1
|
Watanabe N, Nakada-Tsukui K, Nozaki T. Molecular Dissection of Phagocytosis by Proteomic Analysis in Entamoeba histolytica. Genes (Basel) 2023; 14:genes14020379. [PMID: 36833306 PMCID: PMC9957367 DOI: 10.3390/genes14020379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/24/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Entamoeba histolytica is the enteric protozoan parasite responsible for amebiasis. Trophozoites of E. histolytica ingest human cells in the intestine and other organs, which is the hallmark of its pathogenesis. Phagocytosis and trogocytosis are pivotal biological functions for its virulence and also contribute to the proliferation of nutrient uptake from the environment. We previously elucidated the role of a variety of proteins associated with phagocytosis and trogocytosis, including Rab small GTPases, Rab effectors, including retromer, phosphoinositide-binding proteins, lysosomal hydrolase receptors, protein kinases, and cytoskeletal proteins. However, a number of proteins involved in phagocytosis and trogocytosis remain to be identified, and mechanistic details of their involvement must be elucidated at the molecular level. To date, a number of studies in which a repertoire of proteins associated with phagosomes and potentially involved in phagocytosis have been conducted. In this review, we revisited all phagosome proteome studies we previously conducted in order to reiterate information on the proteome of phagosomes. We demonstrated the core set of constitutive phagosomal proteins and also the set of phagosomal proteins recruited only transiently or in condition-dependent fashions. The catalogs of phagosome proteomes resulting from such analyses can be a useful source of information for future mechanistic studies as well as for confirming or excluding a possibility of whether a protein of interest in various investigations is likely or is potentially involved in phagocytosis and phagosome biogenesis.
Collapse
Affiliation(s)
- Natsuki Watanabe
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo 113-0033, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
- Correspondence: ; Tel.: +81-3-5841-3526
| |
Collapse
|
2
|
Bañuelos C, Betanzos A, Javier-Reyna R, Galindo A, Orozco E. Molecular interplays of the Entamoeba histolytica endosomal sorting complexes required for transport during phagocytosis. Front Cell Infect Microbiol 2022; 12:855797. [DOI: 10.3389/fcimb.2022.855797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 10/06/2022] [Indexed: 11/13/2022] Open
Abstract
Entamoeba histolytica, the causative agent of human amoebiasis, exhibits a continuous membrane remodelling to exert its virulence properties. During this dynamic process, the Endosomal Sorting Complexes Required for Transport (ESCRT) machinery is a key player, particularly in phagocytosis, a virulence hallmark of this parasite. In addition to ESCRT, other molecules contribute to membrane remodelling, including the EhADH adhesin, EhRabs, actin, and the lysobisphosphatidic acid (LBPA). The endocytosis of a prey or molecules induces membrane invaginations, resulting in endosome and multivesicular bodies (MVBs) formation for cargo delivery into lysosomes. Alternatively, some proteins are recycled or secreted. Most of these pathways have been broadly characterized in other biological systems, but poorly described in protozoan parasites. Here, we encompass 10 years of ESCRT research in E. histolytica, highlighting the role of the ESCRT-I and ESCRT-III components and the EhADH and EhVps4-ATPase accessory proteins during phagocytosis. In particular, EhADH exhibits a multifunctional role along the endocytic pathway, from cargo recognition to endosome maturation and lysosomal degradation. Interestingly, the interaction of EhADH with EhVps32 seems to shape a concurrent route to the conventional one for MVBs biogenesis, that could optimize their formation. Furthermore, this adhesin is secreted, but its role in this event remains under study. Other components from the endosomal pathway, such as EhVps23 and LBPA, are also secreted. A proteomic approach performed here, using an anti-LBPA antibody, revealed that some proteins related to membrane trafficking, cellular transport, cytoskeleton dynamics, and transcriptional and translational functions are secreted and associated to LBPA. Altogether, the accumulated knowledge around the ESCRT machinery in E. histolytica, points it out as a dynamic platform facilitating the interaction of molecules participating in different cellular events. Seen as an integrated system, ESCRTs lead to a better understanding of E. histolytica phagocytosis.
Collapse
|
3
|
Nakada-Tsukui K, Watanabe N, Shibata K, Wahyuni R, Miyamoto E, Nozaki T. Proteomic analysis of Atg8-dependent recruitment of phagosomal proteins in the enteric protozoan parasite Entamoeba histolytica. Front Cell Infect Microbiol 2022; 12:961645. [PMID: 36262186 PMCID: PMC9575557 DOI: 10.3389/fcimb.2022.961645] [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: 06/05/2022] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
Autophagy is one of the bulk degradation systems and is conserved throughout eukaryotes. In the enteric protozoan parasite Entamoeba histolytica, the causative agent of human amebiasis, Atg8 is not exclusively involved in autophagy per se but also in other membrane traffic-related pathways such as phagosome biogenesis. We previously reported that repression of atg8 gene expression by antisense small RNA-mediated transcriptional gene silencing (gs) resulted in growth retardation, delayed endocytosis, and reduced acidification of endosomes and phagosomes. In this study, to better understand the role of Atg8 in phagocytosis and trogocytosis, we conducted a comparative proteomic analysis of phagosomes isolated from wild type and atg8-gs strains. We found that 127 and 107 proteins were detected >1.5-fold less or more abundantly, respectively, in phagosomes isolated from the atg8-gs strain, compared to the control strain. Among 127 proteins whose abundance was reduced in phagosomes from atg8-gs, a panel of proteins related to fatty acid metabolism, phagocytosis, and endoplasmic reticulum (ER) homeostasis was identified. Various lysosomal hydrolases and their receptors also tend to be excluded from phagosomes by atg8-gs, reinforcing the notion that Atg8 is involved in phagosomal acidification and digestion. On the contrary, among 107 proteins whose abundance increased in phagosomes from atg8-gs strain, ribosome-related proteins and metabolite interconversion enzymes are enriched. We further investigated the localization of several representative proteins, including adenylyl cyclase-associated protein and plasma membrane calcium pump, both of which were demonstrated to be recruited to phagosomes and trogosomes via an Atg8-dependent mechanism. Taken together, our study has provided the basis of the phagosome proteome to further elucidate molecular events in the Atg8-dependent regulatory network of phagosome/trogosome biogenesis in E. histolytica.
Collapse
Affiliation(s)
- Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
- *Correspondence: Kumiko Nakada-Tsukui, ; Tomoyoshi Nozaki,
| | - Natsuki Watanabe
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kumiko Shibata
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ratna Wahyuni
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Eri Miyamoto
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- *Correspondence: Kumiko Nakada-Tsukui, ; Tomoyoshi Nozaki,
| |
Collapse
|
4
|
Bremer N, Tria FDK, Skejo J, Garg SG, Martin WF. Ancestral state reconstructions trace mitochondria but not phagocytosis to the last eukaryotic common ancestor. Genome Biol Evol 2022; 14:6596370. [PMID: 35642316 PMCID: PMC9185374 DOI: 10.1093/gbe/evac079] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 11/13/2022] Open
Abstract
Two main theories have been put forward to explain the origin of mitochondria in eukaryotes: phagotrophic engulfment (undigested food) and microbial symbiosis (physiological interactions). The two theories generate mutually exclusive predictions about the order in which mitochondria and phagocytosis arose. To discriminate the alternatives, we have employed ancestral state reconstructions (ASR) for phagocytosis as a trait, phagotrophy as a feeding habit, the presence of mitochondria, the presence of plastids, and the multinucleated organization across major eukaryotic lineages. To mitigate the bias introduced by assuming a particular eukaryotic phylogeny, we reconstructed the appearance of these traits across 1789 different rooted gene trees, each having species from opisthokonts, mycetozoa, hacrobia, excavate, archeplastida, and Stramenopiles, Alveolates and Rhizaria. The trees reflect conflicting relationships and different positions of the root. We employed a novel phylogenomic test that summarizes ASR across trees which reconstructs a last eukaryotic common ancestor that possessed mitochondria, was multinucleated, lacked plastids, and was non-phagotrophic as well as non-phagocytic. This indicates that both phagocytosis and phagotrophy arose subsequent to the origin of mitochondria, consistent with findings from comparative physiology. Furthermore, our ASRs uncovered multiple origins of phagocytosis and of phagotrophy across eukaryotes, indicating that, like wings in animals, these traits are useful but neither ancestral nor homologous across groups. The data indicate that mitochondria preceded the origin of phagocytosis, such that phagocytosis cannot have been the mechanism by which mitochondria were acquired.
Collapse
Affiliation(s)
- Nico Bremer
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Fernando D K Tria
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Josip Skejo
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Sriram G Garg
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - William F Martin
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| |
Collapse
|
5
|
CynthiaVanegas-Villa S, Milena Torres-Cifuentes D, Baylon-Pacheco L, Espíritu-Gordillo P, Durán-Díaz Á, Luis Rosales-Encina J, Omaña-Molina M. External pH Variations Modify Proliferation, Erythrophagocytosis, Cytoskeleton Remodeling, and Cell Morphology of Entamoeba histolytica Trophozoites. Protist 2022; 173:125857. [DOI: 10.1016/j.protis.2022.125857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 10/19/2022]
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Chulanetra M, Chaicumpa W. Revisiting the Mechanisms of Immune Evasion Employed by Human Parasites. Front Cell Infect Microbiol 2021; 11:702125. [PMID: 34395313 PMCID: PMC8358743 DOI: 10.3389/fcimb.2021.702125] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/25/2021] [Indexed: 12/14/2022] Open
Abstract
For the establishment of a successful infection, i.e., long-term parasitism and a complete life cycle, parasites use various diverse mechanisms and factors, which they may be inherently bestowed with, or may acquire from the natural vector biting the host at the infection prelude, or may take over from the infecting host, to outmaneuver, evade, overcome, and/or suppress the host immunity, both innately and adaptively. This narrative review summarizes the up-to-date strategies exploited by a number of representative human parasites (protozoa and helminths) to counteract the target host immune defense. The revisited information should be useful for designing diagnostics and therapeutics as well as vaccines against the respective parasitic infections.
