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Gómez-Conde E, Vargas-Mejía MÁ, Díaz-Orea MA, Hernández-Rivas R, Cárdenas-Perea ME, Guerrero-González T, González-Barrios JA, Montiel-Jarquín ÁJ. Detection of beta-tubulin in the cytoplasm of the interphasic Entamoeba histolytica trophozoites. Exp Parasitol 2016; 167:38-42. [PMID: 27156446 DOI: 10.1016/j.exppara.2016.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 03/17/2016] [Accepted: 05/05/2016] [Indexed: 10/21/2022]
Abstract
It is known that the microtubules (MT) of Entamoeba histolytica trophozoites form an intranuclear mitotic spindle. However, electron microscopy studies and the employment of anti-beta-tubulin (β-tubulin) antibodies have not exhibited these cytoskeletal structures in the cytoplasm of these parasites. The purpose of this work was to detect β-tubulin in the cytoplasm of interphasic E. histolytica trophozoites. Activated or non-activated HMI-IMSS-strain E. histolytica trophozoites were used and cultured for 72 h at 37 °C in TYI-S-33 medium, and then these were incubated with the anti-β-tubulin antibody of E. histolytica. The anti-β-tubulin antibody reacted with the intranuclear mitotic spindle of E. histolytica-activated trophozoites as control. In contrast, in non-activated interphasic parasites, anti-β-tubulin antibody reacted with diverse puntiform structures in the cytoplasm and with ring-shaped structures localized in the cytoplasm, cellular membrane and endocytic stomas. In this work, for the first time, the presence of β-tubulin is shown in the cytoplasm of E. histolytica trophozoites.
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Affiliation(s)
- Eduardo Gómez-Conde
- División de Investigación en Salud, Unidad Médica de Alta Especialidad (UMAE), Hospital de Especialidades, Centro Médico Nacional General de División "Manuel Ávila Camacho", Instituto Mexicano del Seguro Social (IMSS), Calle 2 Norte 2004, Col. Centro, 72000 Puebla, Mexico; Laboratorio de Investigación en Inmunobiología, Facultad de Medicina, Benemérita Universidad Autónoma de Puebla (BUAP), Calle 13 Sur 2706, Col. Volcanes, 72410 Puebla, Mexico.
| | - Miguel Ángel Vargas-Mejía
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Av. Instituto Politécnico Nacional 2508, Delegación Gustavo A. Madero, Col.San Pedro Zacatenco, 07360 México, D.F., Mexico.
| | - María Alicia Díaz-Orea
- Laboratorio de Investigación en Inmunobiología, Facultad de Medicina, Benemérita Universidad Autónoma de Puebla (BUAP), Calle 13 Sur 2706, Col. Volcanes, 72410 Puebla, Mexico.
| | - Rosaura Hernández-Rivas
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Av. Instituto Politécnico Nacional 2508, Delegación Gustavo A. Madero, Col.San Pedro Zacatenco, 07360 México, D.F., Mexico.
| | - María Elena Cárdenas-Perea
- Laboratorio de Investigación en Inmunobiología, Facultad de Medicina, Benemérita Universidad Autónoma de Puebla (BUAP), Calle 13 Sur 2706, Col. Volcanes, 72410 Puebla, Mexico.
| | - Tayde Guerrero-González
- Servicio de Traumatología y Ortopedia, Hospital Regional 1(o) de Octubre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Av. Instituto Politécnico Nacional 1669, Gustavo A. Madero, Col. Magdalena de las Salinas, Del. Gustavo A. Madero, 07760 México D.F., Mexico.
| | - Juan Antonio González-Barrios
- Laboratorio de Medicina Genómica, Hospital Regional 1 de Octubre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Avenida Instituto Politécnico Nacional N° 1669, Gustavo A. Madero, Col. Magdalena de las Salinas, Del. Gustavo A. Madero, 07760 México, D.F., Mexico.
| | - Álvaro José Montiel-Jarquín
- Jefatura de División de Investigación en Salud, UMAE, Hospital de Traumatología, Instituto Mexicano del Seguro Social, Diagonal Defensores de la República y 6 Poniente, Col. Amor, 72140 Puebla, Mexico.
