FIGURE 4.

Alignment of the amino acid sequences of CG3362, human cNIII, and cNIII-like proteins. Amino acids constituting the catalytic motifs I, II, and III (24, 27) are shown in red and marked below the sequence. The lysine at position 268 of cytosolic nucleotidase III is also considered part of motif III (24), but the corresponding amino acid in other enzymes is not immediately obvious from the sequence. The WW or WY motif at position 152/153 of cytosolic nucleotidase III, also shown in red, is involved in binding the base of the substrate. Sequence identities are highlighted by dark gray shading, and amino acid similarities are marked by light gray shading. Protein sequences were retrieved from the PubMed server (blast.ncbi.nlm.nih.gov) (cNIII, CAG38549; cNIII-like, Q969T7; CG3362, AAF47180), and the alignment was done with MUSCLE (53) with preset restraints.