Figure 5.

Efg1 depletion leads to a defect in A₀, A₁ and A₂ cleavages. (A) WT BY4741 and GAL::3HA::EFG1 strains were shifted from a galactose to a glucose medium. Samples were collected before and at different times after the nutritional shift. Total RNAs were extracted from these cell samples, and the accumulation of the different pre-rRNAs, rRNAs and sn(o)RNAs was analyzed by northern blot using different probes. (B) Pulse-chase labeling of RNAs. WT BY4741 and GAL::3HA::EFG1 cells were grown in galactose containing medium and were next shifted to glucose for 3 h. Cells were then pulse labeled with [2,8–³H] adenine for 2 min. Samples were collected 0, 1, 2, 5, 10, 20 and 30 min after addition of an excess of cold adenine. Total RNAs were extracted from these samples, separated by gel electrophoresis and transferred to a nylon membrane.