FIG. 6.

Spt5 CTD T1A and P2A mutations sensitize fission yeast to growth inhibition by 6-azauracil. Exponentially growing cultures of S. pombe strains with the indicated rbp1 and spt5 genotypes were adjusted to an A₆₀₀ of 0.1, and aliquots (3 μl) of serial 5-fold dilutions were spotted on synthetic agar medium lacking uracil and containing 6 mM NH₄OH and 0, 200, or 300 μg/ml 6-azauracil (6-AU) as specified. The plates were incubated at 30°C for 4 days (no 6-AU), 5 days (200 μg/ml 6-AU), or 5.5 days (300 μg/ml 6-AU).