Examples of co-regulated microRNAs. (a) MicroRNAs with a sharp peak at the E12.5 stage. Methods were as described for Figure 3. Brackets indicate closely related sequences. (b) MicroRNAs with a single sharp peak at the adult stage. (c) Co-regulation of microRNAs derived from the mir-17 cluster from chromosome 14. To compare signal intensities, data were transformed to give a mean of 0 and a standard deviation of 1.