miRNA accumulation within the meristem central zone is suppressed post-transcriptionally by tuning processing efficiency. (A,B) Compared with the wild type (A), 2-wk-old dcl1-2 (B) seedlings show a weak phenotype typified by a compact stature and tightly curled leaves. (C) Global gene expression profiles for the CZ (left) and P3 primordia (right) in dcl1-2 and wild type are highly significantly correlated (r = 0.99 and r = 0.97, respectively). (D) The effect of dcl1-2 on precursor levels is far more pronounced in P3 primordia than in the CZ. The red line indicates an equal dcl1-2/WT expression ratio in the two tissues. Incidents above the red line indicate precursors with higher processing efficacy in P3 primordia.
