENMH-Instituto Politécnico Nacional, CDMX, México.
| | | | - Esther Ramírez-Moreno
- Programa en Biomedicina Molecular y Red de Biotecnología, ENMH-Instituto Politécnico Nacional, CDMX, México
| | - Macrina B Silva-Cázares
- Doctorado Institucional en Ingeniería y Ciencias de Materiales, Coordinación Académica Región Altiplano, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - César López-Camarillo
- Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México, CDMX, México.
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Knockdown of Five Genes Encoding Uncharacterized Proteins Inhibits Entamoeba histolytica Phagocytosis of Dead Host Cells. Infect Immun 2016; 84:1045-1053. [PMID: 26810036 DOI: 10.1128/iai.01325-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 01/15/2016] [Indexed: 12/17/2022] Open
Abstract
Entamoeba histolytica is the protozoan parasite that causes invasive amebiasis, which is endemic to many developing countries and characterized by dysentery and liver abscesses. The virulence of E. histolytica correlates with the degree of host cell engulfment, or phagocytosis, and E. histolytica phagocytosis alters amebic gene expression in a feed-forward manner that results in an increased phagocytic ability. Here, we used a streamlined RNA interference screen to silence the expression of 15 genes whose expression was upregulated in phagocytic E. histolytica trophozoites to determine whether these genes actually function in the phagocytic process. When five of these genes were silenced, amebic strains with significant decreases in the ability to phagocytose apoptotic host cells were produced. Phagocytosis of live host cells, however, was largely unchanged, and the defects were surprisingly specific for phagocytosis. Two of the five encoded proteins, which we named E. histolytica ILWEQ (EhILWEQ) and E. histolytica BAR (EhBAR), were chosen for localization via SNAP tag labeling and localized to the site of partially formed phagosomes. Therefore, both EhILWEQ and EhBAR appear to contribute to E. histolytica virulence through their function in phagocytosis, and the large proportion (5/15 [33%]) of gene-silenced strains with a reduced ability to phagocytose host cells validates the previously published microarray data set demonstrating feed-forward control of E. histolytica phagocytosis. Finally, although only limited conclusions can be drawn from studies using the virulence-deficient G3 Entamoeba strain, the relative specificity of the defects induced for phagocytosis of apoptotic cells but not healthy cells suggests that cell killing may play a rate-limiting role in the process of Entamoeba histolytica host cell engulfment.
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Proteomic profiling reveals that EhPC4 transcription factor induces cell migration through up-regulation of the 16-kDa actin-binding protein EhABP16 in Entamoeba histolytica. J Proteomics 2014; 111:46-58. [PMID: 24721673 DOI: 10.1016/j.jprot.2014.03.041] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 03/24/2014] [Accepted: 03/28/2014] [Indexed: 11/20/2022]
Abstract
UNLABELLED Actin cytoskeleton is an essential structure involved in cell migration and invasion in parasites. In Entamoeba histolytica, the protozoan parasite causing human amoebiasis, the mechanisms underlying the expression of migration-related genes are poorly understood. Here, we investigated the biological effects of ectopic overexpression of EhPC4 (positive coactivator 4) in cell migration of E. histolytica trophozoites. Using differential in gel two-dimensional electrophoresis, 33 modulated proteins were detected in EhPC4-overexpressing cells. By electrospray ionization tandem mass spectrometry (ESI-MS/MS) analysis, 16 of these proteins were identified. Interestingly, four up-regulated proteins involved in cytoskeleton organization and cell migration were identified. Particularly, we found the up-regulation of a 16-kDa actin-binding protein (EhABP16) which is a putative member of the cofilin/tropomyosin family involved in actin polymerization. EhPC4 overexpression induced a significant increase in migration of trophozoites and in the destruction of human SW480 colon cells. Consistently, silencing of gene expression by RNA interference of EhABP16 significantly impairs cell migration. These changes were associated to alterations in the organization of actin cytoskeleton, and suppression of uropod-like structure formation in EhABP16-deficient cells. In summary, we have uncovered novel proteins modulated by EhPC4, including EhABP16, with a potential role in cell migration, cytopathogenicity and virulence in E. histolytica. BIOLOGICAL SIGNIFICANCE The human pathogen Entamoeba histolytica infects around 50million people worldwide resulting in 40,000-100,000 deaths annually. Cell motility is a complex trait that is critical for parasites adaptation, spread and invasion processes into host tissues; it has been associated with virulence. In this study, we used a differential proteomic approach to demonstrate that E. histolytica EhPC4 induces changes in the expression of actin cytoskeleton proteins, including EhABP16, promoting a significant increase in cell motility and destruction of intestinal human cells. Particularly, we demonstrated for the first time that abrogation of EhABP16 impairs cell migration by altering the actin cytoskeleton dynamics and uropod-like structure formation in trophozoites. These data contribute to the understanding of molecular mechanisms that regulate virulence properties in this neglected protozoan parasite.
