Figure 1.

Sequence analysis of SmAPs. A multiple sequence alignment of SmAPs is shown, along with the sequence of the most similar known Sm structure (human D₃) as a reference point (residue numbering is for the P. aerophilum sequence). Pairwise sequence similarity scores between SmAP and its homologs are provided in the last column. The top diagram depicts the SmAP monomer in terms of secondary structure elements. Glycine (yellow), acidic (red), and basic (blue) residues are highlighted in the consensus sequence and are referred to in the text and in Fig. 2c.