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Lohia A, Mukherjee C, Majumder S, Dastidar PG. Genome re-duplication and irregular segregation occur during the cell cycle of Entamoeba histolytica. Biosci Rep 2008; 27:373-84. [PMID: 17592766 DOI: 10.1007/s10540-007-9058-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Heterogeneity of genome content is commonly observed in axenic cultures of Entamoeba histolytica. Cells with multiple nuclei and nuclei with heterogenous genome contents suggest that regulatory mechanisms that ensure alternation of DNA synthesis and mitosis are absent in this organism. Therefore, several endo-reduplicative cycles may occur without mitosis. The data also shows that unlike other endo-reduplicating organisms, E.histolytica does not undergo a precise number of endo-reduplicative cycles. We propose that irregular endo-reduplication and genome partitioning lead to heterogeneity in the genome content of E.histolytica trophozoites in their proliferative phase. The goal of future studies should be aimed at understanding the mechanisms that are involved in (a) accumulation of multiple genome contents in a single nucleus; (b) genome segregation in nuclei that contain multiple genome contents and (c) maintenance of genome fidelity in E. histolytica.
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Affiliation(s)
- Anuradha Lohia
- Department of Biochemistry, Bose Institute, Kolkata, 700054, India.
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Abstract
The eukaryotic cytoskeleton appears to have evolved from ancestral precursors related to prokaryotic FtsZ and MreB. FtsZ and MreB show 40-50% sequence identity across different bacterial and archaeal species. Here I suggest that this represents the limit of divergence that is consistent with maintaining their functions for cytokinesis and cell shape. Previous analyses have noted that tubulin and actin are highly conserved across eukaryotic species, but so divergent from their prokaryotic relatives as to be hardly recognizable from sequence comparisons. One suggestion for this extreme divergence of tubulin and actin is that it occurred as they evolved very different functions from FtsZ and MreB. I will present new arguments favoring this suggestion, and speculate on pathways. Moreover, the extreme conservation of tubulin and actin across eukaryotic species is not due to an intrinsic lack of variability, but is attributed to their acquisition of elaborate mechanisms for assembly dynamics and their interactions with multiple motor and binding proteins. A new structure-based sequence alignment identifies amino acids that are conserved from FtsZ to tubulins. The highly conserved amino acids are not those forming the subunit core or protofilament interface, but those involved in binding and hydrolysis of GTP.
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Affiliation(s)
- Harold P Erickson
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710-3709, USA.
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Dastidar PG, Majumder S, Lohia A. Eh Klp5 is a divergent member of the kinesin 5 family that regulates genome content and microtubular assembly in Entamoeba histolytica. Cell Microbiol 2007; 9:316-28. [PMID: 16925786 DOI: 10.1111/j.1462-5822.2006.00788.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Earlier studies have established two unusual features in the cell division cycle of Entamoeba histolytica. First, microtubules form a radial assembly instead of a bipolar mitotic spindle, and second, the genome content of E. histolytica cells varied from 1x to 6x or more. In this study, Eh Klp5 was identified as a divergent member of the BimC kinesin family that is known to regulate formation and stabilization of the mitotic spindle in other eukaryotes. In contrast to earlier studies, we show here that bipolar microtubular spindles were formed in E. histolytica but were visible only in 8-12% of the cells after treatment with taxol. The number of bipolar spindles was significantly increased in Eh Klp5 stable transformants (20-25%) whereas Eh Klp5 double-stranded RNA (dsRNA) transformants did not show any spindles (< 1%). The genome content of Eh Klp5 stable transformants was regulated between 1x and 2x unlike control cells. Binucleated cells accumulated in Eh Klp5 dsRNA transformants and after inhibition of Eh Klp5 with small molecule inhibitors in control cells, suggesting that cytokinesis was delayed in the absence of Eh Klp5. Taken together, our results indicate that Eh Klp5 regulates microtubular assembly, genome content and cell division in E. histolytica. Additionally, Eh Klp5 showed alterations in its drug-binding site compared with its human homologue, Hs Eg5 and this was reflected in its reduced sensitivity to Eg5 inhibitors - monastrol and HR22C16 analogues.
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Meza I, Talamás-Rohana P, Vargas MA. The Cytoskeleton of Entamoeba histolytica: Structure, Function, and Regulation by Signaling Pathways. Arch Med Res 2006; 37:234-43. [PMID: 16380324 DOI: 10.1016/j.arcmed.2005.09.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2005] [Accepted: 09/26/2005] [Indexed: 01/16/2023]
Abstract
Pathogenesis in the parasite Entamoeba histolytica has been related to motility of the trophozoites. Motility is an important feature in amebas as they perform multiple motile functions during invasion of host tissues. As motility depends on the organization and regulation of the cytoskeleton elements, in particular of the actin cytoskeleton, the study of the molecular components of the machinery responsible for movement has been a key aspect to study in this parasite. Although many of the components have high homology in amino acid sequence and function to those characterized in higher eukaryotic cells, there are important differences to suggest that parasitic organisms may have developed adaptative differences that could be useful as targets to stop invasion. The purpose of this review is to evaluate current knowledge about the cytoskeleton of E. histolytica and the ways in which the parasite controls motility.
