Fig. 1.
URA3 supports cohesion. (A) Schematic of experimental protocol. ROI, region of interest. Half-filled boxes represent RS sites for the R site-specific recombinase. Fluorescence micrographs of strain JSC97 are provided. Two large-budded, M phase-arrested cells are shown, one with a single focus of GFP-lacI fluorescence and the other with two foci of GFP-lacI fluorescence (red arrows). (B) Schematic of the constructs used. (C) Cohesion measurements. Strains MSB7 (URA3f) and MSB13 (empty) were arrested in M phase by Cdc20 depletion, whereas JSC97 (URA3r) was arrested with nocodazole (+NZ). Nicotinamide (NAM; final concentration, 2 mM) was added to half of the JSC97 culture 2 h after DNA circularization, and cells were harvested 2 h later. N denotes the number of cells examined. P values for pairwise χ2 tests are presented relative to a benchmark strain designated with a dash.