Figure 4.

Alignment of the deduced C. parasitica BDM-1 amino acid sequence (GenBank accession no. AF140555) with that of human retinal phosducin (SWISS PROT accession no. P20941). This alignment was completed by using genetyx-mac, version 8.0 (Software Development, Tokyo). Identical amino acids are indicated in bold and with an asterisk, whereas chemically similar amino acids are marked with a dot. Clusters of sequence homology discussed in the text (BDM-1 residues 83–95, 188–205, and 247–261) are marked by dashed lines. The 11-amino acid peptide, TGPKGVINDWR, absolutely conserved in all mammalian phosducins is located within the N-terminal homology cluster spanning BDM-1 residues 83–95. Ser-73 of human phosducin, a substrate for protein kinase A, is boxed. The BDM-1 sequence contains two protein kinase A consensus motifs (R/K-X-X-S/T) that are underlined, with the potential phosphorylation sites indicated with wedges. Phosducin residues that contact Gβ are indicated below the phosducin sequence by a + (24).