Genome duplication in Leishmania major relies on persistent subtelomeric DNA replication
Abstract
DNA replication is needed to duplicate a cell's genome in S-phase and segregate it during cell division. Previous work in Leishmania detected DNA replication initiation at just a single region in each chromosome, an organisation predicted to be insufficient for complete genome duplication within S-phase. Here, we show that acetylated histone H3 (AcH3), base J and a kinetochore factor colocalise in each chromosome at only a single locus, which corresponds with previously mapped DNA replication initiation regions and is demarcated by localised G/T skew and G4 patterns. In addition, we describe previously undetected subtelomeric DNA replication in G2/M and G1 phase-enriched cells. Finally, we show that subtelomeric DNA replication, unlike chromosome-internal DNA replication, is sensitive to hydroxyurea and dependent on 9-1-1 activity. These findings indicate that Leishmania's genome duplication programme employs subtelomeric DNA replication initiation, possibly extending beyond S-phase, to support predominantly chromosome-internal DNA replication initiation within S-phase.
Data availability
Sequences used in this study have been deposited in the European Nucleotide Archive. Data can be accessed using the accession number PRJEB35027.
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Genome duplication in Leishmania major relies on unconventional subtelomeric DNA replicationEuropean Nucleotide Archive, PRJEB35027.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/N016165/1)
- Luiz R O Tosi
- Richard McCulloch
Biotechnology and Biological Sciences Research Council (BB/R017166/1)
- Richard McCulloch
European Commission (RECREPEMLE)
- Jeziel Dener Damasceno
Wellcome (104111)
- Richard McCulloch
Medical Research Council (MR/S019472/1)
- Jeziel Dener Damasceno
- Richard McCulloch
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Christine Clayton, DKFZ-ZMBH Alliance, Germany
Version history
- Received: April 17, 2020
- Accepted: September 7, 2020
- Accepted Manuscript published: September 8, 2020 (version 1)
- Version of Record published: September 23, 2020 (version 2)
Copyright
© 2020, Damasceno 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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