Figure 4.
None of the three exo− mutants shows induction of GRL1 mRNA following stimulation. Total RNA was isolated from wild-type and exo− mutants (SB281, MN173, and MN175) at 0 and 16 h of starvation and 60 and 240 min following stimulation. (A) Slot-blot hybridization of poly(A)+ normalized total RNA samples using a 32P-labeled GRL1 cDNA probe. Wild type shows the characteristic increase in GRL1 mRNA abundance at 60 min poststimulation. In the exo− mutants, there is no increase in GRL1 mRNA abundance following stimulation. (B) Quantitation of slot blots hybridized with the GRL1 specific probe. The patterns of mRNA abundance for both CyP and histone H4 are similar to wild type (data not shown).