title: Affected chromosome homeostasis and genomic instability of clonal yeast cultures.
abstract: Yeast cells originating from one single colony are considered genotypically and phenotypically identical. However, taking into account the cellular heterogeneity, it seems also important to monitor cell-to-cell variations within a clone population. In the present study, a comprehensive yeast karyotype screening was conducted using single chromosome comet assay. Chromosome-dependent and mutation-dependent changes in DNA (DNA with breaks or with abnormal replication intermediates) were studied using both single-gene deletion haploid mutants (bub1, bub2, mad1, tel1, rad1 and tor1) and diploid cells lacking one active gene of interest, namely BUB1/bub1, BUB2/bub2, MAD1/mad1, TEL1/tel1, RAD1/rad1 and TOR1/tor1 involved in the control of cell cycle progression, DNA repair and the regulation of longevity. Increased chromosome fragility and replication stress-mediated chromosome abnormalities were correlated with elevated incidence of genomic instability, namely aneuploid events-disomies, monosomies and to a lesser extent trisomies as judged by in situ comparative genomic hybridization (CGH). The tor1 longevity mutant with relatively balanced chromosome homeostasis was found the most genomically stable among analyzed mutants. During clonal yeast culture, spontaneously formed abnormal chromosome structures may stimulate changes in the ploidy state and, in turn, promote genomic heterogeneity. These alterations may be more accented in selected mutated genetic backgrounds, namely in yeast cells deficient in proper cell cycle regulation and DNA repair.
authors.affiliation: Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland.
authors.forename: Jagoda
authors.initials: J
authors.lastname: Adamczyk
authors.affiliation: Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Deregowska
authors.affiliation: Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland.
authors.forename: Anita
authors.initials: A
authors.lastname: Panek
authors.affiliation: Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland.
authors.forename: Ewelina
authors.initials: E
authors.lastname: Golec
authors.affiliation: Department of Biochemistry and Cell Biology, University of Rzeszow, Zelwerowicza 4, 35-601, Rzeszow, Poland. alewinska@o2.pl.
authors.forename: Anna
authors.initials: A
authors.lastname: Lewinska
authors.affiliation: Department of Genetics, University of Rzeszow, Rejtana 16C, 35-959, Rzeszow, Poland. mawnuk@gmail.com.
authors.forename: Maciej
authors.initials: M
authors.lastname: Wnuk
mesh_terms: D000782:Aneuploidy; D015825:Chromosomes, Fungal; D055028:Comparative Genomic Hybridization; D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics; D042822:Genomic Instability; D006706:Homeostasis; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D004271:DNA, Fungal
keywords: Chromosome; Genomic instability; In situ comparative genomic hybridization; Yeast