Figure 3

rps10b-1 suppresses some auxin-related phenotypes of max2-1. (a) Growth and auxin sensitivity of cauline axillary buds in isolation from the plant. Single cauline nodes with a bud smaller than 2 mm were excised from sterile plants and inserted between two agar slabs in a Petri dish. Time course of bud elongation in the absence (solid lines, Control) and in the presence of synthetic auxin (1-naphthaleneacetic acid at 1 μM added to the apical agar slab, dashed lines, NAA). Average ± SEM, n = 12– 20. (b) Polar auxin transport along 1.5 cm stem segments from the base of the primary inflorescence of 6-week-old plants. 1 μM ¹⁴C-IAA was in contact with the apical end of the segment without (black bars) or with the polar auxin transport inhibitor naphthylphtalamic acid (NPA, at 1 μM, white bars) for 6 hours. The mean radioactivity extracted from the basal 5 mm of the segments ± SEM is shown (n = 23–24 minus NPA, n = 9-10 plus NPA). (c-j) Activity of the auxin response reporter DR5::GUS in hypocotyls. Hypocotyls were stained for GUS activity (blue), fixed, embedded, sectioned at 10 μm, and counterstained with ruthenium red. (c-f) Hypocotyl sections from 2-week-old seedlings grown in continuous light. (g-j) Hypocotyl sections from 9-week-old plants grown in short photoperiods. Scale bar in (c) for (c-f) and in (g) for (g-j) 100 μm.