Collapse
Affiliation(s)
- Monrat Chulanetra
- Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Wanpen Chaicumpa
- Center of Research Excellence on Therapeutic Proteins and Antibody Engineering, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| |
Collapse
|
8
|
Saito-Nakano Y, Wahyuni R, Nakada-Tsukui K, Tomii K, Nozaki T. Rab7D small GTPase is involved in phago-, trogocytosis and cytoskeletal reorganization in the enteric protozoan Entamoeba histolytica. Cell Microbiol 2020; 23:e13267. [PMID: 32975360 PMCID: PMC7757265 DOI: 10.1111/cmi.13267] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/21/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022]
Abstract
Rab small GTPases regulate membrane traffic between distinct cellular compartments of all eukaryotes in a tempo‐spatially specific fashion. Rab small GTPases are also involved in the regulation of cytoskeleton and signalling. Membrane traffic and cytoskeletal regulation play pivotal role in the pathogenesis of Entamoeba histolytica, which is a protozoan parasite responsible for human amebiasis. E. histolytica is unique in that its genome encodes over 100 Rab proteins, containing multiple isotypes of conserved members (e.g., Rab7) and Entamoeba‐specific subgroups (e.g., RabA, B, and X). Among them, E. histolytica Rab7 is the most diversified group consisting of nine isotypes. While it was previously demonstrated that EhRab7A and EhRab7B are involved in lysosome and phagosome biogenesis, the individual roles of other Rab7 members and their coordination remain elusive. In this study, we characterised the third member of Rab7, Rab7D, to better understand the significance of the multiplicity of Rab7 isotypes in E. histolytica. Overexpression of EhRab7D caused reduction in phagocytosis of erythrocytes, trogocytosis (meaning nibbling or chewing of a portion) of live mammalian cells, and phagosome acidification and maturation. Conversely, transcriptional gene silencing of EhRab7D gene caused opposite phenotypes in phago/trogocytosis and phagosome maturation. Furthermore, EhRab7D gene silencing caused reduction in the attachment to and the motility on the collagen‐coated surface. Image analysis showed that EhRab7D was occasionally associated with lysosomes and prephagosomal vacuoles, but not with mature phagosomes and trogosomes. Finally, in silico prediction of structural organisation of EhRab7 isotypes identified unique amino acid changes on the effector binding surface of EhRab7D. Taken together, our data suggest that EhRab7D plays coordinated counteracting roles: a inhibitory role in phago/trogocytosis and lyso/phago/trogosome biogenesis, and an stimulatory role in adherence and motility, presumably via interaction with unique effectors. Finally, we propose the model in which three EhRab7 isotypes are sequentially involved in phago/trogocytosis.
Collapse
Affiliation(s)
- Yumiko Saito-Nakano
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Ratna Wahyuni
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.,Institute of Tropical Disease, Universitas Airlangga, Surabaya, Indonesia.,Department of Health, Faculty of Vocational Studies, Universitas Airlangga, Surabaya, Indonesia
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kentaro Tomii
- Artificial Intelligence Research Center (AIRC) and Real World Big-Data Computation Open Innovation Laboratory (RWBC-OIL), National Institute of Advance Industrial Science and Technology (AIST), Tokyo, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
9
|
Stryiński R, Łopieńska-Biernat E, Carrera M. Proteomic Insights into the Biology of the Most Important Foodborne Parasites in Europe. Foods 2020; 9:E1403. [PMID: 33022912 PMCID: PMC7601233 DOI: 10.3390/foods9101403] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/24/2020] [Accepted: 09/27/2020] [Indexed: 02/07/2023] Open
Abstract
Foodborne parasitoses compared with bacterial and viral-caused diseases seem to be neglected, and their unrecognition is a serious issue. Parasitic diseases transmitted by food are currently becoming more common. Constantly changing eating habits, new culinary trends, and easier access to food make foodborne parasites' transmission effortless, and the increase in the diagnosis of foodborne parasitic diseases in noted worldwide. This work presents the applications of numerous proteomic methods into the studies on foodborne parasites and their possible use in targeted diagnostics. Potential directions for the future are also provided.
Collapse
Affiliation(s)
- Robert Stryiński
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland;
| | - Elżbieta Łopieńska-Biernat
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland;
| | - Mónica Carrera
- Department of Food Technology, Marine Research Institute (IIM), Spanish National Research Council (CSIC), 36-208 Vigo, Spain
| |
Collapse
|
10
|
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.
Collapse
|
11
|
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.
Collapse
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.
| |
Collapse
|
12
|
Abstract
Calcium signaling plays a key role in many essential processes in almost all eukaryotic systems. It is believed that it may also be an important signaling system of the protist parasite Entamoeba histolytica. Motility, adhesion, cytolysis, and phagocytosis/trogocytosis are important steps in invasion and pathogenesis of E. histolytica, and Ca2+ signaling is thought to be associated with these processes leading to tissue invasion. There are a large number of Ca2+-binding proteins (CaBPs) in E. histolytica, and a number of these proteins appear to be associated with different steps in pathogenesis. The genome encodes 27 EF-hand–containing CaBPs in addition to a number of other Ca2+-binding domain/motif-containing proteins, which suggest intricate calcium signaling network in this parasite. Unlike other eukaryotes, a typical calmodulin-like protein has not been seen in E. histolytica. Though none of the CaBPs display sequence similarity with a typical calmodulin, extensive structural similarity has been seen in spite of lack of significant functional overlap with that of typical calmodulins. One of the unique features observed in E. histolytica is the identification of CaBPs (EhCaBP1, EhCaBP3) that have the ability to directly bind actin and modulate actin dynamics. Direct interaction of CaBPs with actin has not been seen in any other system. Pseudopod formation and phagocytosis are some of the processes that require actin dynamics, and some of the amoebic CaBPs (EhC2Pk, EhCaBP1, EhCaBP3, EhCaBP5) participate in this process. None of these E. histolytica CaBPs have any homolog in organisms other than different species of Entamoeba, suggesting a novel Ca2+ signaling pathway that has evolved in this genus.
Collapse
Affiliation(s)
- Mrigya Babuta
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Alok Bhattacharya
- Department of Biology, Ashoka University, Sonepat, Haryana, India
- * E-mail:
| |
Collapse
|
13
|
Watanabe N, Nakada-Tsukui K, Nozaki T. Two isotypes of phosphatidylinositol 3-phosphate-binding sorting nexins play distinct roles in trogocytosis in Entamoeba histolytica. Cell Microbiol 2019; 22:e13144. [PMID: 31713312 PMCID: PMC7027479 DOI: 10.1111/cmi.13144] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/23/2019] [Accepted: 11/07/2019] [Indexed: 12/27/2022]
Abstract
Phosphatidylinositol phosphates (PIPs) function as important second messengers in many cellular events. In the human intestinal protist Entamoeba histolytica, where phagocytosis/trogocytosis plays an indispensable role in proliferation and pathophysiology during infection, various PIPs are involved in multiple steps of phago/trogocytosis. PI3‐phosphate (PI3P) plays a pivotal role in the biogenesis of phagosome/trogosomes via recruitment of PI3P effectors. Because no known PI3P downstream effectors are conserved in E. histolytica, we exploited a unique method to identify the proteins PI3P dependently recruited to phagosomes. We rationalised that overexpression of PI3P‐binding GFP‐HrsFYVE competes for PI3P on phagosomal membranes and results in dissociation of PI3P effectors from phagosomes. EhVps26 and EhVps35, but not sorting nexins (SNXs), of the retromer complex were detected from phagosomes only without GFP‐HrsFYVE overexpression. Two potential SNXs, EhSNX1 and EhSNX2, identified in the genome, possess only phox homology domain and specifically bound to PI3P, but retromer components, EhVps26 and EhVps35, did not bind to PI3P. Live and immunofluorescence imaging showed that EhSNX1 was recruited to the trogocytic cup and tunnel‐like structures, and subsequently, EhSNX2 was recruited to trogosomes. Furthermore, EhSNX1, but not EhSNX2, specifically bound to Arp2/3 and EhVps26, which were localised to the tunnel‐like structures and the trogosomes, respectively. EhSNX2 gene silencing increased trogocytosis, suggesting that EhSNX2 plays an inhibitory role in trogocytosis.
Collapse
Affiliation(s)
- Natsuki Watanabe
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.,Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
14
|
Assaying How Phagocytic Success Depends on the Elasticity of a Large Target Structure. Biophys J 2019; 117:1496-1507. [PMID: 31586520 DOI: 10.1016/j.bpj.2019.08.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 08/14/2019] [Accepted: 08/26/2019] [Indexed: 01/26/2023] Open
Abstract
Biofilm infections can consist of bacterial aggregates that are an order of magnitude larger than neutrophils, phagocytic immune cells that densely surround aggregates but do not enter them. Because a neutrophil is too small to engulf the entire aggregate, it must be able to detach and engulf a few bacteria at a time if it is to use phagocytosis to clear the infection. Current research techniques do not provide a method for determining how the success of phagocytosis, here defined as the complete engulfment of a piece of foreign material, depends on the mechanical properties of a larger object from which the piece must be removed before being engulfed. This article presents a step toward such a method. By varying polymer concentration or cross-linking density, the elastic moduli of centimeter-sized gels are varied over the range that was previously measured for Pseudomonas aeruginosa biofilms grown from clinical bacterial isolates. Human neutrophils are isolated from blood freshly drawn from healthy adult volunteers, exposed to gel containing embedded beads for 1 h, and removed from the gel. The percentage of collected neutrophils that contain beads that had previously been within the gels is used to measure successful phagocytic engulfment. Both increased polymer concentration in agarose gels and increased cross-linking density in alginate gels are associated with a decreased success of phagocytic engulfment. Upon plotting the percentage of neutrophils showing successful engulfment as a function of the elastic modulus of the gel to which they were applied, it is found that data from both alginate and agarose gels collapse onto the same curve. This suggests that gel mechanics may be impacting the success of phagocytosis and demonstrates that this experiment is a step toward realizing methods for measuring how the mechanics of a large target, or a large structure in which smaller targets are embedded, impact the success of phagocytic engulfment.
