Figure 3

Statistical analysis of miRNA population. A) A rarefaction curve of the total number of reads generated by pyrosequening versus the total number of miRNA species identified is shown. The steep curve levels off towards an asymptote, which indicates the point where additional sampling will not yield new miRNAs. The stable value of 198 miRNAs validated our sampling methodology. B) Homogeneity of the ZF miRNA population was assessed using population statistics and by determining the Chao1 diversity estimator. The Chao1 reached a mean stable value of 207, with lower and upper limits of 200.37 to 229.66, respectively, for a level of confidence of 95%. The data indicates that the 198 miRNAs identified by pyrosequencing (173 known plus 25 new) plus 19 missed miRNAs (identified by Sanger sequencing), (total = 217 miRNAs) are near the upper limit of expected ZF miRNAs present in the pyrosequencing data set.