Evidence map›Paper›PMID 41915685›Full record

ArticlePLoS pathogens2026

New Histone H4 variant and H2B variant Exhibits distinct genomic distributions, chromatin affinities, and dynamics throughout life and cell cycle of Trypanosoma cruzi.

Juliana Nunes Roson, Mariana Loterio-Silva, Herbert Guimaraes de Sousaes Silva, Thaina Rodrigues de Almeida, Nadjania Saraiva de Lira Silva, Camila Gachet-Castro, Héllida Marina Costa-Silva, Vincent Louis Viala, Sergio Schenkman, M Carolina Elias and 1 more

Abstract read
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Article in PLoS pathogens, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

11 authors.

Juliana Nunes RosonLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Mariana Loterio-SilvaLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Herbert Guimaraes de Sousaes SilvaLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Thaina Rodrigues de AlmeidaLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Nadjania Saraiva de Lira SilvaDepartment of Microbiology, Immunology, and Parasitology, Escola Paulista de Medicina - UNIFESP, São Paulo, Brazil.
Camila Gachet-CastroLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Héllida Marina Costa-SilvaLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Vincent Louis VialaBiochemistry Laboratory, Butantan, Institute, São Paulo, Brazil.
Sergio SchenkmanDepartment of Microbiology, Immunology, and Parasitology, Escola Paulista de Medicina - UNIFESP, São Paulo, Brazil.
M Carolina EliasLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.
Julia P C da CunhaLaboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil.ORCID https://orcid.org/0000-0003-0466-8879

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Histone variants play crucial roles in chromatin organization and transcriptional regulation in eukaryotes. Unusually, trypanosomatids display histone variants for all histones, although a functional homolog of histone H4 variant (H4.V) had not yet been described in Trypanosoma cruzi. In this study, we identified a H4.V in T. cruzi that is encoded by a single-copy gene located apart from the typical tandem arrays of canonical histone H4. Functional characterization using ChIP-seq assays revealed that H4.V is located at telomere-subtelomere interface, demarcates convergent strand-switch regions (cSSRs), and determines potential new transcription termination sites at codirectional PTUs interrupted by tDNA loci. Throughout the cell cycle, H4.V abundance increases in G2/M, as shown by immunofluorescence and imaging flow cytometry. In contrast, the histone H2B variant (H2B.V) abundance accumulates progressively. H4.V is more abundant in the nuclei of metacyclic trypomastigotes but barely detectable in amastigotes and bloodstream trypomastigotes. In contrast, H2B.V shows a punctate nuclear pattern and is present in all life stages, with the highest levels also observed in metacyclics. During metacyclogenesis, both variants show a progressive increase in expression, particularly H4.V, suggesting a role in parasite differentiation. Ultimately, salt extraction experiments revealed life stage-dependent differences in histone distribution profiles, particularly between insect-stage and mammalian-stage parasites, with H4.V displaying greater retention in the salt-resistant chromatin fraction, whereas H2B.V was more readily released under low-salt conditions compared to canonical histone H3. Our data reveal H4.V as a novel histone variant in T. cruzi, characterized by unique genomic localization, expression profiles, and chromatin-binding dynamics in contrast to H2B.V. These findings underscore H4.V as a marker associated with transcriptional termination, and possibly contributing to metacyclogenesis or vector-stage adaptation.

Indexed as

Cell CycleChromatinHistonesProtozoan ProteinsTrypanosoma cruziAnimalsLife Cycle StagesChromatinHistonesProtozoan Proteins

Identifiers

PMID41915685
PMCPMC13052989

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