Collapse
|
15
|
Betanzos A, Bañuelos C, Orozco E. Host Invasion by Pathogenic Amoebae: Epithelial Disruption by Parasite Proteins. Genes (Basel) 2019; 10:E618. [PMID: 31416298 PMCID: PMC6723116 DOI: 10.3390/genes10080618] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/25/2019] [Accepted: 04/29/2019] [Indexed: 02/07/2023] Open
Abstract
The epithelium represents the first and most extensive line of defence against pathogens, toxins and pollutant agents in humans. In general, pathogens have developed strategies to overcome this barrier and use it as an entrance to the organism. Entamoeba histolytica, Naegleriafowleri and Acanthamoeba spp. are amoebae mainly responsible for intestinal dysentery, meningoencephalitis and keratitis, respectively. These amoebae cause significant morbidity and mortality rates. Thus, the identification, characterization and validation of molecules participating in host-parasite interactions can provide attractive targets to timely intervene disease progress. In this work, we present a compendium of the parasite adhesins, lectins, proteases, hydrolases, kinases, and others, that participate in key pathogenic events. Special focus is made for the analysis of assorted molecules and mechanisms involved in the interaction of the parasites with epithelial surface receptors, changes in epithelial junctional markers, implications on the barrier function, among others. This review allows the assessment of initial host-pathogen interaction, to correlate it to the potential of parasite invasion.
Collapse
Affiliation(s)
- Abigail Betanzos
- Consejo Nacional de Ciencia y Tecnología (CONACYT), Mexico City 03940, Mexico
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Mexico City 07360, Mexico
| | - Cecilia Bañuelos
- Coordinación General de Programas de Posgrado Multidisciplinarios, Programa de Doctorado Transdisciplinario en Desarrollo Científico y Tecnológico para la Sociedad, CINVESTAV-IPN, Mexico City 07360, Mexico
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV-IPN, Mexico City 07360, Mexico.
| |
Collapse
|
16
|
Sharma S, Agarwal S, Bharadwaj R, Somlata, Bhattacharya S, Bhattacharya A. Novel regulatory roles of PtdIns(4,5)P2generating enzyme EhPIPKI in actin dynamics and phagocytosis ofEntamoeba histolytica. Cell Microbiol 2019; 21:e13087. [DOI: 10.1111/cmi.13087] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 07/03/2019] [Indexed: 02/06/2023]
Affiliation(s)
- Shalini Sharma
- School of Life SciencesJawaharlal Nehru University New Delhi India
| | - Shalini Agarwal
- School of Life SciencesJawaharlal Nehru University New Delhi India
| | - Ravi Bharadwaj
- School of MedicineUMASS Medical School Worcester Massachusetts USA
| | - Somlata
- Multidisciplinary Centre for Advance Research and StudiesJamia Milia Islamia New Delhi India
| | - Sudha Bhattacharya
- School of Environmental SciencesJawaharlal Nehru University New Delhi India
| | | |
Collapse
|
17
|
Javier-Reyna R, Montaño S, García-Rivera G, Rodríguez MA, González-Robles A, Orozco E. EhRabB mobilises the EhCPADH complex through the actin cytoskeleton during phagocytosis of Entamoeba histolytica. Cell Microbiol 2019; 21:e13071. [PMID: 31219662 DOI: 10.1111/cmi.13071] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/15/2019] [Accepted: 06/11/2019] [Indexed: 12/30/2022]
Abstract
Movement and phagocytosis are clue events in colonisation and invasion of tissues by Entamoeba histolytica, the protozoan causative of human amoebiasis. During phagocytosis, EhRab proteins interact with other functional molecules, conducting them to the precise cellular site. The gene encoding EhrabB is located in the complementary chain of the DNA fragment containing Ehcp112 and Ehadh genes, which encode for the proteins of the EhCPADH complex, involved in phagocytosis. This particular genetic organisation suggests that the three corresponding proteins may be functionally related. Here, we studied the relationship of EhRabB with EhCPADH and actin during phagocytosis. First, we obtained the EhRabB 3D structure to carry out docking analysis to predict the interaction sites involved in the EhRabB protein and the EhCPADH complex contact. By confocal microscopy, transmission electron microscopy, and immunoprecipitation assays, we revealed the interaction among these proteins when they move through different vesicles formed during phagocytosis. The role of the actin cytoskeleton in this event was also confirmed using Latrunculin A to interfere with actin polymerisation. This affected the movement of EhRabB and EhCPADH, as well as the rate of phagocytosis. Mutant trophozoites, silenced in EhrabB gene, evidenced the interaction of this molecule with EhCPADH and strengthened the role of actin during erythrophagocytosis.
Collapse
Affiliation(s)
- Rosario Javier-Reyna
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV-IPN, Mexico City, Mexico
| | - Sarita Montaño
- Laboratorio de Bioinformática, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Sinaloa (FCQB-UAS), Culiacán, Sinaloa, México
| | | | | | | | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV-IPN, Mexico City, Mexico
| |
Collapse
|
18
|
Sharma S, Bhattacharya S, Bhattacharya A. PtdIns(4,5)P 2 is generated by a novel phosphatidylinositol 4-phosphate 5-kinase in the protist parasite Entamoeba histolytica. FEBS J 2019; 286:2216-2234. [PMID: 30843363 DOI: 10.1111/febs.14804] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 02/03/2019] [Accepted: 03/05/2019] [Indexed: 01/02/2023]
Abstract
Entamoeba histolytica is an intestinal protist parasite that causes amoebiasis, a major source of morbidity and mortality in developing countries. Phosphoinositides are involved in signalling systems that have a role in invasion and pathogenesis of this parasite. Phosphatidylinositol 4-phosphate 5-kinase (PIP5K) catalyses the generation of phosphatidylinositol(4,5)bisphosphate (PtdIns(4,5)P2 ), a key species of phosphoinositide that regulates various cellular processes. However, phosphatidylinositol phosphate kinase (PIPK) family of enzymes have not been characterized in E. histolytica. Here, we report the identification and characterization of type I PIPK (EhPIPKI) of E. histolytica. Computational analysis revealed homologs of type I and III PIPK family in E. histolytica and the absence of type II PIPK. In spite of low overall sequence identity, the kinase domain was found to be highly conserved. Interestingly, a unique insertion of a tandem repeat motif was observed in EhPIPKI distinguishing it from existing PIPKs of other organisms. Substrate profiling showed that EhPIPKI could phosphorylate at third and fifth hydroxyl positions of phosphatidylinositols, though the predominant substrate was phosphatidylinositol 4-phosphate (PtdIns(4)P). Furthermore, EhPIPKI underwent intracellular cleavage close to the amino-terminal, generating two distinct fragments Nter-EhPIPKI (27p) and Cter-EhPIPKI (47p). Immunofluorescence and cellular fractionation revealed that the full-length EhPIPKI and the Cter-EhPIPKI containing carboxyl-terminal activation loop were present in the plasma membrane while the Nter-EhPIPKI was observed in the cytosolic region. In conclusion, E. histolytica has a single EhPIPKI gene that displays novel properties of post-translational processing, the presence of a repeat domain and substrate specificity not observed in any PIPK enzyme so far.
Collapse
Affiliation(s)
- Shalini Sharma
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
19
|
EhFP10: A FYVE family GEF interacts with myosin IB to regulate cytoskeletal dynamics during endocytosis in Entamoeba histolytica. PLoS Pathog 2019; 15:e1007573. [PMID: 30779788 PMCID: PMC6396940 DOI: 10.1371/journal.ppat.1007573] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/01/2019] [Accepted: 01/08/2019] [Indexed: 01/07/2023] Open
Abstract
Motility and phagocytosis are key processes that are involved in invasive amoebiasis disease caused by intestinal parasite Entamoeba histolytica. Previous studies have reported unconventional myosins to play significant role in membrane based motility as well as endocytic processes. EhMyosin IB is the only unconventional myosin present in E. histolytica, is thought to be involved in both of these processes. Here, we report an interaction between the SH3 domain of EhMyosin IB and c-terminal domain of EhFP10, a Rho guanine nucleotide exchange factor. EhFP10 was found to be confined to Entamoeba species only, and to contain a c-terminal domain that binds and bundles actin filaments. EhFP10 was observed to localize in the membrane ruffles, phagocytic and macropinocytic cups of E. histolytica trophozoites. It was also found in early pinosomes but not early phagosomes. A crystal structure of the c-terminal SH3 domain of EhMyosin IB (EhMySH3) in complex with an EhFP10 peptide and co-localization studies established the interaction of EhMySH3 with EhFP10. This interaction was shown to lead to inhibition of actin bundling activity and to thereby regulate actin dynamics during endocytosis. We hypothesize that unique domain architecture of EhFP10 might be compensating the absence of Wasp and related proteins in Entamoeba, which are known partners of myosin SH3 domains in other eukaryotes. Our findings also highlights the role of actin bundling during endocytosis.
Collapse
|
20
|
Hernández‐Cuevas NA, Jhingan GD, Petropolis D, Vargas M, Guillen N. Acetylation is the most abundant actin modification in
Entamoeba histolytica
and modifications of actin's amino‐terminal domain change cytoskeleton activities. Cell Microbiol 2018; 21:e12983. [DOI: 10.1111/cmi.12983] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 09/27/2018] [Accepted: 10/30/2018] [Indexed: 12/16/2022]
Affiliation(s)
| | | | - Debora Petropolis
- Institut Pasteur Unité Biologie Cellulaire du Parasitisme Paris France
- INSERM Unit 786 Paris France
| | - Miguel Vargas
- Departamento de Biomedicina Molecular Instituto Politécnico Nacional, Centro de Investigación y de Estudios Avanzados CINVESTAV Mexico City Mexico
| | - Nancy Guillen
- Institut Pasteur Unité Biologie Cellulaire du Parasitisme Paris France
- INSERM Unit 786 Paris France
- Centre National de la Recherche Scientifique, ERL9195 Paris France
| |
Collapse
|
21
|
Verma K, Srivastava VK, Datta S. Rab GTPases take centre stage in understanding Entamoeba histolytica biology. Small GTPases 2018; 11:320-333. [PMID: 30273093 DOI: 10.1080/21541248.2018.1528840] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Rab GTPases constitute the largest subgroup in the Ras superfamily of GTPases. It is well established that different Rab GTPases are localized in discrete subcellular localization and regulate the membrane trafficking in nearly all eukaryotic cells. Rab GTPase diversity is often regarded as an expression of vesicular trafficking complexity. The pathogenic amoeba Entamoeba histolytica harbours 91 Rab GTPases which is the highest among the currently available genome sequences from the eukaryotic kingdom. Here, we review the current status of amoebic Rab GTPases diversity, unique biochemical and structural features and summarise their predicted regulators. We discuss how amoebic Rab GTPases are involved in cellular processes such as endocytosis, phagocytosis, and invasion of host cellular components, which are essential for parasite survival and virulence.