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Biller L, Matthiesen J, Kühne V, Lotter H, Handal G, Nozaki T, Saito-Nakano Y, Schümann M, Roeder T, Tannich E, Krause E, Bruchhaus I. The cell surface proteome of Entamoeba histolytica. Mol Cell Proteomics 2013; 13:132-44. [PMID: 24136294 PMCID: PMC3879609 DOI: 10.1074/mcp.m113.031393] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Surface molecules are of major importance for host-parasite interactions. During Entamoeba histolytica infections, these interactions are predicted to be of prime importance for tissue invasion, induction of colitis and liver abscess formation. To date, however, little is known about the molecules involved in these processes, with only about 20 proteins or protein families found exposed on the E. histolytica surface. We have therefore analyzed the complete surface proteome of E. histolytica. Using cell surface biotinylation and mass spectrometry, 693 putative surface-associated proteins were identified. In silico analysis predicted that ∼26% of these proteins are membrane-associated, as they contain transmembrane domains and/or signal sequences, as well as sites of palmitoylation, myristoylation, or prenylation. An additional 25% of the identified proteins likely represent nonclassical secreted proteins. Surprisingly, no membrane-association sites could be predicted for the remaining 49% of the identified proteins. To verify surface localization, 23 proteins were randomly selected and analyzed by immunofluorescence microscopy. Of these 23 proteins, 20 (87%) showed definite surface localization. These findings indicate that a far greater number of E. histolytica proteins than previously supposed are surface-associated, a phenomenon that may be based on the high membrane turnover of E. histolytica.
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Affiliation(s)
- Laura Biller
- Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Str. 74, 20359 Hamburg, Germany
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A genome-wide over-expression screen identifies genes involved in phagocytosis in the human protozoan parasite, Entamoeba histolytica. PLoS One 2012; 7:e43025. [PMID: 22905196 PMCID: PMC3419234 DOI: 10.1371/journal.pone.0043025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 07/16/2012] [Indexed: 11/23/2022] Open
Abstract
Functional genomics and forward genetics seek to assign function to all known genes in a genome. Entamoeba histolytica is a protozoan parasite for which forward genetics approaches have not been extensively applied. It is the causative agent of amoebic dysentery and liver abscess, and infection is prevalent in developing countries that cannot prevent its fecal-oral spread. It is responsible for considerable global morbidity and mortality. Given that the E. histolytica genome has been sequenced, it should be possible to apply genomic approaches to discover gene function. We used a genome-wide over-expression screen to uncover genes regulating an important virulence function of E. histolytica, namely phagocytosis. We developed an episomal E. histolytica cDNA over-expression library, transfected the collection of plasmids into trophozoites, and applied a high-throughput screen to identify phagocytosis mutants in the population of over-expressing cells. The screen was based on the phagocytic uptake of human red blood cells loaded with the metabolic toxin, tubercidin. Expression plasmids were isolated from trophozoites that survived exposure to tubercidin-charged erythrocytes (phagocytosis mutants), and the cDNAs were sequenced. We isolated the gene encoding profilin, a well-characterized cytoskeleton-regulating protein with a known role in phagocytosis. This supports the validity of our approach. Furthermore, we assigned a phagocytic role to several genes not previously known to function in this manner. To our knowledge, this is the first genome-wide forward genetics screen to be applied to this pathogen. The study demonstrates the power of forward genetics in revealing genes regulating virulence in E. histolytica. In addition, the study validates an E. histolytica cDNA over-expression library as a valuable tool for functional genomics.
