Xenopus limk1 mRNA as a potential target of miR-134. (A-B) Representative confocal double FISH images showing growth cones subjected to either reverse Xlimk1 probes and scrambled miRNA probes (A) or Xlimk1 probes and LNA-miR-134 probes (B). Color panels are the merged channels of both Xlimk1 (green) and miR-134 (red) signals, of which an intensity threshold was applied to each channel to highlight the FISH signals. Yellow colors indicate co-localization of Xlimk1 and miR-134. Scale bars: 10 μm. (C) Quantification of the percentage of Xlimk1 puncta co-localized with miR-134 puncta. Numbers indicate the number of growth cones examined. (D) The predicted duplex formation between miR-134 (red) and Xlimk1 (green) 3'UTR is shown on the left (optimal binding energy: -28.2 kcal/ml). The results of luciferase assays using a Xlimk1 3'UTR-luciferase reporter are shown in the bar graph on the right. Numbers indicate the total numbers of samples from three repeated trials. Error bars depict the standard error of the mean. Asterisks in (C & D): p < 0.01 Student's t-test.