Figure 1.

Cloning frequency and conservation for all miRNAs cloned from zebrafish small-RNA cDNA libraries. The upper panel depicts the cloning frequency for all small RNAs that were found in the two libraries and that passed our computational pipeline. All 139 known miRNAs (blue data points) were cloned more than once, while 37 out of the 66 new miRNAs (pink dots) were represented by a single sequenced clone. The lower panel shows a scatter plot of the conservation of known (blue dots) and new (pink data dots) miRNAs in 12 vertebrate species (zebrafish, fugu, tetraodon, mouse, rat, human, dog, macaca, opossum, chicken, chimpanzee, cow). Forty-four of the new miRNAs were only found in zebrafish, while most of the known miRNAs were found in several species according to our conservation criteria.