Figure 5.

Stability of RNAs. ³²P-labeled transcripts of U3 snoRNA, U6 snRNA that was capped (U6) or uncapped (U6⁻) or a 40-nt control RNA were injected into oocyte nuclei; the RNAs were isolated and analyzed by gel electrophoresis as previously described (Lange et al., 1999). The first four lanes show the controls (0 h: sample recovery immediately after injection), the middle lanes show the RNA recovered at 4 h, and the lanes at the right show long-term stability assayed at 24 h after injection. To determine the stability of the various RNAs after nuclear injection, U2 snRNA transcripts were coinjected and served as an internal control to normalize for any differences in injection or recovery of the samples. The relative RNA stability was calculated as the ratio of a given RNA transcript to the U2 control at 4 h or 24 h compared with the 0-h control ratio [(RNA transcript/U2 after incubation)/(RNA transcript/U2 at 0 h)].