Figure 4.

Superloser reduces background associated with humanization of yeast histones. (a) Experimental setup: yDT51 with yeast histones on pDT83 (normal) or yMAH302 with yeast histones on pDT139 (Superloser) was transformed with the shuffle plasmid (pDT109) containing the human histones. 20 biological replicates of each strain were grown for 1.5 days in either SC–Trp+2%dex or SC–Trp+2%gal/1%raf, at which point cells were collected, washed, and then plated at two concentrations onto SC–Trp+5-FOA. Colonies were counted every week for 4 weeks. (b) Distribution of the number of 5-FOA^R colonies isolated per plate from shuffle experiments with yDT51 and yMAH302. (c) Example images of SC–Trp+5-FOA plates from the shuffle experiment. Growth at week 1 is compared to growth at week 4, note the density of colonies at week 1 for yDT51 vs. yMAH302. (d) Fraction of the total number of 5-FOA^R colonies isolated at each week that colonies were observed. Note that most colonies of yDT51 were isolated prior to 3 weeks of growth indicating higher background events. (e) The fraction of plates with colonies is shown at each week for yDT51 and yMAH302.