Figure 3.

Northern blot analyses of the reduction of ntl mRNA and the presence of ribozyme in the pT7vaRz(ntl)₄₃₅-injected zebrafish embryos. Fertilized zebrafish eggs were injected with pT7vaRz(ntl)_435, pT₇T₇, and T7 RNA polymerase as described in Fig. 2. Total RNA was isolated from 50 injected and uninjected embryos at 5.2, 12, and 24 h postfertilization. Each RNA sample (8 μg) was subjected to electrophoresis in a 1% agarose–formaldehyde gel. After gel transfer, the membrane containing the transferred RNAs was hybridized with appropriate probes as described in Materials and Methods. (A) Northern blot with the ntl probe. Rz, RNA isolated from the injected embryos; C, RNA isolated from uninjected embryos. (B) The same membrane rehybridized with ribozyme and actin probes. The actin mRNAs serve as the internal RNA quantitation references for each time point.