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Wilson IW, Weedall GD, Hall N. Host-Parasite interactions in Entamoeba histolytica and Entamoeba dispar: what have we learned from their genomes? Parasite Immunol 2012; 34:90-9. [PMID: 21810102 PMCID: PMC3378717 DOI: 10.1111/j.1365-3024.2011.01325.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Invasive amoebiasis caused by Entamoeba histolytica is a major global health problem. Virulence is a rare outcome of infection, occurring in fewer than 1 in 10 infections. Not all strains of the parasite are equally virulent, and understanding the mechanisms and causes of virulence is an important goal of Entamoeba research. The sequencing of the genome of E. histolytica and the related avirulent species Entamoeba dispar has allowed whole-genome-scale analyses of genetic divergence and differential gene expression to be undertaken. These studies have helped elucidate mechanisms of virulence and identified genes differentially expressed in virulent and avirulent parasites. Here, we review the current status of the E. histolytica and E. dispar genomes and the findings of a number of genome-scale studies comparing parasites of different virulence.
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Affiliation(s)
- I W Wilson
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
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Biller L, Schmidt H, Krause E, Gelhaus C, Matthiesen J, Handal G, Lotter H, Janssen O, Tannich E, Bruchhaus I. Comparison of two genetically related Entamoeba histolytica cell lines derived from the same isolate with different pathogenic properties. Proteomics 2009; 9:4107-20. [PMID: 19688750 DOI: 10.1002/pmic.200900022] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Entamoeba histolytica is known for its extraordinary capacity to destroy human tissues, leading to invasive diseases such as ulcerative colitis or extra-intestinal abscesses. In order to identify the virulence factors of this parasite phenotypes and proteomes of two recently identified genetically related cell lines (A and B), derived from the laboratory E. histolytica isolate HM-1:IMSS, were compared. Both cell lines are indistinguishable on the basis of highly polymorphic tandem repeat DNA sequences. However, cell line A is incapable to induce liver abscesses in experimentally infected rodents, whereas cell line B provokes considerable abscesses. Phenotypic analyses revealed increased hemolytic activity, lower growth rate, smaller cell size, reduced cysteine peptidase activity and lower resistance to nitric oxide stress for cell line A. In contrast, no differences between the two cell lines were found for cytopathic activity, erythrophagocytosis, digestion of erythrocytes or resistance to complement, hydrogen peroxide and superoxide radical anions. Proteomic comparison by 2-D DIGE followed by MS, identified a total of 21 proteins with higher abundance in cell line A and ten proteins with higher abundance in cell line B. Remarkably, three differentially up-regulated antioxidants were exclusively found in the pathogenic cell line B. Notably, only for two differentially regulated proteins, namely a Fe-hydrogenase and a C2 domain protein, a similar type was found at the level of transcription. Summarized, a defined set of different proteins could be identified between cell lines A and B. These molecules may have an important role in amoeba pathogenicity.
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Affiliation(s)
- Laura Biller
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
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Lejeune M, Rybicka JM, Chadee K. Recent discoveries in the pathogenesis and immune response toward Entamoeba histolytica. Future Microbiol 2009; 4:105-18. [PMID: 19207103 DOI: 10.2217/17460913.4.1.105] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Entamoeba histolytica is an enteric dwelling human protozoan parasite that causes the disease amoebiasis, which is endemic in the developing world. Over the past four decades, considerable effort has been made to understand the parasite and the disease. Improved diagnostics can now differentiate pathogenic E. histolytica from that of the related but nonpathogenic Entamoeba dispar, thus minimizing screening errors. Classically, the triad of Gal-lectin, cysteine proteinases and amoebapores of the parasite were thought to be the major proteins involved in the pathogenesis of amoebiasis. However, other amoebic molecules such as lipophosphopeptidoglycan, perioxiredoxin, arginase, and lysine and glutamic acid-rich proteins are also implicated. Recently, the genome of E. histolytica has been sequenced, which has widened our scope to study additional virulence factors. E. histolytica genome-based approaches have now confirmed the presence of Golgi apparatus-like vesicles and the machinery for glycosylation, thus improving the chances of identifying potential drug targets for chemotherapeutic intervention. Apart from Gal-lectin-based vaccines, promising vaccine targets such as serine-rich E. histolytica protein have yielded encouraging results. Considerable efforts have also been made to skew vaccination responses towards appropriate T-helper cell immunity that could augment the efficacy of vaccine candidates under study. Thus, ongoing efforts mining the information made available with the sequencing of the E. histolytica genome will no doubt identify and characterize other important potential vaccine/drug targets and lead to effective immunologic strategies for the control of amoebiasis.