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Affiliation(s)
- Isaura Meza
- Departamentos de Biomedicina Molecular, Centro de Investigación y de Estudios, Avanzados del IPN, México D.F., México.
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Vega-Robledo GB, Leandro E, Silva R, Olivos A, Rico G. Effect of Zinc-Treated Entamoeba histolytica on the Human Polymorphonuclear Respiratory Burst. Arch Med Res 2005; 36:75-9. [PMID: 15778000 DOI: 10.1016/j.arcmed.2004.10.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2004] [Accepted: 10/01/2004] [Indexed: 11/20/2022]
Abstract
One of the mechanisms that Entamoeba histolytica uses to evade host immune response is inhibition of the polymorphonuclear (PMN) leukocyte respiratory burst. In studies previously conducted in a model used in our laboratory, we observed that when treating trophozoites with different zinc concentrations certain amebic functions are inhibited while significantly limiting development of hepatic abscess in golden hamsters (Mesocricetus aureatus). We carried out an in vitro study using a chemoluminescent method to assess the effect zinc-treated amebic trophozoites exercise on respiratory burst in human PMNs. We measured response of PMNs incubated with E. histolytica trophozoites from cultures with TYI-S33 medium alone and with zinc. Zinc concentrations between 0.1 and 1.0 mM did not affect amebic trophozoite viability, and PMNs in contact with these in a zinc-free medium had an oxidative response similar to that obtained with zymosan and significantly greater (p <0.05) than that generated by cells co-incubated with amebas cultured in TYI-S33 medium alone. These results suggest that zinc alters the amebic mechanism that inhibits the oxidative function of human polymorphonuclear leukocyte.
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Affiliation(s)
- Gloria B Vega-Robledo
- Departamento de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), México D.F., México.
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Abstract
Entamoeba histolytica, is a microaerophilic protist, which causes amoebic dysentery in humans. This unicellular organism proliferates in the human intestine as the motile trophozoite and survives the hostile environment outside the human host as the dormant quadri-nucleate cyst. Lack of organelles--such as mitochondria and Golgi bodies--and an unequal mode of cell division, led to the popular belief, that this organism preceded other eukaryotes during evolution. However, data from several laboratories have shown that, contrary to this belief, E. histolytica is remarkable in its divergence from other eukaryotes. This uniqueness is witnessed in many aspects of its biochemical pathways, cellular biology and genetic diversity. In this context, I have analysed the cell division cycle of this organism and compared it to that of other eukaryotes. Studies on E. histolytica, suggest that in its proliferative phase, this organism may accumulate polyploid cells. Thus 'checkpoints' regulating alternation of genome duplication and cell division appear to be absent in this unicellular protist. Sequence homologs of several cell cycle regulating proteins have been identified in amoeba, but their structural divergence suggests that they may not have equivalent function in this organism. The regulation of cell proliferation in E. histolytica, may be ideally suited to survival of a parasite in a complex host. Analysis of these molecular details may offer solutions for eradicating the pathogen by hitherto unknown methods.
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Affiliation(s)
- Anuradha Lohia
- Department of Biochemistry, Bose Institute, Kolkata, India.
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Roy D, Lohia A. Sequence divergence of Entamoeba histolytica tubulin is responsible for its altered tertiary structure. Biochem Biophys Res Commun 2004; 319:1010-6. [PMID: 15184082 DOI: 10.1016/j.bbrc.2004.05.079] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Indexed: 11/29/2022]
Abstract
Atypical microtubular structures of the protozoan parasite Entamoeba histolytica (Eh) have been attributed to amino acid sequence divergence of Eh tubulin. To investigate if this sequence divergence leads to significant differences in the tertiary structure of the Eh alphabeta-tubulin heterodimer, we have modeled alphabeta-tubulin heterodimer of Eh based on the crystal structure of mammalian tubulin. The predicted 3D homology model exhibits an overall resemblance with the known crystal structure of mammalian tubulin except for the 16 residue long carboxy terminal region of Eh beta-tubulin. We propose that this C-terminal region may provide steric hindrance in the polymerization of Eh alphabeta-tubulin for microtubule formation. Using docking studies, we have identified the binding sites for different microtubule specific drugs on Eh beta-tubulin. Our model provides a rational framework, both for understanding the contribution of Eh beta-tubulin C-terminal region to alphabeta-tubulin polymerization and design of new anti-protozoan drugs in order to control amoebiasis.
