Shuffling the yeast genome using CRISPR/Cas9-generated DSBs that target the transposable Ty1 elements
Fig 7
Breakpoints within Ty elements as determined by Nanopore sequencing.
Since Ty elements often have polymorphisms that distinguish different elements, we can sometimes determine the breakpoints within the Ty elements involved in homologous recombination. These Ty-Ty recombination events sometimes involve elements located on non-homologous chromosomes (giving rise to translocations; A, E, H, and K) or elements located on the same chromosome (giving rise to I-DEL, I-DUP or other rearrangements; B, C, D, F, G, I, and J). The position of the target guide RNA is indicated by an arrow marked “DSB” and different colors represent sequences derived from different elements. In some of the recombination events (C, G, I, and J), the breakpoint between the contributions of the different Ty elements to the recombinant element is near the DSB site. In most of the other events, the transition between the different Ty elements does not coincide exactly with the DSB site. In these cases, it is likely that the repair of the DSB was associated with a gene conversion event. Lastly, one of the isolates (K) was associated with a tripartite recombination event between Ty elements located on three different chromosomes as illustrated in S24 and S25 Figs.