Sequence alignment of Puf domains (8 imperfect repeats) in selected Puf proteins. (A) Sequences were from T.gondii (TgPuf1), P.falciparum (PfPuf1), D.melanogaster (DmPumilio, CAA44474.1), Homo sapiens (HsPUM1, NP 001018494.1), S.cerevisiae (ScPuf3p, NP 013088.1) and C.elegans (CePuf9, NP 508980.2). Identical amino acids are highlighted in black and similar residues are shown in pink and blue (less similar). * indicates amino acids that are putative RNA contact sites. (B) Sequence alignment of amino acid triplets at the positions 12, 13 and 16 in each Puf repeat (R1 to R8).