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Affiliation(s)
- Manigandan Lejeune
- University of Calgary, Department of Microbiology & Infectious Diseases, Calgary, AB, T2N 4N1, Canada.
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Mirelman D, Anbar M, Bracha R. Epigenetic transcriptional gene silencing in Entamoeba histolytica. IUBMB Life 2008; 60:598-604. [PMID: 18493998 DOI: 10.1002/iub.96] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The human intestinal pathogen Entamoeba histolytica has a number of virulence factors which can cause damage to the host. Transcriptional silencing of the gene coding for one of its major toxic molecules, the amoebapore (Ehap-a), occurred following the transfection of amoebic trophozoites with a plasmid containing the 5' promoter region of Ehap-a as well as a truncated segment of a neighboring, upstream SINE1 element that is transcribed from the opposite strand. Silencing was dependent on the presence of the truncated SINE1 sequences. Small amounts of short (approximately 140 n), ssRNA molecules with homology to SINE1 were detected in the silenced amoeba but no siRNA. The silenced Ehap-a gene domain had a chromatin modification indicating transcriptional inactivation without any DNA methylation. Removal of the plasmid did not restore transcription of Ehap-a. Transcription analysis by microarrays revealed that a number of additional genes were silenced and some were also up-regulated. Transfections of amoeba which already had a silenced Ehap-a, with a plasmid containing a second gene ligated to the 5' upstream region of Ehap-a, enabled the silencing, in-trans, of other genes of choice. The nonvirulent phenotype of the gene-silenced amoeba was demonstrated in various assays and the results suggest that they may have a potential use for vaccination.
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Affiliation(s)
- David Mirelman
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
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Abstract
PURPOSE OF REVIEW Entamoeba histolytica is an important global pathogen and a leading cause of parasitic death worldwide. This article summarizes significant research findings over the last year. RECENT FINDINGS Efforts have focused primarily on identification of novel virulence determinants in E. histolytica, transcriptional profiling during tissue invasion and stage conversion, and characterization of basic cell biological processes. Additionally, new techniques for gene silencing have been identified. SUMMARY A comprehensive examination of the parasite lifestyle on a whole genome level has been undertaken, allowing identification of new virulence genes and signaling pathways and processes relevant to amebic biology.
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Entamoeba histolytica encodes unique formins, a subset of which regulates DNA content and cell division. Infect Immun 2008; 76:2368-78. [PMID: 18347041 DOI: 10.1128/iai.01449-07] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The formin family of proteins mediates dynamic changes in actin assembly in eukaryotes, and therefore it is important to understand the function of these proteins in Entamoeba histolytica, where actin forms the major cytoskeletal network. In this study we have identified the formin homologs encoded in the E. histolytica genome based on sequence analysis. Using multiple tools, we have analyzed the primary sequences of the eight E. histolytica formins and discovered three subsets: (i) E. histolytica formin-1 to -3 (Ehformin-1 to -3), (ii) Ehformin-4, and (iii) Ehformin-5 to -8. Two of these subsets (Ehformin-1 to -3 and Ehformin-4) showed significant sequence differences from their closest homologs, while Ehformin-5 to -8 were unique among all known formins. Since Ehformin-1 to -3 showed important sequence differences from Diaphanous-related formins (DRFs), we have studied the functions of Ehformin-1 and -2 in E. histolytica transformants. Like other DRFs, Ehformin-1 and -2 associated with F-actin in response to serum factors, in pseudopodia, in pinocytic and phagocytic vesicles, and at cell division sites. Ehformin-1 and -2 also localized with the microtubular assembly in the nucleus, indicating their involvement in genome segregation. While increased expression of Ehformin-1 and -2 did not affect phagocytosis or motility, it clearly showed an increase in the number of binucleated cells, the number of nuclei in multinucleated cells, and the average DNA content of each nucleus, suggesting that these proteins regulate both mitosis and cytokinesis in E. histolytica.
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