Expression of let-7a, miR-9, and miR-129-5p in the cerebellum of the human fetal brain. In all images, miRNA hybridization signals are in red (Cy3) and DAPI stained cell nuclei are in blue. (A and B) A cerebellum section hybridized with a LNA modified let-7a detection probe. Note the cytoplasmic localization of the let-7a signal. (C) A cerebellum section hybridized with a miR-9 detection probe. (D) A miR-9 probe with 4 nucleotides mutated (miR-9m) detected no hybridization signal. (E) A cerebellum section hybridized with a miR-129-5p detection probe. (F) A negative control probe with scrambled sequence detected no hybridization signal. The scale bars are 40'm in A and 20'm in B through F.