Modifications at K31 on the lateral surface of histone H4 contribute to genome structure and expression in apicomplexan parasites
Abstract
An unusual genome architecture characterizes the two related human parasitic pathogens Plasmodium falciparum and Toxoplasma gondii. A major fraction of the bulk parasite genome is packaged as transcriptionally permissive euchromatin with few loci embedded in silenced heterochromatin. Primary chromatin shapers include histone modifications at the nucleosome lateral surface close to the DNA but their mode of action remains unclear. We now identify versatile modifications at Lys31 within the globular domain of histone H4 that crucially determine genome organization and expression in Apicomplexa parasites. H4K31 acetylation at the promoter correlates with, and perhaps directly regulates, gene expression in both parasites. In contrast, monomethylated H4K31 is enriched in the core body of T. gondii active genes but inversely correlates with transcription while being unexpectedly enriched at transcriptionally inactive pericentromeric heterochromatin in P. falciparum, a region devoid of the characteristic H3K9me3 histone mark and its downstream effector HP1.
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Funding
European Commission (ERC Consolidator Grant No. 614880)
- Fabien Sindikubwabo
- Dominique Cannella
- Mohamed-ali Hakimi
European Commission (ERC AdG No. 670301)
- Artur Scherf
Agence Nationale de la Recherche (ANR-10-INBS-08-01)
- Lucid Belmudes
- Yohann Couté
Agence Nationale de la Recherche (LABEX PARAFRAP ANR-11-LABX-0024)
- Fabien Sindikubwabo
- Shuai Ding
- Tahir Hussain
- Dominique Cannella
- Andrés Palencia
- Alexandre Bougdour
- Cyrille Y Botté
- Artur Scherf
- Mohamed-ali Hakimi
Agence Nationale de la Recherche (ANR-12-BSV3-0009-01)
- Dominique Cannella
- Andrés Palencia
- Alexandre Bougdour
- Mohamed-ali Hakimi
Agence Nationale de la Recherche (ANR-12-PDOC-0028)
- Cyrille Y Botté
CNRS-INSERM-Fondation FINOVI (Atip-Avenir Program Project Apicolipid)
- Cyrille Y Botté
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Sindikubwabo et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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