Fig. 4: Comparison of Fat4:Dchs1, cadherin, and protocadherin structures.
From: Structure of the planar cell polarity cadherins Fat4 and Dachsous1
a Comparison of the Fat4:Dchs1 structure with structures of selected protocadherin homodimers, the E-cadherin homodimer, and the PCDH15:CDH23 heterodimer. The buried surface area and dissociation or homodimerization constants for each interaction are indicated beneath the structures. b The EC3-EC4 domains of Fat4 or Dchs1 and several protocadherins were aligned to highlight the tilted orientation of Fat4(EC1) and Dchs1(EC1). c Zoom panels showing distinctive structural features in Fat4 or Dchs1 domains. Upper-left: an insertion within the β1 loop of Fat4(EC4) contacts Dch1(EC1). Upper-right: Dchs1(EC1) has less secondary structure content than protocadherin EC1 domains. Bottom-left: the connecting loop between β3 and β4 of Fat4(EC3) is truncated and does not interact with Dchs1(EC2). Bottom-right: a R387 residue in Dchs1(EC4) is not conserved in protocadherins and makes substantial contacts with Fat4(EC1).
