Developmental phenotype of ago1 slicer-deficient plants. A, Seedlings of Col-0 wild type, ago1-27 (hypomorphic allele), ago1-3, the complementation line of ago1-3 with wild-type AGO1P:FLAG-AGO1, and slicer-deficient point mutants D762A, E803A, D848A, and H988F. B, Rosettes of ago1-3 null and slicer-deficient mutants. C, Cauline leaves of ago1-3 null and slicer-deficient mutants. D, Flowers and aberrant reproductive organs of ago1-3 null and slicer-deficient mutants. E, Representative T1 plants of slicer-deficient (SD) AGO1P:FLAG-AGO1 in Col-0 wild type or ago1-3/+. A wide variability of defects was found among T1 plants of the four point mutants, but not in plants transformed with the equivalent wild-type transgene.