Figure 5.

Localization of UNI Transcripts in Wild-Type, tl, af, and af tl Mutant Samples by RNA in Situ Hybridization on Transverse Sections.

Sections taken from 2-week-old seedlings hybridized with an antisense digoxigenin-labeled UNI probe.

(A) Wild type (JI 1194).

(B) tl mutant (JI 1197).

(C) and (D) af mutant (JI 1195).

(E) and (F) af tl double mutant (JI 1199).

White arrowheads in (A) and (B) indicate lateral primordia on P3 and P4 marginal blastozones where transcripts were not detected. The black arrowheads in (C) to (E) indicate secondary lateral blastozones on P3, P4, and P5 primary blastozones where UNI transcripts were detected. White arrowhead in (D) indicates a tertiary primordium in which UNI expression was downregulated compared with the expression in an adjacent secondary blastozone (marked with a black arrowhead). Black arrowheads in (F) indicate tertiary blastozones where UNI transcripts were detected. (A) to (C) and (E) were taken ∼40 μm below the shoot apex; (D) and (F) were taken ∼70 μm above the shoot apex. A, vegetative shoot apex; P2 to P5, plastochronic age of leaf primordia; S3 to S6, stipule primordia present on P3 to P6 marginal blastozones.