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Affiliation(s)
- Debjani Roy
- Bioinformatics Centre, Bose Institute, Kolkata, India
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de Lourdes Muñoz M, Das P, Tovar R. Entamoeba histolytica trophozoites activated by collagen type I and Ca(2+) have a structured cytoskeleton during collagenase secretion. CELL MOTILITY AND THE CYTOSKELETON 2001; 50:45-54. [PMID: 11746671 DOI: 10.1002/cm.1040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A peculiar characteristic of Entamoeba histolytica trophozoites is their capacity to invade human tissues. One of the cellular determinants of invasion may include adhesion to extracellular matrix components such as collagen, induction, and secretion of electron-dense granules (EDG) and tissue digestion. The mechanism and receptors involved in this process are not well understood. Previous results suggested that cytoskeleton plays a very important role during EDG secretion. We present evidence suggesting that adhesion to collagen and activation of EDG secretion are integrin-dependent events, since beta1 subunits detected by antibodies are concentrated at membrane sites where collagen and actin were colocalized. Furthermore, the involvement of actin, vimentin, and tubulin in restructuring cytoskeleton during EDG secretion was evident, since cytoskeleton isolation was possible exclusively in activated cells. Studies of immunolocalization of tubulin, actin, and vimentin by immunofluorescence and transmission electron microscopy suggest a role for cytoskeleton in EDG secretion.
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Affiliation(s)
- M de Lourdes Muñoz
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Zacatenco, México.
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Edgcomb VP, Roger AJ, Simpson AG, Kysela DT, Sogin ML. Evolutionary relationships among "jakobid" flagellates as indicated by alpha- and beta-tubulin phylogenies. Mol Biol Evol 2001; 18:514-22. [PMID: 11264402 DOI: 10.1093/oxfordjournals.molbev.a003830] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Jakobids are free-living, heterotrophic flagellates that might represent early-diverging mitochondrial protists. They share ultrastructural similarities with eukaryotes that occupy basal positions in molecular phylogenies, and their mitochondrial genome architecture is eubacterial-like, suggesting a close affinity with the ancestral alpha-proteobacterial symbiont that gave rise to mitochondria and hydrogenosomes. To elucidate relationships among jakobids and other early-diverging eukaryotic lineages, we characterized alpha- and beta-tubulin genes from four jakobids: Jakoba libera, Jakoba incarcerata, Reclinomonas americana (the "core jakobids"), and Malawimonas jakobiformis. These are the first reports of nuclear genes from these organisms. Phylogenies based on alpha-, beta-, and combined alpha- plus beta-tubulin protein data sets do not support the monophyly of the jakobids. While beta-tubulin and combined alpha- plus beta-tubulin phylogenies showed a sister group relationship between J. libera and R. americana, the two other jakobids, M. jakobiformis and J. incarcerata, had unclear affinities. In all three analyses, J. libera, R. americana, and M. jakobiformis emerged from within a well-supported large "plant-protist" clade that included plants, green algae, cryptophytes, stramenopiles, alveolates, Euglenozoa, Heterolobosea, and several other protist groups, but not animals, fungi, microsporidia, parabasalids, or diplomonads. A preferred branching order within the plant-protist clade was not identified, but there was a tendency for the J. libera-R. americana lineage to group with a clade made up of the heteroloboseid amoeboflagellates and euglenozoan protists. Jakoba incarcerata branched within the plant-protist clade in the beta- and the combined alpha- plus beta-tubulin phylogenies. In alpha- tubulin trees, J. incarcerata occupied an unresolved position, weakly grouping with the animal/fungal/microsporidian group or with amitochondriate parabasalid and diplomonad lineages, depending on the phylogenetic method employed. Tubulin gene phylogenies were in general agreement with mitochondrial gene phylogenies and ultrastructural data in indicating that the "jakobids" may be polyphyletic. Relationships with the putatively deep-branching amitochondriate diplomonads remain uncertain.
