Figure 3.

In vitro miRNA degradation assays. RNA oligos (1.0 µg per lane) were incubated with RNase-containing extracts (10 µg protein per reaction) prepared from cells in and around the stem cambial zone of greenhouse-grown P. trichocarpa at 25°C for 0, 10, 20, 40 and 80 min, respectively, and then separated on a 15% denaturing polyacrylamide gel (A–C). Reactions without the addition of RNA oligos were used as controls (A). The level of nondegraded miRNAs after incubation was quantitated by the real-time PCR method as previously described (18). Levels of miRNA from reactions incubated for 0 min were arbitrarily set to 1. The data are means of three measurments ± SD (D–F).