Collapse
Affiliation(s)
- Kuldeep Verma
- Institute of Science, Nirma University , Ahmedabad, Gujarat, India.,Regional Centre for Biotechnology, NCR Biotech Science Cluster , Faridabad, India
| | | | - Sunando Datta
- Department of Biological Science, Indian Institute of Science Education and Research Bhopal , Bhauri, India
| |
Collapse
|
22
|
Manich M, Hernandez-Cuevas N, Ospina-Villa JD, Syan S, Marchat LA, Olivo-Marin JC, Guillén N. Morphodynamics of the Actin-Rich Cytoskeleton in Entamoeba histolytica. Front Cell Infect Microbiol 2018; 8:179. [PMID: 29896453 PMCID: PMC5986921 DOI: 10.3389/fcimb.2018.00179] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/09/2018] [Indexed: 02/01/2023] Open
Abstract
Entamoeba histolytica is the anaerobic protozoan parasite responsible for human amoebiasis, the third most deadly parasitic disease worldwide. This highly motile eukaryotic cell invades human tissues and constitutes an excellent experimental model of cell motility and cell shape deformation. The absence of extranuclear microtubules in Entamoeba histolytica means that the actin-rich cytoskeleton takes on a crucial role in not only amoebic motility but also other processes sustaining pathogenesis, such as the phagocytosis of human cells and the parasite's resistance of host immune responses. Actin is highly conserved among eukaryotes, although diverse isoforms exist in almost all organisms studied to date. However, E. histolytica has a single actin protein, the structure of which differs significantly from those of its human homologs. Here, we studied the expression, structure and dynamics of actin in E. histolytica. We used molecular and cellular approaches to evaluate actin gene expression during intestinal invasion by E. histolytica trophozoites. Based on a three-dimensional structural bioinformatics analysis, we characterized protein domains differences between amoebic actin and human actin. Fine-tuned molecular dynamics simulations enabled us to examine protein motion and refine the three-dimensional structures of both actins, including elements potentially accounting for differences changes in the affinity properties of amoebic actin and deoxyribonuclease I. The dynamic, multifunctional nature of the amoebic cytoskeleton prompted us to examine the pleiotropic forms of actin structures within live E. histolytica cells; we observed the cortical cytoskeleton, stress fibers, "dot-like" structures, adhesion plates, and macropinosomes. In line with these data, a proteomics study of actin-binding proteins highlighted the Arp2/3 protein complex as a crucial element for the development of macropinosomes and adhesion plaques.
Collapse
Affiliation(s)
- Maria Manich
- BioImaging Unit, Institut Pasteur, Paris, France.,Cell Biology of Parasitism Unit, Institut Pasteur, Paris, France
| | | | - Juan D Ospina-Villa
- Instituto Politécnico Nacional, Escuela Nacional de Medicina y Homeopatía, Mexico City, Mexico
| | - Sylvie Syan
- Cell Biology of Parasitism Unit, Institut Pasteur, Paris, France
| | - Laurence A Marchat
- Instituto Politécnico Nacional, Escuela Nacional de Medicina y Homeopatía, Mexico City, Mexico
| | | | - Nancy Guillén
- Cell Biology of Parasitism Unit, Institut Pasteur, Paris, France.,Centre National de la Recherche Scientifique, CNRS-ERL9195, Paris, France
| |
Collapse
|
23
|
Bharadwaj R, Sharma S, Arya R, Bhattacharya S, Bhattacharya A. EhRho1 regulates phagocytosis by modulating actin dynamics through EhFormin1 and EhProfilin1 inEntamoeba histolytica. Cell Microbiol 2018; 20:e12851. [DOI: 10.1111/cmi.12851] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 03/12/2018] [Accepted: 03/25/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Ravi Bharadwaj
- School of Life Sciences; Jawaharlal Nehru University; New Delhi India
| | - Shalini Sharma
- School of Life Sciences; Jawaharlal Nehru University; New Delhi India
| | - Ranjana Arya
- School of Biotechnology; Jawaharlal Nehru University; New Delhi India
| | - Sudha Bhattacharya
- School of Environmental Sciences; Jawaharlal Nehru University; New Delhi India
| | - Alok Bhattacharya
- School of Life Sciences; Jawaharlal Nehru University; New Delhi India
| | | |
Collapse
|
24
|
Somlata, Nakada-Tsukui K, Nozaki T. AGC family kinase 1 participates in trogocytosis but not in phagocytosis in Entamoeba histolytica. Nat Commun 2017; 8:101. [PMID: 28740237 PMCID: PMC5524646 DOI: 10.1038/s41467-017-00199-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 06/08/2017] [Indexed: 02/07/2023] Open
Abstract
The protozoan parasite Entamoeba histolytica is the aetiologic agent of amoebiasis, an endemic infection in developing countries with considerable morbidity and mortality. Recently, trogocytosis has been recognized as the key step in amoebic cytolysis and invasion, a paradigm shift in understanding pathogenicity of this organism. Here we report that AGC family kinase 1 is specifically involved in trogocytosis of live human cells and does not participate in phagocytosis of dead cells. Live imaging reveals localization of this kinase in the long and thin tunnels formed during trogocytosis but not in the trogosomes (endosomes formed after trogocytosis). Silencing of the specific gene leads to a defect in CHO cell destruction and trogocytosis while other endocytic processes remain unaffected. The results suggest that the trogocytic pathway is likely to be different from phagocytosis though many of the steps and molecules involved may be common. Entamoeba histolytica can kill host cells by trogocytosis, while it ingests dead cells by phagocytosis. Here, Somlata et al. show that EhAGCK1, an AGC family kinase, is specifically involved in trogocytosis, shedding light on the molecular differences between trogocytosis and phagocytosis.
Collapse
Affiliation(s)
- Somlata
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Tomoyoshi Nozaki
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan. .,Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-572, Japan. .,Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Tokyo, 113-0033, Japan.
| |
Collapse
|
25
|
Verma K, Datta S. The Monomeric GTPase Rab35 Regulates Phagocytic Cup Formation and Phagosomal Maturation in Entamoeba histolytica. J Biol Chem 2017; 292:4960-4975. [PMID: 28126902 DOI: 10.1074/jbc.m117.775007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 01/25/2017] [Indexed: 12/27/2022] Open
Abstract
One of the hallmarks of amoebic colitis is the detection of Entamoeba histolytica (Eh) trophozoites with ingested erythrocytes. Therefore, erythrophagocytosis is traditionally considered as one of the most important criteria to identify the pathogenic behavior of the amoebic trophozoites. Phagocytosis is an essential process for the proliferation and virulence of this parasite. Phagocytic cargo, upon internalization, follows a defined trafficking route to amoebic lysosomal degradation machinery. Here, we demonstrated the role of EhRab35 in the early and late phases of erythrophagocytosis by the amoeba. EhRab35 showed large vacuolar as well as punctate vesicular localization. The spatiotemporal dynamics of vacuolar EhRab35 and its exchange with soluble cytosolic pool were monitored by fluorescence recovery after photobleaching experiments. Using extensive microscopy and biochemical methods, we demonstrated that upon incubation with RBCs EhRab35 is recruited to the site of phagocytic cups as well as to the nascent phagosomes that harbor Gal/GalNAc lectin and actin. Overexpression of a dominant negative mutant of EhRab35 reduced phagocytic cup formation and thereby reduced RBC internalization, suggesting a potential role of the Rab GTPase in the cup formation. Furthermore, we also performed a phagosomal maturation assay and observed that the activated form of EhRab35 significantly increased the rate of RBC degradation. Interestingly, this mutant also significantly enhanced the number of acidic compartments in the trophozoites. Taken together, our results suggest that EhRab35 is involved in the initial stage of phagocytosis as well as in the phagolysosomal biogenesis in E. histolytica and thus contributes to the pathogenicity of the parasite.
Collapse
Affiliation(s)
- Kuldeep Verma
- From the Department of Biological Science, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri 462030, India
| | - Sunando Datta
- From the Department of Biological Science, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri 462030, India
| |
Collapse
|
26
|
Klinger CM, Ramirez-Macias I, Herman EK, Turkewitz AP, Field MC, Dacks JB. Resolving the homology-function relationship through comparative genomics of membrane-trafficking machinery and parasite cell biology. Mol Biochem Parasitol 2016; 209:88-103. [PMID: 27444378 PMCID: PMC5140719 DOI: 10.1016/j.molbiopara.2016.07.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/12/2016] [Accepted: 07/16/2016] [Indexed: 10/21/2022]
Abstract
With advances in DNA sequencing technology, it is increasingly common and tractable to informatically look for genes of interest in the genomic databases of parasitic organisms and infer cellular states. Assignment of a putative gene function based on homology to functionally characterized genes in other organisms, though powerful, relies on the implicit assumption of functional homology, i.e. that orthology indicates conserved function. Eukaryotes reveal a dazzling array of cellular features and structural organization, suggesting a concomitant diversity in their underlying molecular machinery. Significantly, examples of novel functions for pre-existing or new paralogues are not uncommon. Do these examples undermine the basic assumption of functional homology, especially in parasitic protists, which are often highly derived? Here we examine the extent to which functional homology exists between organisms spanning the eukaryotic lineage. By comparing membrane trafficking proteins between parasitic protists and traditional model organisms, where direct functional evidence is available, we find that function is indeed largely conserved between orthologues, albeit with significant adaptation arising from the unique biological features within each lineage.
