Structural Determinants of Ubiquitin Conjugation in Entamoeba histolytica

Bosch, Dustin E.; Siderovski, David P.

doi:10.1074/jbc.m112.417337

Cited by 16 publications

(10 citation statements)

References 44 publications

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“…The BP found as the most significant were the cellular protein catabolic process (GO:0044257), proteolysis involved in cellular protein catabolic process (GO:0051603) and protein catabolic process (GO:0030163) all with 4 fold enrichment. SUMO is the Small Ubiquitin-related Modifier protein that is important for gene transcription regulation 35 . SUMO modifies many proteins including promoter-specific transcription factors, cofactors and chromatin-modifying enzymes.…”

Section: Resultsmentioning

confidence: 99%

Extensive transcriptome analysis correlates the plasticity of Entamoeba histolytica pathogenesis to rapid phenotype changes depending on the environment

Weber

Koutero

Dillies

et al. 2016

Sci Rep

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Amoebiasis is a human infectious disease due to the amoeba parasite Entamoeba histolytica. The disease appears in only 20% of the infections. Diversity in phenotypes may occur within the same infectious strain in the gut; for instance, parasites can be commensal (in the intestinal lumen) or pathogenic (inside the tissue). The degree of pathogenesis of clinical isolates varies greatly. These findings raise the hypothesis that genetic derivation may account for amoebic diverse phenotypes. The main goal of this study was to analyse gene expression changes of a single virulent amoebic strain in different environmental contexts where it exhibit different degrees of virulence, namely isolated from humans and maintained through animal liver passages, in contact with the human colon and short or prolonged in vitro culture. The study reveals major transcriptome changes in virulent parasites upon contact with human colon explants, including genes related to sugar metabolism, cytoskeleton rearrangement, stress responses and DNA repair. Furthermore, in long-term cultured parasites, drastic changes in gene expression for proteins with functions for proteasome and tRNA activities were found. Globally we conclude that rapid changes in gene expression rather than genetic derivation can sustain the invasive phenotype of a single virulent isolate of E. histolytica.

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Section: Resultsmentioning

confidence: 99%

Extensive transcriptome analysis correlates the plasticity of Entamoeba histolytica pathogenesis to rapid phenotype changes depending on the environment

Weber

Koutero

Dillies

et al. 2016

Sci Rep

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“…We recently reported that EhMLBP is a bi-functional protein that has a protective role in the parasite's response to heat shock by reducing the accumulation of aggregated proteins (Katz et al, 2012). Wostmann and colleagues (Wostmann et al, 1996) were the first to describe the existence a functional ubiquitin activation and conjugation pathway in E. histolytica, and its existence was later confirmed by Bosch and Siderovski (2013). In this report, we describe an interaction between EhMLBP and polyubiquitinated proteins in cytoplasmic granules that are formed in heat-shocked E. histolytica trophozoites.…”

Section: Introductionmentioning

confidence: 99%

Stress granule formation inEntamoeba histolytica: cross-talk between EhMLBP, EhRLE3 reverse transcriptase and polyubiquitinated proteins

2014

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SummaryThe Entamoeba histolytica-methylated LINEbinding protein (EhMLBP) binds to methylated repetitive DNA and is a positive regulator of a reverse transcriptase of a long interspersed nucleotide element (LINE). This protein protects trophozoites against heat shock by reducing protein aggregation. The presence of EhMLBP and polyubiquitinated proteins in heat shockinduced protein aggregates raised the question whether these proteins interact. This assumption was confirmed by co-immunoprecipitation experiments: ubiquitinated proteins were detected in the perinuclear region of non-stressed E. histolytica trophozoites, whereas ubiquitinated proteins were detected in the perinuclear region and colocalized with EhMLBP in cytoplasmic granules in heat-shocked trophozoites. We also observed that overexpression of the reverse transcriptase of EhRLE3 induced the upregulation of EhMLBP expression and the formation of these EhMLBP-containing granules. Since (i) these EhMLBP-containing granules in the cytoplasm of heat-shocked E. histolytica trophozoites also contain polyubiquitinated proteins and poly(A) + mRNA and (ii) their formation is promoted by sodium arsenate, puromycin, and pateamine A and is inhibited by cycloheximide, we propose that these cytoplasmic EhMLBP-containing granules are stress granules. Our data also suggest that the formation of these granules is dependent upon EhMLBP and LINE.

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“…Therefore, the increase in the MW of the EhTRF-like I and III proteins could be explained by means of this PTM that suggest a similar role. Interestingly, all the enzymes involved in SUMOylation have been identified in E. histolytica (Bosch and Siderovski, 2013 ). This allows us to propose that EhTRF-like I could have similar PTMs as TRF-1 to modulate its activity and protect telomeric DNA.…”

Section: Discussionmentioning

confidence: 99%

Telomeric Repeat-Binding Factor Homologs in Entamoeba histolytica: New Clues for Telomeric Research

Rendón-Gandarilla

Álvarez-Hernández

Castañeda-Ortiz

et al. 2018

Front. Cell. Infect. Microbiol.

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Telomeric Repeat Binding Factors (TRFs) are architectural nuclear proteins with critical roles in telomere-length regulation, chromosome end protection and, fusion prevention, DNA damage detection, and senescence regulation. Entamoeba histolytica, the parasite responsible of human amoebiasis, harbors three homologs of human TRFs, based on sequence similarities to their Myb DNA binding domain. These proteins were dubbed EhTRF-like I, II and III. In this work, we revealed that EhTRF-like I and II share similarity with human TRF1, while EhTRF-like III shares similarity with human TRF2 by in silico approach. The analysis of ehtrf-like genes showed they are expressed differentially under basal culture conditions. We also studied the cellular localization of EhTRF-like I and III proteins using subcellular fractionation and western blot assays. EhTRF-like I and III proteins were enriched in the nuclear fraction, but they were also present in the cytoplasm. Indirect immunofluorescence showed that these proteins were located at the nuclear periphery co-localizing with Lamin B1 and trimethylated H4K20, which is a characteristic mark of heterochromatic regions and telomeres. We found by transmission electron microscopy that EhTRF-like III was located in regions of more condensed chromatin. Finally, EMSA assays showed that EhTRF-like III forms specific DNA-protein complexes with telomeric related sequences. Our data suggested that EhTRF-like proteins play a role in the maintenance of the chromosome ends in this parasite.

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Structural Determinants of Ubiquitin Conjugation in Entamoeba histolytica

Cited by 16 publications

References 44 publications

Extensive transcriptome analysis correlates the plasticity of Entamoeba histolytica pathogenesis to rapid phenotype changes depending on the environment

Extensive transcriptome analysis correlates the plasticity of Entamoeba histolytica pathogenesis to rapid phenotype changes depending on the environment

Stress granule formation inEntamoeba histolytica: cross-talk between EhMLBP, EhRLE3 reverse transcriptase and polyubiquitinated proteins

Telomeric Repeat-Binding Factor Homologs in Entamoeba histolytica: New Clues for Telomeric Research

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