Spatial inter-centromeric interactions facilitated the emergence of evolutionary new centromeres
- Jawaharlal Nehru Centre for Advanced Scientific Research, India
- Nanyang Technological University, Singapore
- University College Dublin, Ireland
- Conway Institute, University College Dublin, Ireland
Abstract
Centromeres of Candida albicans form on unique and different DNA sequences but a closely related species, Candida tropicalis, possesses homogenized inverted repeat (HIR)-associated centromeres. To investigate the mechanism of centromere type transition, we improved the fragmented genome assembly and constructed a chromosome-level genome assembly of C. tropicalis by employing PacBio sequencing, chromosome conformation capture sequencing (3C-seq), chromoblot, and genetic analysis of engineered aneuploid strains. Further, we analyzed the 3D genome organization using 3C-seq data, which revealed spatial proximity among the centromeres as well as telomeres of seven chromosomes in C. tropicalis. Intriguingly, we observed evidence of inter-centromeric translocations in the common ancestor of C. albicans and C. tropicalis. Identification of putative centromeres in closely related Candida sojae, Candida viswanathii and Candida parapsilosis indicates loss of ancestral HIR-associated centromeres and establishment of evolutionary new centromeres (ENCs) in C. albicans. We propose that spatial proximity of the homologous centromere DNA sequences facilitated karyotype rearrangements and centromere type transitions in human pathogenic yeasts of the CUG-Ser1 clade.
Data availability
All sequencing data reported in the study and the genome assembly of C. tropicalis and C. sojae have been submitted to NCBI under the BioProject accession numbers PRJNA596050 and PRJNA604451
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Candida tropicalis and Candida sojaeNCBI Bioproject, PRJNA596050.
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Whole genome sequencing of Candida tropicalis isolatesNCBI Bioproject, PRJNA604451.
Article and author information
Author details
Funding
Council of Scientific and Industrial Research (Shyama Prasad Mukherjee Fellowship 07/733(0181)/2013-EMR-I)
- Krishnendu Guin
Department of Biotechnology , Ministry of Science and Technology (BT/PR27490/Med/29/1323/2018)
- Kaustuv Sanyal
Ministry of Education - Singapore (RG39/18)
- Amartya Sanyal
Department of Biotechnology , Ministry of Science and Technology
- Kaustuv Sanyal
Nanyang Technological University (Nanyang Assistant Professorship grant)
- Amartya Sanyal
Department of Biotechnology , Ministry of Science and Technology
- Kaustuv Sanyal
Department of Biotechnology , Ministry of Science and Technology
- Kaustuv Sanyal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Guin 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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Spatial inter-centromeric interactions facilitated the emergence of evolutionary new centromeres
eLife 9:e58556.
https://doi.org/10.7554/eLife.58556
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