FIGURE 1.

Microinjected pre-miR-31 is actively exported from nuclei of Xenopus laevis oocytes. Here, 15 nL of a mixture of 10 nM pre-miR-31 and U6Δss injection control were coinjected into nuclei of stage IV–V oocytes. If indicated, RNA mixtures also included 2 μM RanGAP or 500 nM or 2 μM unlabeled pre-miR-31 (competitor). Oocytes were separated into (N) nuclear and (C) cytoplasmic fractions 30 min after injection; RNA was extracted and analyzed on a 10% denaturing PAGE gel. The dried gel was quantified by a phoshorimager, and export was expressed as the cytoplasmic:nuclear (C:N) ratio.