Targeted Disruption of an EH‐domain Protein Endocytic Complex,Pan1‐End3

Pan1 is a multi‐domain scaffold that enables dynamic interactions with both structural and regulatory components of the endocytic pathway. Pan1 is composed of Eps15 Homology (EH) domains which interact with adaptor proteins, a central region that is responsible for its oligomerization and C‐terminal binding sites for Arp2/3, F‐actin, and type‐I myosin motors. In this study, we have characterized the binding sites between Pan1 and its constitutive binding partner End3, another EH domain containing endocytic protein. The C‐terminal End3 Repeats of End3 associate with the N‐terminal part of Pan1's central coiled‐coil region. These repeats appear to act independently of one another as tandem, redundant binding sites for Pan1. The end3‐1 allele was sequenced, and corresponds to a C‐terminal truncation lacking the End3 Repeats. Mutations of the End3 Repeats highlight that those residues which are identical between these repeats serve as contact sites for the interaction with Pan1.