Fig. 1. Amino-acid sequences and domain organization MAGI-3. (A) Amino-acid sequence of rat MAGI-3. (B) Schematic organization. MAGI-3 contains six PDZ domains, as well as two WW domains and a guanylate kinase domain (GUK), which are located between the first and second PDZ domains. This organization is similar for all members of the MAGI family and is distinct from the original MAGUK proteins that contain an SH3 domain instead of the WW domains and in which the GUK domain is located at the C-terminal end of the protein.