Fig. 4. Interaction of Kermit with the C termini of Xfzs in yeast two hybrid assays. Yeast strain Y190 was transformed with Kermit or Kermit mutants and Xfz3, Xfz7 or Xfz8, plated on either nonselective medium (-trp, -leu) or selective medium (-trp, -leu, -his). Growth was checked 3 to 4 days later, and the hydrolysis of X-gal was monitored on filter lifts from all plates. Plus signs indicate size of colonies; minus sign indicates no growth (in left and middle columns) or no X-gal hydrolysis (right column). (A) Interaction of Kermit with the C termini of Xfz3, Xfz7 and Xfz8. (B) Domain requirement of Kermit in interaction with Xfz3. Blue, N terminus (amino acids 1-127); green, PDZ domain (amino acids 128-217); purple, C terminus (amino acid 218-331).