Collapse
Affiliation(s)
- Christen M Klinger
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Emily K Herman
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Aaron P Turkewitz
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Mark C Field
- School of Life Sciences, University of Dundee, Dundee, UK
| | - Joel B Dacks
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada.
| |
Collapse
|
27
|
Luna-Nácar M, Navarrete-Perea J, Moguel B, Bobes RJ, Laclette JP, Carrero JC. Proteomic Study of Entamoeba histolytica Trophozoites, Cysts, and Cyst-Like Structures. PLoS One 2016; 11:e0156018. [PMID: 27228164 PMCID: PMC4882050 DOI: 10.1371/journal.pone.0156018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 05/09/2016] [Indexed: 11/23/2022] Open
Abstract
The cyst stage of Entamoeba histolytica is a promising therapeutic target against human amoebiasis. Our research team previously reported the production in vitro of Cyst-Like Structures (CLS) sharing structural features with cysts, including rounded shape, size reduction, multinucleation, and the formation of a chitin wall coupled to the overexpression of glucosamine 6-phosphate isomerase, the rate-limiting enzyme of the chitin synthesis pathway. A proteomic study of E. histolytica trophozoites, cysts, and in vitro-produced CLS is reported herein to determine the nature of CLS, widen our knowledge on the cyst stage, and identify possible proteins and pathways involved in the encystment process. Total protein extracts were obtained from E. histolytica trophozoites, CLS, and partially purified cysts recovered from the feces of amoebic human patients; extracts were trypsin-digested and analyzed by LC-MS/MS. In total, 1029 proteins were identified in trophozoites, 550 in CLS, and 411 in cysts, with 539, 299, and 84 proteins unique to each sample, respectively, and only 74 proteins shared by all three stages. About 70% of CLS proteins were shared with trophozoites, even though differences were observed in the relative protein abundance. While trophozoites showed a greater abundance of proteins associated to a metabolically active cell, CLS showed higher expression of proteins related to proteolysis, redox homeostasis, and stress response. In addition, the expression of genes encoding for the cyst wall proteins Jessie and Jacob was detected by RT-PCR and the Jacob protein identified by Western blotting and immunofluorescence in CLS. However, the proteomic profile of cysts as determined by LC-MS/MS was very dissimilar to that of trophozoites and CLS, with almost 40% of hypothetical proteins. Our global results suggest that CLS are more alike to trophozoites than to cysts, and they could be generated as a rapid survival response of trophozoites to a stressful condition, which allows the parasite to survive temporarily inside a chitin-like resistant cover containing Jacob protein. Our findings lead us to suggest that encystment and CLS formation could be distinct stress responses. In addition, we show that cysts express a high number of genes with unknown function, including four new, highly antigenic, possibly membrane-located proteins that could be targets of therapeutic and diagnostic usefulness.
Collapse
Affiliation(s)
- Milka Luna-Nácar
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - José Navarrete-Perea
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - Bárbara Moguel
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - Raúl J. Bobes
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - Juan P. Laclette
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
| | - Julio C. Carrero
- Department of Immunology, Instituto de Investigaciones Biomédicas, Tercer Circuito Exterior s/n, Ciudad Universitaria, Universidad Nacional Autónoma de México, 04510, México D.F., México
- * E-mail:
| |
Collapse
|
28
|
Alcolea PJ, Alonso A, Degayón MA, Moreno-Paz M, Jiménez M, Molina R, Larraga V. In vitro infectivity and differential gene expression of Leishmania infantum metacyclic promastigotes: negative selection with peanut agglutinin in culture versus isolation from the stomodeal valve of Phlebotomus perniciosus. BMC Genomics 2016; 17:375. [PMID: 27206922 PMCID: PMC4874012 DOI: 10.1186/s12864-016-2672-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 04/26/2016] [Indexed: 11/10/2022] Open
Abstract
Background Leishmania infantum is the protozoan parasite responsible for zoonotic visceral leishmaniasis in the Mediterranean basin. A recent outbreak in humans has been reported in this area. The life cycle of the parasite is digenetic. The promastigote stage develops within the gut of phlebotomine sand flies, whereas amastigotes survive and multiply within phagolysosomes of mammalian host phagocytes. The major vector of L. infantum in Spain is Phlebotomus perniciosus. The axenic culture model of promastigotes is generally used because it is able to mimic the conditions of the natural environment (i.e. the sand fly vector gut). However, infectivity decreases with culture passages and infection of laboratory animals is frequently required. Enrichment of the stationary phase population in highly infective metacyclic promastigotes is achieved by negative selection with peanut agglutinin (PNA), which is possible only in certain Leishmania species such as L. major and L. infantum. In this study, in vitro infectivity and differential gene expression of cultured PNA-negative promastigotes (Pro-PNA−) and metacyclic promastigotes isolated from the sand fly anterior thoracic midgut (Pro-Pper) have been compared. Results In vitro infectivity is about 30 % higher in terms of rate of infected cells and number of amastigotes per infected cell in Pro-Pper than in Pro-PNA−. This finding is in agreement with up-regulation of a leishmanolysin gene (gp63) and genes involved in biosynthesis of glycosylinositolphospholipids (GIPL), lipophosphoglycan (LPG) and proteophosphoglycan (PPG) in Pro-Pper. In addition, differences between Pro-Pper and Pro-PNA− in genes involved in important cellular processes (e.g. signaling and regulation of gene expression) have been found. Conclusions Pro-Pper are significantly more infective than peanut lectin non-agglutinating ones. Therefore, negative selection with PNA is an appropriate method for isolating metacyclic promastigotes in stationary phase of axenic culture but it does not allow reaching the in vitro infectivity levels of Pro-Pper. Indeed, GIPL, LPG and PPG biosynthetic genes together with a gp63 gene are up-regulated in Pro-Pper and interestingly, the correlation coefficient between both transcriptomes in terms of transcript abundance is R2 = 0.68. This means that the correlation is sufficiently high to consider that both samples are physiologically comparable (i.e. the experiment was correctly designed and performed) and sufficiently low to conclude that important differences in transcript abundance have been found. Therefore, the implications of axenic culture should be evaluated case-by-case in each experimental design even when the stationary phase population in culture is enriched in metacyclic promastigotes by negative selection with PNA. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2672-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Pedro J Alcolea
- Laboratorio de Parasitología Molecular, Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), calle Ramiro de Maeztu, 9, 28040, Madrid, Spain.
| | - Ana Alonso
- Laboratorio de Parasitología Molecular, Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), calle Ramiro de Maeztu, 9, 28040, Madrid, Spain
| | - María A Degayón
- Laboratorio de Parasitología Molecular, Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), calle Ramiro de Maeztu, 9, 28040, Madrid, Spain
| | - Mercedes Moreno-Paz
- Laboratorio de Ecología Molecular, Centro de Astrobiología, (Instituto Nacional de Técnica Aeroespacial "Esteban Terradas"-Consejo Superior de Investigaciones Científicas), ctra. de Ajalvir Km 4, 28850, Torrejón de Ardoz, Madrid, Spain
| | - Maribel Jiménez
- Unidad de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Virología e Inmunología Sanitarias (Instituto de Salud Carlos III), ctra. Majadahonda-Pozuelo s/n, 28220, Majadahonda, Madrid, Spain
| | - Ricardo Molina
- Unidad de Entomología Médica, Servicio de Parasitología, Centro Nacional de Microbiología, Virología e Inmunología Sanitarias (Instituto de Salud Carlos III), ctra. Majadahonda-Pozuelo s/n, 28220, Majadahonda, Madrid, Spain
| | - Vicente Larraga
- Laboratorio de Parasitología Molecular, Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), calle Ramiro de Maeztu, 9, 28040, Madrid, Spain
| |
Collapse
|
29
|
López-Ortega O, Ovalle-García E, Ortega-Blake I, Antillón A, Chávez-Munguía B, Patiño-López G, Fragoso-Soriano R, Santos-Argumedo L. Myo1g is an active player in maintaining cell stiffness in B-lymphocytes. Cytoskeleton (Hoboken) 2016; 73:258-68. [DOI: 10.1002/cm.21299] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 04/11/2016] [Accepted: 04/13/2016] [Indexed: 12/11/2022]
Affiliation(s)
- O. López-Ortega
- Departamento De Biomedicina Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
- Facultad De Medicina, Universidad Nacional Autónoma De México; Ciudad De México C. P. 04510 México
| | - E. Ovalle-García
- Universidad Autónoma De Nuevo León, UANL. Facultad De Ingeniería Mecánica Y Eléctrica, Av. Universidad S/N, Ciudad Universitaria, San Nicolás De Los Garza; Nuevo León C. P. 66451 México
| | - I. Ortega-Blake
- Instituto De Ciencias Físicas, UNAM; Cuernavaca Morelos C. P. 62210 México
| | - A. Antillón
- Instituto De Ciencias Físicas, UNAM; Cuernavaca Morelos C. P. 62210 México
| | - B. Chávez-Munguía
- Departamento De Infectómica Y Patogénesis Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
| | - G. Patiño-López
- Laboratorio De Investigación En Inmunología Y Proteómica, Hospital Infantil De México, “Federico Gómez”; Ciudad De México C. P. 06720 México
| | - R. Fragoso-Soriano
- Departamento De Física; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
| | - L. Santos-Argumedo
- Departamento De Biomedicina Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
| |
Collapse
|
30
|
Hanadate Y, Saito-Nakano Y, Nakada-Tsukui K, Nozaki T. Endoplasmic reticulum-resident Rab8A GTPase is involved in phagocytosis in the protozoan parasite Entamoeba histolytica. Cell Microbiol 2016; 18:1358-73. [PMID: 26807810 PMCID: PMC5071775 DOI: 10.1111/cmi.12570] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 12/31/2015] [Accepted: 01/19/2016] [Indexed: 12/20/2022]
Abstract
Phagocytosis is indispensable for the pathogenesis of the intestinal protozoan parasite Entamoeba histolytica. Here, we showed that in E. histolytica Rab8A, which is generally involved in trafficking from the trans‐Golgi network to the plasma membrane in other organisms but was previously identified in phagosomes of the amoeba in the proteomic analysis, primarily resides in the endoplasmic reticulum (ER) and participates in phagocytosis. We demonstrated that down‐regulation of EhRab8A by small antisense RNA‐mediated transcriptional gene silencing remarkably reduced adherence and phagocytosis of erythrocytes, bacteria and carboxylated latex beads. Surface biotinylation followed by SDS‐PAGE analysis revealed that the surface expression of several proteins presumably involved in target recognition was reduced in the EhRab8A gene‐silenced strain. Further, overexpression of wild‐type EhRab8A augmented phagocytosis, whereas expression of the dominant‐negative form of EhRab8A resulted in reduced phagocytosis. These results indicated that EhRab8A regulates transport of surface receptor(s) for the prey from the ER to the plasma membrane. To our knowledge, this is the first report that the ER‐resident Rab GTPase is involved in phagocytosis through the regulation of trafficking of a surface receptor, supporting a premise of direct involvement of the ER in phagocytosis.
