Loss-of-function mutations of FBW2 suppress the phenotype of sqn-1. (A) An 18-day-old rosettes of wild-type (WT), fbw2-1, sqn-1, sqn-1 fbw2-1, sqn-1 fbw2-4 and sqn-1 fbw2-1 plants containing a genomic pFBW2::FBW2-FLAG construct. Rosettes are same magnification. (B) Leaf shape of successive juvenile (light grey) adult (dark grey) and cauline leaves (black) in WT, fbw2-1, sqn-1 and sqn-1 fbw2-1 plants. Juvenile leaves were defined by the absence of abaxial trichomes (n = 24; ± standard deviation). (C) Relative abundance of miRNA targets in various genotypes as measured by quantitative-real time polymerase chain reaction. Target genes were normalized to EIF4. Actin was used as a non-target control (± standard deviation). (D) The genomic structure of FBW2 and the amino acid changes produced by fbw2-1, fbw2-2 and fbw2-3. The locations of the T-DNA insertions in fbw2-4 (SALK_144548) and fbw2-5 (SALK_071588) are also illustrated.