Figure 2.—

Constitutive expression of histone H3 from a cell-cycle-independent promoter (Δ16H3) suppresses the GAL-MYC-cse4^K16R ctf phenotype. (A) Wild-type strains containing a GAL vector (YMB6108) or expressing GAL-MYC-cse4^K16R (YMB6110) were transformed with vector or histone constructs H2A-H2B (pAB95), H3-H4 (pAB157), H4 (pAB203), H3 (pAB204), Δ16H3N*H4 (pAB221), or Δ16H3C*H4 (pAB224) (integrated in the genome at the LEU2 locus), which constitutively express histones from a mutant promoter (Δ16), and were plated on SC limiting adenine with 2% galactose/raffinose. Fold increase in the percentage of colonies that are least half red for GAL-MYC-cse4^K16R relative to a wild-type strain with the same integrated histone construct is plotted. The results represent an average of two independent experiments with variation of <5%. (B) The GAL-MYC-cse4^K16R ctf phenotype is not suppressed by 2μ H3-H4. A reporter strain expressing 2μ H3-H4 (YMB6138) was transformed with a GAL vector, GAL-MYC-CSE4, or GAL-MYC-cse4^K16R and plated on SC −URA with limiting adenine and 2% galactose/raffinose or 2% glucose. The ctf phenotype was quantified as described in Figure 1A. Values represent the average and standard deviation of chromosome loss for three transformants.