A single circular chromosome yeast

Subtelomeres as Specialized Chromatin Domains

“…In parallel, several potentially impactful resources have been made available to study the long‐term dynamics of subtelomeres. Experimental evolution [ 73 ] of a bacterial strain with artificially engineered linear chromosomes [ 74 ] or of a budding yeast strains possessing a single circular or linear chromosome [ 75,76 ] could help understanding the causal agents and dynamics of subtelomeric emergence as well as the influence of having subtelomeres on the overall genome dynamics. Similarly, evolution experiments comparing histone point mutants lacking certain histone marks—such as H2AS129ph in budding yeast—could test the contribution of chromatin to the rapid evolution of subtelomeric regions.…”

Cdc13 is predominant over Stn1 and Ten1 in preventing chromosome end fusions

“…Our previous study showed that a lack of telomerase in SY14 led to senescence and the generation of survivors, whose telomere structures were distinguished from those of canonical Type I and Type II survivors ( Shao et al, 2019a ). This phenotype brought to mind the notion that the eroded chromosome ends of SY14 tlc1 Δ cells might also fuse together.…”

“…The single-linear-chromosome yeast strain SY14 and the single-circular-chromosome yeast strain SY15 were generated through CRISPR-Cas9-mediated successive chromosome fusions ( Shao et al, 2019a ; Shao et al, 2018 ; Shao et al, 2019b ; Figure 1A ). To examine whether the SY14 and SY15 strains can perpetually maintain their self-renewal capability, we streaked several clones of the SY14 and SY15 strains on YPD plates 63 times at intervals of two days ( Figure 1B and C ).…”

“…The physical and functional interactions between telomeres seem to complicate the study of telomere structure and function. Recently, we successfully constructed single-chromosome yeast strains, SY14 and SY15, which contain two or no telomeres, respectively ( Shao et al, 2019a ; Shao et al, 2018 ). In this work, we have taken advantage of these single-chromosome yeast strains to elucidate telomere-associated processes, some of which might be difficult to observe in yeast with multiple chromosomes.…”

“…We recently successively fused the 16 chromosomes of budding yeast via a CRISPR-Cas9 method ( Shao et al, 2019b ) and created single-chromosome yeast strains, designated SY14 and SY15, which contain a single linear or circular chromosome, respectively ( Shao et al, 2019a ; Shao et al, 2018 ). We have utilized these strains to revisit telomere-associated processes and made several intriguing findings that could never have been revealed in multiple-chromosome yeast.…”