Collapse
Affiliation(s)
- Yuki Hanadate
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan
| | - Yumiko Saito-Nakano
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Tomoyoshi Nozaki
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan. .,Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan.
| |
Collapse
|
31
|
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.
Collapse
|
32
|
Babuta M, Mansuri MS, Bhattacharya S, Bhattacharya A. The Entamoeba histolytica, Arp2/3 Complex Is Recruited to Phagocytic Cups through an Atypical Kinase EhAK1. PLoS Pathog 2015; 11:e1005310. [PMID: 26646565 PMCID: PMC4672914 DOI: 10.1371/journal.ppat.1005310] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 11/04/2015] [Indexed: 12/11/2022] Open
Abstract
The parasite Entamoeba histolytica is the etiological agent of amoebiasis and phagocytosis plays a key role in virulence of this organism. Signaling pathways involved in activation of cytoskeletal dynamics required for phagocytosis remain to be elucidated. Phagocytosis is initiated with sequential recruitment of EhC2PK, EhCaBP1, EhCaBP3 and an atypical kinase EhAK1 after particle attachment. Here we show that EhARPC1, an essential subunit of the actin branching complex Arp 2/3 is recruited to the phagocytic initiation sites by EhAK1. Imaging, expression knockdown of different molecules and pull down experiments suggest that EhARPC1 interacts with EhAK1 and that it is required during initiation of phagocytosis and phagosome formation. Moreover, recruitment of EhARPC2 at the phagocytosis initiation by EhAK1 is also observed, indicating that the Arp 2/3 complex is recruited. In conclusion, these results suggests a novel mechanism of recruitment of Arp 2/3 complex during phagocytosis in E. histolytica. E. histolytica is the causative agent of amoebiasis and leads to morbidity and mortality in developing countries. It is known to phagocytose immune and non-immune cells, epithelial tissue, erythrocytes and commensal bacteria. The high rate of phagocytosis in this protist parasite provides a unique system to study the signaling cascade that is activated after attachment of the particle to the cell surface. The major objective of the signaling pathway is to generate force for uptake of the particle and this is done through stimulating cytoskeleton to form appropriate structures. However, the molecular mechanism of the same is still largely unknown in E. histolytica, though this pathway has been characterized in many other systems. We have been investigating this pathway by using red blood cells as a particle and have identified different molecules required during the initial stages of phagocytosis. In this study we demonstrate the mechanism by which actin cytoskeleton branching complex EhARP2/3 is recruited at the site of erythrophagocytosis and show that the recruitment is through an atypical alpha kinase EhAK1. A number of different approaches, such as pull down assay, conditional suppression of EhAK1 expression and imaging were used to decipher this pathway. Therefore this study provides a mechanism by which actin dynamics couples to the initial signaling system, activated on attachment of RBC to the cell receptors.
Collapse
Affiliation(s)
- Mrigya Babuta
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - M Shahid Mansuri
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
- School of Natural Sciences, Department of life Sciences, Shiv Nadar University, Uttar Pradesh, India
- * E-mail: ,
| |
Collapse
|
33
|
Bolaños V, Díaz-Martínez A, Soto J, Marchat LA, Sanchez-Monroy V, Ramírez-Moreno E. Kaempferol inhibits Entamoeba histolytica growth by altering cytoskeletal functions. Mol Biochem Parasitol 2015; 204:16-25. [PMID: 26620675 DOI: 10.1016/j.molbiopara.2015.11.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/30/2015] [Accepted: 11/20/2015] [Indexed: 11/27/2022]
Abstract
The flavonoid kaempferol obtained from Helianthemum glomeratum, an endemic Mexican medicinal herb used to treat gastrointestinal disorders, has been shown to inhibit growth of Entamoeba histolytica trophozoites in vitro; however, the mechanisms associated with this activity have not been documented. Several works reported that kaempferol affects cytoskeleton in mammalian cells. In order to gain insights into the action mechanisms involved in the anti-amoebic effect of kaempferol, here we evaluated the effect of this compound on the pathogenic events driven by the cytoskeleton during E. histolytica infection. We also carried out a two dimensional gel-based proteomic analysis to evidence modulated proteins that could explain the phenotypical changes observed in trophozoites. Our results showed that kaempferol produces a dose-dependent effect on trophozoites growth and viability with optimal concentration being 27.7 μM. Kaempferol also decreased adhesion, it increased migration and phagocytic activity, but it did not affect erythrocyte binding nor cytolytic capacity of E. histolytica. Congruently, proteomic analysis revealed that the cytoskeleton proteins actin, myosin II heavy chain and cortexillin II were up-regulated in response to kaempferol treatment. In conclusion, kaempferol anti-amoebic effects were associated with deregulation of proteins related with cytoskeleton, which altered invasion mechanisms.
Collapse
Affiliation(s)
- Verónica Bolaños
- Doctorado en Ciencias en Biotecnología, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico
| | - Alfredo Díaz-Martínez
- Posgrado en Biomedicina Molecular, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico
| | - Jacqueline Soto
- Posgrado en Biomedicina Molecular, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico; Doctorado en Ciencias en Biotecnología, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico
| | - Laurence A Marchat
- Posgrado en Biomedicina Molecular, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico; Doctorado en Ciencias en Biotecnología, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico
| | - Virginia Sanchez-Monroy
- Laboratorio Multidisciplinario de Investigación, Escuela Militar de Graduados de Sanidad, Universidad del Ejército y Fuerza Aérea, México City 11620, Mexico
| | - Esther Ramírez-Moreno
- Posgrado en Biomedicina Molecular, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico; Doctorado en Ciencias en Biotecnología, ENMyH, Instituto Politécnico Nacional, México City 07320, Mexico.
| |
Collapse
|
34
|
Singh M, Sharma S, Bhattacharya A, Tatu U. Heat Shock Protein 90 regulates encystation in Entamoeba. Front Microbiol 2015; 6:1125. [PMID: 26528271 PMCID: PMC4602144 DOI: 10.3389/fmicb.2015.01125] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 09/28/2015] [Indexed: 11/18/2022] Open
Abstract
Enteric protozoan Entamoeba histolytica is a major cause of debilitating diarrheal infection worldwide with high morbidity and mortality. Even though the clinical burden of this parasite is very high, this infection is categorized as a neglected disease. Parasite is transmitted through feco-oral route and exhibit two distinct stages namely – trophozoites and cysts. Mechanism and regulation of encystation is not clearly understood. Previous studies have established the role of Heat shock protein 90 (Hsp90) in regulating stage transition in various protozoan parasites like Giardia, Plasmodium, Leishmania, and Toxoplasma. Our study for the first time reports that Hsp90 plays a crucial role in life cycle of Entamoeba as well. We identify Hsp90 to be a negative regulator of encystation in Entamoeba. We also show that Hsp90 inhibition interferes with the process of phagocytosis in Entamoeba. Overall, we show that Hsp90 plays an important role in virulence and transmission of Entamoeba.
Collapse
Affiliation(s)
- Meetali Singh
- Department of Biochemistry, Indian Institute of Science Bangalore, India
| | - Shalini Sharma
- School of Life Sciences, Jawaharlal Nehru University New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University New Delhi, India
| | - Utpal Tatu
- Department of Biochemistry, Indian Institute of Science Bangalore, India
| |
Collapse
|
35
|
Avalos-Padilla Y, Betanzos A, Javier-Reyna R, García-Rivera G, Chávez-Munguía B, Lagunes-Guillén A, Ortega J, Orozco E. EhVps32 Is a Vacuole-Associated Protein Involved in Pinocytosis and Phagocytosis of Entamoeaba histolytica. PLoS Pathog 2015; 11:e1005079. [PMID: 26230715 PMCID: PMC4521941 DOI: 10.1371/journal.ppat.1005079] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 07/11/2015] [Indexed: 12/31/2022] Open
Abstract
Here, we investigated the role of EhVps32 protein (a member of the endosomal-sorting complex required for transport) in endocytosis of Entamoeba histolytica, a professional phagocyte. Confocal microscopy, TEM and cell fractionation revealed EhVps32 in cytoplasmic vesicles and also located adjacent to the plasma membrane. Between 5 to 30 min of phagocytosis, EhVps32 was detected on some erythrocytes-containing phagosomes of acidic nature, and at 60 min it returned to cytoplasmic vesicles and also appeared adjacent to the plasma membrane. TEM images revealed it in membranous structures in the vicinity of ingested erythrocytes. EhVps32, EhADH (an ALIX family member), Gal/GalNac lectin and actin co-localized in the phagocytic cup and in some erythrocytes-containing phagosomes, but EhVps32 was scarcely detected in late phagosomes. During dextran uptake, EhVps32, EhADH and Gal/GalNac lectin, but not actin, co-localized in pinosomes. EhVps32 recombinant protein formed oligomers composed by rings and filaments. Antibodies against EhVps32 monomers stained cytoplasmic vesicles but not erythrocytes-containing phagosomes, suggesting that in vivo oligomers are formed on phagosome membranes. The involvement of EhVps32 in phagocytosis was further study in pNeoEhvps32-HA-transfected trophozoites, which augmented almost twice their rate of erythrophagocytosis as well as the membranous concentric arrays built by filaments, spirals and tunnel-like structures. Some of these structures apparently connected phagosomes with the phagocytic cup. In concordance, the EhVps32-silenced G3 trophozoites ingested 80% less erythrocytes than the G3 strain. Our results suggest that EhVps32 participates in E. histolytica phagocytosis and pinocytosis. It forms oligomers on erythrocytes-containing phagosomes, probably as a part of the scission machinery involved in membrane invagination and intraluminal vesicles formation. Trophozoites of E. histolytica represent an excellent model to study endosomal-sorting complex required for transport components due to their high endocytic activity and vesicle trafficking. The key role of EhVps32 on phagocytosis is supported by: i) its presence on phagosomes, ii) its interaction with EhADH (an erythrocytes receptor), Gal/GalNac lectin and actin, iii) the higher rate of erythrophagocytosis showed by EhVps32 overexpressing trophozoites, iv) the diminish rate of phagocytosis in EhVps32-silenced G3 trophozoites, and v) its location in erythrocytes-containing acidic phagosomes. Here, we discovered the presence of membranous concentric helicoidally and tunnel-like structures constituted by EhVps32 and EhADH that may have a dynamic role in membrane remodeling and in the generation of intraluminal vesicles in the phagosomes. Elucidating molecular mechanisms of endocytosis-exocytosis pathways will help us to better understand the pathogenic process of E. histolytica and develop new drugs for diagnosis and vaccine methods.
