Regulation of miRNA hsa-miR-342-3p in different prion disorders. A. Regulation of miRNAs upon BSE infection in cynomolgus macaques compared to the published miRNA profile of Scrapie infection in mice. 500 ng miRNA enriched fraction from a BSE-infected and a non-infected rhesus macaque were fluorescently labeled and applied to miRNA microarray (Probeset 1564V1, Ambion). Regulation of each miRNA was calculated from the relative fluorescence values of the infected versus the non-infected animal. Acquired miRNA regulation profile was compared to a published profile derived from Scrapie-infected mice . Correlation of both regulation profiles was statistically significant (Spearman correlation, p < 0.05). Relevant miRNAs regulated above twofold in both arrays are marked by an open square. B. Regulation of miR-342-3p in samples derived from brains of patients with type 1 sCJD, type 2 sCJD and a healthy control, respectively. 5 ng miRNA were applied to qRT-PCR specific for hsa-miR-342-3p (stem-loop qRT-PCR, Applied Biosystems). Relative miRNA expression was analyzed by ΔΔCT method  using the small nucleolar RNA RNU48 as a housekeeping RNA and the healthy human control as a calibrator. Statistical significance was determined by student-t-test (non-parametric with Welch's correction, *** p < 0.001). The mean regulation factor ± SD of duplicates from two independent experiments are shown.