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Affiliation(s)
- V P Edgcomb
- Josephine Bay-Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA
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Linder S, Schliwa M, Kube-Granderath E. Sequence analysis and immunofluorescence study of alpha- and beta-tubulins in Reticulomyxa filosa: implications of the high degree of beta2-tubulin divergence. CELL MOTILITY AND THE CYTOSKELETON 2000; 36:164-78. [PMID: 9015204 DOI: 10.1002/(sici)1097-0169(1997)36:2<164::aid-cm6>3.0.co;2-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have cloned and sequenced 2 alpha- and 2 beta-tubulin isoforms from the giant freshwater amoeba Reticulomyxa filosa. The microtubules of this organism exhibit some unusual properties, including the highest rates of assembly and disassembly known and the inability to be stabilized by taxol. The cloned alpha-tubulins show a high degree of identity when compared to an alpha-tubulin consensus sequence. The beta-tubulins, however, are more divergent, the beta2-tubulin being the most unusual beta-tubulin found so far. The deduced amino acid sequence of beta2 shows 55% identity to a beta-tubulin consensus sequence. It also features 51 unique exchanges which cluster in the C-terminal half of the molecule. Several unique exchanges and two insertions occur in regions adjacent to, or directly implicated in, conserved beta-tubulin functions. A phylogenetic analysis places the beta-tubulins of R. filosa in the vicinity of beta-tubulins from fungi and slime molds. Monoclonal and polyclonal antibodies raised against R. filosa tubulins show that the electrophoretic mobility of alpha- and beta-tubulins is reversed with respect to tubulins from most other sources. Immunofluorescence experiments reveal a ubiquitous distribution of both beta-tubulins in the amoebal network. Our observations suggest possible links between the aberrant primary structure of the beta2-tubulin and the unusual properties of R. filosa microtubules.
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Affiliation(s)
- S Linder
- Adolf Butenandt Institute for Cell Biology, Munich, Federal Republic of Germany
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Makioka A, Kumagai M, Ohtomo H, Kobayashi S, Takeuchi T. Effect of dinitroaniline herbicides on the growth of Entamoeba histolytica. J Parasitol 2000; 86:607-10. [PMID: 10864261 DOI: 10.1645/0022-3395(2000)086[0607:eodhot]2.0.co;2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The effect of the dinitroaniline herbicides oryzalin and trifluralin on the growth of Entamoeba histolytica was examined. Oryzalin inhibited the growth of E. histolytica strain HM-1:IMSS. Trifluralin was less effective than oryzalin for this parasite. Entamoeba histolytica was more resistant to these dinitroanilines than other parasitic protozoa examined so far, including Leishmania spp., Trypanosoma brucei, Plasmodium falciparum, Toxoplasma gondii, and Cryptosporidium parvum. Colchicine, a potent microtubule inhibitor of animal cells, was much less effective for E. histolytica, even at very high concentrations. A reptilian parasite, Entamoeba invadens strain IP-1, examined for comparison, was more resistant to these dinitroanilines than E. histolytica. Accumulation of E. histolytica trophozoites in mitosis was observed after culture in 100 microM oryzalin. The inhibitory effect of oryzalin on the growth of E. histolytica trophozoites was abrogated by removal of the drug after exposure to 100 microM for 2 days. In parallel to the recovery of growth after removal of the drug, the percentage of trophozoites in mitosis was reduced to a normal level. The results indicate that treatment of trophozoites with oryzalin arrests mitosis and that its effect is reversible. Therefore, oryzalin is a useful tool for studies relating to the cell cycle of this parasite.
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Affiliation(s)
- A Makioka
- Department of Tropical Medicine, Jikei University School of Medicine, Tokyo, Japan
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Ray SS, Gangopadhyay SS, Pande G, Samuelson J, Lohia A. Primary structure of Entamoeba histolytica gamma-tubulin and localisation of amoebic microtubule organising centres. Mol Biochem Parasitol 1997; 90:331-6. [PMID: 9497056 DOI: 10.1016/s0166-6851(97)00157-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- S S Ray
- Department of Biochemistry, Bose Institute, Calcutta, India
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Guillén N. Role of signalling and cytoskeletal rearrangements in the pathogenesis of Entamoeba histolytica. Trends Microbiol 1996; 4:191-7. [PMID: 8727599 DOI: 10.1016/0966-842x(96)10033-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Virulence of Entamoeba histolytica is characterized by intestinal tissue invasion, engulfment of host cells and the formation of liver abscesses. The actin-rich cytoskeleton of the amoeba allows rapid changes in morphology in response to signals from external stimuli. Cellular and molecular studies have described some of the proteins that participate in signalling and in cytoskeletal changes.
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Affiliation(s)
- N Guillén
- Unité de Pathogénie Microbienne Moléculaire, INSERM U389, Institut Pasteur, Paris, France.
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