Strong nucleosomes of yeasts.
Edward N Trifonov1, Vijay Tripathi1
1a Genome Diversity Center, Institute of Evolution , University of Haifa , Mount Carmel, Haifa 3498838 , Israel.
Journal of Biomolecular Structure & Dynamics
|April 21, 2015
Summary
Yeast genomes generally lack strong nucleosome (SN) sequences, but some SNs associate with centromeres, unlike in plants and animals. Candida albicans is a notable exception, showing no centromeric SN affinity.
Area of Science:
- Genetics
- Molecular Biology
- Chromatin Structure
Background:
- Strong nucleosomes (SNs) with a (RRRRRYYYYY)n consensus are found in plants and animals.
- Yeast genomes typically lack these visibly periodic SN sequences.
Purpose of the Study:
- To investigate the presence and centromeric association of SN sequences in various yeast species.
- To identify exceptions to general patterns of SN distribution in eukaryotic genomes.
Main Methods:
- Bioinformatic analysis of yeast genomes.
- Sequence comparison with known SN consensus patterns.
- Assessment of sequence distribution relative to centromeric regions.
Main Results:
- Most analyzed yeast species (Schizosaccharomyces pombe, Saccharomyces cerevisiae, Cryptococcus neoformans) show SN sequences with centromere preference, similar to higher eukaryotes.
- Candida albicans is an exception, with SNs lacking centromeric or pericentromeric affinity.
- Three out of four yeast genomes analyzed possess unique, repeating, centromere-specific SN sequences.
Conclusions:
- Centromeres across plants, animals, and most yeasts share a specialized chromatin structure that favors SNs.
- Candida albicans represents a unique evolutionary path regarding centromeric SNs.
- The findings highlight conserved and divergent mechanisms of centromere organization in eukaryotes.
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