A severe clf allele carries a point mutation in the SET domain. (A) Alignment of a part of the SET domains of different SET domain proteins; residues conserved in all proteins are shaded, residue R794 that is mutated to H in clf-81 is marked. (B) clf-81 shows leaf curling and early flowering (compare to wild-type Ws (Wassilewskija)), similar to the clf-50 deletion allele. (C) clf-50 is complemented by a 35S∷GFP-CLF transgene but only partially by a 35S∷CLF-GFP transgene. All plants were grown under short day conditions; scale bar is 1 cm. AtCLF, Arabidopsis thaliana CURLY LEAF; AtSWN, A. thaliana SWINGER; DmE(z), Drosophila melanogaster ENHANCER OF ZESTE; SpCLR4, Schizosaccharomyces pombe CLR4; HsSET7/9, Homo sapiens SET7/9.