Fig. 2.

Phenotypes of as1-1 and as2-1 mutants of A. thaliana in the presence of berberine. A Typical phenotypes of as1-1 and as2-1 plants grown in the absence (a, b) and the presence of 20 μM berberine (c, d, e, f). (a, c, e) as1-1 plants, (b, d, f) as2-1 plants. (e, f) Enlarged filamentous (e) and trumpet-like (f) leaves are seen in panels (c) and (d), respectively. Red arrowheads on as1-1 and as2-1 plants show filamentous leaves. A yellow arrowhead indicates a trumpet-like leaf. Scale bars = 1 mm in (a) to (d), 0.5 mm in (e) and (f). B as1-1 FILp:GFP (a, c), and as2-1 FILp:GFP plants (b, d) were grown on medium without and with 20 μM berberine for 18 days. Transverse sections of leaves are shown. Green signals from GFP; red, autofluorescence. Scale bars = 100 μm. C Changes in transcription levels of genes involved in the maintenance of shoot apical meristem and leaf adaxial–abaxial polarity in A. thaliana. RNA was extracted from 14-day-old shoots of WT, as1-1, or as2-1 plants. Each value was normalized by reference to the level of TUA3 transcripts. Error bars show standard deviations (n = 3). Values indicated by dashed lines are shown relative to the values for WT plants treated with 0 μM berberine. An asterisk indicates over a twofold significant increase from each plant not treated with berberine (p < 0.01 by Student’s T test)