Collapse
Affiliation(s)
- Yunuen Avalos-Padilla
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Abigail Betanzos
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Rosario Javier-Reyna
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Guillermina García-Rivera
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Anel Lagunes-Guillén
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Jaime Ortega
- Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
- * E-mail:
| |
Collapse
|
36
|
Ralston KS. Chew on this: amoebic trogocytosis and host cell killing by Entamoeba histolytica. Trends Parasitol 2015; 31:442-52. [PMID: 26070402 DOI: 10.1016/j.pt.2015.05.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 05/04/2015] [Accepted: 05/05/2015] [Indexed: 01/23/2023]
Abstract
Entamoeba histolytica was named 'histolytica' (from histo-, 'tissue'; lytic-, 'dissolving') for its ability to destroy host tissues. Direct killing of host cells by the amoebae is likely to be the driving factor that underlies tissue destruction, but the mechanism was unclear. We recently showed that, after attaching to host cells, amoebae bite off and ingest distinct host cell fragments, and that this contributes to cell killing. We review this process, termed 'amoebic trogocytosis' (trogo-, 'nibble'), and how this process interplays with phagocytosis, or whole cell ingestion, in this organism. 'Nibbling' processes have been described in other microbes and in multicellular organisms. The discovery of amoebic trogocytosis in E. histolytica may also shed light on an evolutionarily conserved process for intercellular exchange.
Collapse
Affiliation(s)
- Katherine S Ralston
- Department of Microbiology and Molecular Genetics, University of California, Davis, CA 95616, USA.
| |
Collapse
|
37
|
Picazarri K, Nakada-Tsukui K, Tsuboi K, Miyamoto E, Watanabe N, Kawakami E, Nozaki T. Atg8 is involved in endosomal and phagosomal acidification in the parasitic protist Entamoeba histolytica. Cell Microbiol 2015; 17:1510-22. [PMID: 25923949 PMCID: PMC4744732 DOI: 10.1111/cmi.12453] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 04/09/2015] [Accepted: 04/23/2015] [Indexed: 01/08/2023]
Abstract
Autophagy is one of two major bulk protein degradation systems and is conserved throughout eukaryotes. The protozoan Entamoeba histolytica, which is a human intestinal parasite, possesses a restricted set of autophagy‐related (Atg) proteins compared with other eukaryotes and thus represents a suitable model organism for studying the minimal essential components and ancestral functions of autophagy. E. histolytica possesses two conjugation systems: Atg8 and Atg5/12, although a gene encoding Atg12 is missing in the genome. Atg8 is considered to be the central and authentic marker of autophagosomes, but recent studies have demonstrated that Atg8 is not exclusively involved in autophagy per se, but other fundamental mechanisms of vesicular traffic. To investigate this question in E. histolytica, we studied on Atg8 during the proliferative stage. Atg8 was constitutively expressed in both laboratory‐maintained and recently established clinical isolates and appeared to be lipid‐modified in logarithmic growth phase, suggesting a role of Atg8 in non‐stress and proliferative conditions. These findings are in contrast to those for Entamoeba invadens, in which autophagy is markedly induced during an early phase of differentiation from the trophozoite into the cyst. The repression of Atg8 gene expression in En. histolytica by antisense small RNA‐mediated transcriptional gene silencing resulted in growth retardation, delayed endocytosis and reduced acidification of endosomes and phagosomes. Taken together, these results suggest that Atg8 and the Atg8 conjugation pathway have some roles in the biogenesis of endosomes and phagosomes in this primitive eukaryote.
Collapse
Affiliation(s)
- Karina Picazarri
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kumiko Tsuboi
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Eri Miyamoto
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan
| | - Naoko Watanabe
- Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan
| | - Eiryo Kawakami
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Laboratory for Disease Systems Modeling, RIKEN Center for integrative Medical Sciences, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, Japan
| | - Tomoyoshi Nozaki
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| |
Collapse
|
38
|
Unconventional actins and actin-binding proteins in human protozoan parasites. Int J Parasitol 2015; 45:435-47. [DOI: 10.1016/j.ijpara.2015.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 12/19/2014] [Accepted: 01/27/2015] [Indexed: 12/11/2022]
|
39
|
Binding and Endocytosis of Bovine Hololactoferrin by the Parasite Entamoeba histolytica. BIOMED RESEARCH INTERNATIONAL 2015; 2015:375836. [PMID: 26090404 PMCID: PMC4450225 DOI: 10.1155/2015/375836] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/11/2014] [Accepted: 09/16/2014] [Indexed: 11/26/2022]
Abstract
Entamoeba histolytica is a human parasite that requires iron (Fe) for its metabolic function and virulence. Bovine lactoferrin (B-Lf) and its peptides can be found in the digestive tract after dairy products are ingested. The aim of this study was to compare virulent trophozoites recently isolated from hamster liver abscesses with nonvirulent trophozoites maintained for more than 30 years in cultures in vitro regarding their interaction with iron-charged B-Lf (B-holo-Lf). We performed growth kinetics analyses of trophozoites in B-holo-Lf and throughout several consecutive transfers. The virulent parasites showed higher growth and tolerance to iron than nonvirulent parasites. Both amoeba variants specifically bound B-holo-Lf with a similar Kd. However, averages of 9.45 × 105 and 6.65 × 106 binding sites/cell were found for B-holo-Lf in nonvirulent and virulent amoebae, respectively. Virulent amoebae bound more efficiently to human and bovine holo-Lf, human holo-transferrin, and human and bovine hemoglobin than nonvirulent amoebae. Virulent amoebae showed two types of B-holo-Lf binding proteins. Although both amoebae endocytosed this glycoprotein through clathrin-coated vesicles, the virulent amoebae also endocytosed B-holo-Lf through a cholesterol-dependent mechanism. Both amoeba variants secreted cysteine proteases cleaving B-holo-Lf. These data demonstrate that the B-Lf endocytosis is more efficient in virulent amoebae.
Collapse
|
40
|
Mansuri MS, Bhattacharya S, Bhattacharya A. A novel alpha kinase EhAK1 phosphorylates actin and regulates phagocytosis in Entamoeba histolytica. PLoS Pathog 2014; 10:e1004411. [PMID: 25299184 PMCID: PMC4192601 DOI: 10.1371/journal.ppat.1004411] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 08/19/2014] [Indexed: 01/09/2023] Open
Abstract
Phagocytosis plays a key role in nutrient uptake and virulence of the protist parasite Entamoeba histolytica. Phagosomes have been characterized by proteomics, and their maturation in the cells has been studied. However, there is so far not much understanding about initiation of phagocytosis and formation of phagosomes at the molecular level. Our group has been studying initiation of phagocytosis and formation of phagosomes in E. histolytica, and have described some of the molecules that play key roles in the process. Here we show the involvement of EhAK1, an alpha kinase and a SH3 domain containing protein in the pathway that leads to formation of phagosomes using red blood cell as ligand particle. A number of approaches, such as proteomics, biochemical, confocal imaging using specific antibodies or GFP tagged molecules, expression down regulation by antisense RNA, over expression of wild type and mutant proteins, were used to understand the role of EhAK1 in phagocytosis. EhAK1 was found in the phagocytic cups during the progression of cups, until closure of phagosomes, but not in the phagosomes themselves. It is recruited to the phagosomes through interaction with the calcium binding protein EhCaBP1. A reduction in phagocytosis was observed when EhAK1 was down regulated by antisense RNA, or by over expression of the kinase dead mutant. G-actin was identified as one of the major substrates of EhAK1. Phosphorylated actin preferentially accumulated at the phagocytic cups and over expression of a phosphorylation defective actin led to defects in phagocytosis. In conclusion, we describe an important component of the pathway that is initiated on attachment of red blood cells to E. histolytica cells. The main function of EhAK1 is to couple signalling events initiated after accumulation of EhC2PK to actin dynamics.
Collapse
Affiliation(s)
- M. Shahid Mansuri
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
- * E-mail:
| |
Collapse
|
41
|
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.
