Fig. 1. AXR1 acts redundantly with AS1 to exclude BP expression from leaves. (A-H) Fourth rosette leaf (A,C,E,G) and scanning electron micrographs of the sinus region (B,D,F,H) of (A,B) Col, (C,D) axr1-12, (E,F) as1-1 and (G,H) as1-1;axr1-12 plants; arrowheads indicate lobe (G) and ectopic stipules (H). (I-L) Rosette leaves 1-7 of (I) Col, (J) axr1-12, (K) as1-1 and (L) as1-1;axr1-12. (M) Quantitative RT-PCR analysis of BP, STM and AS1 expression in mature leaves of Col (white bars), axr1-3 (black bars) and as1-1 (grey bars). Error bars indicate s.e.m. (N,O) Fourth rosette leaf of (N) axr1-12;bp-9 double and (O) as1-1;axr1-12;bp-9 triple mutants. (P,Q) Leaves 1-7 of (P) axr1-12;bp-9 and (Q) as1-1;axr1-12;bp-9.(R-V) Leaves stained for BP::GUS expression in (R) Col, (S) axr1-3, (T) as1-1 and (U,V) axr1-3;as1-1; arrows indicate staining in sinus regions. (R-U) Fourth leaves and (V) eighth leaf dissected from 14-day old plants. (W-Y) Scanning electron micrographs of the sinus region of (W) as1-1, (X) as1-1;axr1-12 and (Y) as1-1;axr1-12;bp-9 cauline leaves. Scale bars: 0.5 cm in A,C,E,G,N,O; 25 µm in B,D,F,H,W-Y; 1 cm in I-L,P,Q; 200 µm in R-V.