Figure 3.
The YAC breakage assay. Cells containing YAC CF1 (not to scale), which has a non-B DNA-forming sequence (shown as a red star) and URA3 gene, are FOAS. If breakage occurs in the region around the non-B DNA insertion, the YAC will lose the URA3 gene, resulting in FOAR. The YAC can be rescued by addition of a yeast telomere onto the C4A4 seed sequence. Adapted from Callahan et al (112).