Back to article: Guidelines for DNA recombination and repair studies: Cellular assays of DNA repair pathways
FIGURE 5. Assays to study gross chromosomal rearrangements. (A) Diagram of the uGCR, dGCR, and sGCR assays depicting the position of the CAN1/URA3 counter-selectable cassette (white box labeled “C/U”) relative to the DSF1-HXT13 segmental duplication (grey box labeled “D-H”), and the most telomeric essential gene PCM1 (white box labeled “P”). The grey region of the chromosome corresponds to the breakpoint region, which lies between PCM1 and the CAN1/URA3 cassette and is the region where one of the breaks associated with the GCR must occur. The grey box in the sGCR assay corresponds to a region of short homology containing a repetitive tRNA and ∼100 bp of a repetitive delta sequence. (B) Selection of GCR assay-containing strains for resistance to 5-fluoroorotic acid (5-FOA) and canavanine (Can) selects for strains in which one of a number of GCRs has formed; these types of GCRs are selected at different rates in the different GCR assays. White chromosomes indicate translocations to other chromosomes (or alternatively different regions of the assay chromosomes).