Collapse
|
42
|
Koushik AB, Welter BH, Rock ML, Temesvari LA. A genomewide overexpression screen identifies genes involved in the phosphatidylinositol 3-kinase pathway in the human protozoan parasite Entamoeba histolytica. EUKARYOTIC CELL 2014; 13:401-11. [PMID: 24442890 PMCID: PMC3957588 DOI: 10.1128/ec.00329-13] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 01/12/2014] [Indexed: 11/20/2022]
Abstract
Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. E. histolytica relies on motility, phagocytosis, host cell adhesion, and proteolysis of extracellular matrix for virulence. In eukaryotic cells, these processes are mediated in part by phosphatidylinositol 3-kinase (PI3K) signaling. Thus, PI3K may be critical for virulence. We utilized a functional genomics approach to identify genes whose products may operate in the PI3K pathway in E. histolytica. We treated a population of trophozoites that were overexpressing genes from a cDNA library with a near-lethal dose of the PI3K inhibitor wortmannin. This screen was based on the rationale that survivors would be overexpressing gene products that directly or indirectly function in the PI3K pathway. We sequenced the overexpressed genes in survivors and identified a cDNA encoding a Rap GTPase, a protein previously shown to participate in the PI3K pathway. This supports the validity of our approach. Genes encoding a coactosin-like protein, EhCoactosin, and a serine-rich E. histolytica protein (SREHP) were also identified. Cells overexpressing EhCoactosin or SREHP were also less sensitive to a second PI3K inhibitor, LY294002. This corroborates the link between these proteins and PI3K. Finally, a mutant cell line with an increased level of phosphatidylinositol (3,4,5)-triphosphate, the product of PI3K activity, exhibited increased expression of SREHP and EhCoactosin. This further supports the functional connection between these proteins and PI3K in E. histolytica. To our knowledge, this is the first forward-genetics screen adapted to reveal genes participating in a signal transduction pathway in this pathogen.
Collapse
Affiliation(s)
- Amrita B. Koushik
- Department of Genetics and Biochemistry, Clemson University, Clemson, South Carolina, USA
- Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, South Carolina, USA
| | - Brenda H. Welter
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
- Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, South Carolina, USA
| | - Michelle L. Rock
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
- Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, South Carolina, USA
| | - Lesly A. Temesvari
- Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA
- Eukaryotic Pathogens Innovation Center (EPIC), Clemson University, Clemson, South Carolina, USA
| |
Collapse
|
43
|
Maravillas-Montero JL, López-Ortega O, Patiño-López G, Santos-Argumedo L. Myosin 1g regulates cytoskeleton plasticity, cell migration, exocytosis, and endocytosis in B lymphocytes. Eur J Immunol 2014; 44:877-86. [PMID: 24310084 DOI: 10.1002/eji.201343873] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 10/22/2013] [Accepted: 11/27/2013] [Indexed: 11/07/2022]
Abstract
Myosin 1g (Myo1g) is a hematopoietic-specific myosin expressed mainly by lymphocytes. Here, we report the localization of Myo1g in B-cell membrane compartments such as lipid rafts, microvilli, and membrane extensions formed during spreading. By using Myo1g-deficient mouse B cells, we detected abnormalities in the adhesion ability and chemokine-induced directed migration of these lymphocytes. We also assessed a role for Myo1g in phagocytosis and exocytosis processes, as these were also irregular in Myo1g-deficient B cells. Taken together, our results show that Myo1g acts as a main regulator of different membrane/cytoskeleton-dependent processes in B lymphocytes.
Collapse
Affiliation(s)
- José L Maravillas-Montero
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, México
| | | | | | | |
Collapse
|
44
|
López-Camarillo C, López-Rosas I, Ospina-Villa JD, Marchat LA. Deciphering molecular mechanisms of mRNA metabolism in the deep-branching eukaryoteEntamoeba histolytica. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 5:247-62. [DOI: 10.1002/wrna.1205] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 10/04/2013] [Accepted: 10/09/2013] [Indexed: 11/05/2022]
Affiliation(s)
| | - Itzel López-Rosas
- Genomics Sciences Program; Autonomous University of Mexico City; Mexico City Mexico
| | - Juan David Ospina-Villa
- Institutional Program of Molecular Biomedicine; National School of Medicine and Homeopathy of the National Polytechnic Institute; Mexico City Mexico
| | - Laurence A. Marchat
- Institutional Program of Molecular Biomedicine; National School of Medicine and Homeopathy of the National Polytechnic Institute; Mexico City Mexico
- Biotechnology Program; National School of Medicine and Homeopathy of the National Polytechnic Institute; Mexico City Mexico
| |
Collapse
|
45
|
Abstract
The parasite Entamoeba histolytica causes amebic colitis and systemic amebiasis. Among the known amebic factors contributing to pathogenesis are signaling pathways involving heterotrimeric and Ras superfamily G proteins. Here, we review the current knowledge of the roles of heterotrimeric G protein subunits, Ras, Rho and Rab GTPase families in E. histolytica pathogenesis, as well as of their downstream signaling effectors and nucleotide cycle regulators. Heterotrimeric G protein signaling likely modulates amebic motility and attachment to and killing of host cells, in part through activation of an RGS-RhoGEF (regulator of G protein signaling-Rho guanine nucleotide exchange factor) effector. Rho family GTPases, as well as RhoGEFs and Rho effectors (formins and p21-activated kinases) regulate the dynamic actin cytoskeleton of E. histolytica and associated pathogenesis-related cellular processes, such as migration, invasion, phagocytosis and evasion of the host immune response by surface receptor capping. A remarkably large family of 91 Rab GTPases has multiple roles in a complex amebic vesicular trafficking system required for phagocytosis and pinocytosis and secretion of known virulence factors, such as amebapores and cysteine proteases. Although much remains to be discovered, recent studies of G protein signaling in E. histolytica have enhanced our understanding of parasitic pathogenesis and have also highlighted possible targets for pharmacological manipulation.
Collapse
|
46
|
Juárez-Hernández LJ, García-Pérez RM, Salas-Casas A, García-Rivera G, Orozco E, Rodríguez MA. Entamoeba histolytica: the over expression of a mutated EhRabB protein produces a decrease of in vitro and in vivo virulence. Exp Parasitol 2012; 133:339-45. [PMID: 23268174 DOI: 10.1016/j.exppara.2012.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Revised: 12/11/2012] [Accepted: 12/13/2012] [Indexed: 12/25/2022]
Abstract
Vesicular trafficking, which is implicated in secretion of cytolytic molecules as well as in phagocytosis, plays an important role in the pathogenic mechanism of Entamoeba histolytica, the protozoan parasite causative of human amoebiasis. Thus, Rab GTPases, that are key regulators of vesicle trafficking, should be considered as molecules involved in the parasite virulence. EhRabB is a Rab protein located in cytoplasmic vesicles that are translocated to phagocytic mouths during ingestion of target cells, suggesting that this Rab protein is involved in phagocytosis. To prove this hypothesis, we over expressed the wild type EhrabB gene and a mutant gene encoding for a protein (RabBN118I) unable to bind guanine nucleotides and therefore constitutively inactive. The over expression of the mutated protein in E. histolytica trophozoites provoked a dominant negative effect, reflected in a significant decrease of both phagocytosis and cytopathic effect as well as in a failure to produce hepatic abscesses in hamsters. These results confirm that EhRabB is involved in phagocytosis and virulence of E. histolytica.
Collapse
Affiliation(s)
- L J Juárez-Hernández
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del IPN, A.P. 14-740, México D.F. 07000, Mexico
| | | | | | | | | | | |
Collapse
|
47
|
Vaithilingam A, Teixeira JE, Huston CD. Endoplasmic reticulum continuity in the protozoan parasite Entamoeba histolytica: Evolutionary implications and a cautionary note. Commun Integr Biol 2012; 1:172-4. [PMID: 19704884 DOI: 10.4161/cib.1.2.7143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Accepted: 10/03/2008] [Indexed: 11/19/2022] Open
Abstract
Entamoeba histolytica has been described as an early branching eukaryotic parasite based on the lack of organelles such as mitochondria and peroxisomes, and on morphologic studies that concluded it possesses a vesicular endoplasmic reticulum (ER) and Golgi complex. However, a recent study from our laboratory showed that the E. histolytica ER is continuous by using an ER-targeted green fluorescent protein fusion protein and photobleaching experiments. We proposed that the vesicular ER seen earlier was likely an artifact of fixation. We now report data using an alternative fixation protocol that preserves the continuous ER morphology. These data confirm that the vesicular ER reported earlier was indeed a fixation artifact; furthermore, since we observed the same ER structure when staining for the native antigen HSP-70 in wild-type amebae, the data provide direct evidence that the continuous ER morphology we reported is correct. This work has important implications for cell biologists studying E. histolytica virulence, emphasizes the frequent need to reassess assumptions based on published data, and provides additional evidence that E. histolytica actually diverged relatively late in evolution and that many of its unusual features are likely due to loss of features during adaptation to its ecological niche.
Collapse
|
48
|
A functional study of nucleocytoplasmic transport signals of the EhNCABP166 protein from Entamoeba histolytica. Parasitology 2012; 139:1697-710. [PMID: 22906852 DOI: 10.1017/s0031182012001199] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
EhNCABP166 is an Entamoeba histolytica actin-binding protein that localizes to the nucleus and cytoplasm. Bioinformatic analysis of the EhNCABP166 amino acid sequence shows the presence of 3 bipartite nuclear localization signals (NLS) and a nuclear export signal (NES). The present study aimed to investigate the functionality of these signals in 3 ways. First, we fused each potential NLS to a cytoplasmic domain of ehFLN to determine whether the localization of this domain could be altered by the presence of the NLSs. Furthermore, the localization of each domain of EhNCABP166 was determined. Similarly, we generated mutations in the first block of bipartite signals from the domains that contained these signals. Additionally, we added an NES to 2 constructs that were then evaluated. We confirmed the intranuclear localization of EhNCABP166 using transmission electron microscopy. Fusion of each NLS resulted in shuttling of the cytoplasmic domain to the nucleus. With the exception of 2 domains, all of the evaluated domains localized within the nucleus. A mutation in the first block of bipartite signals affected the localization of the domains containing an NLS. The addition of an NES shifted the localization of these domains to the cytoplasm. The results presented here establish EhNCABP166 as a protein containing functional nuclear localization signals and a nuclear export signal.
Collapse
|
49
|
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.
Collapse
|
50
|
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.
Collapse
Affiliation(s)
- I W Wilson
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | | |
Collapse
|