Related Experiment Video
Updated: Aug 10, 2026

In Vitro Analysis of PDZ-dependent CFTR Macromolecular Signaling Complexes
Published on: August 13, 2012
Epsin N-terminal homology domains perform an essential function regulating Cdc42 through binding Cdc42
Rubén C Aguilar1, Silvia A Longhi, Jonathan D Shaw
1Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA.
Abstract:
Epsins are endocytic proteins with a structured epsin N-terminal homology (ENTH) domain that binds phosphoinositides and a poorly structured C-terminal region that interacts with ubiquitin and endocytic machinery, including clathrin and endocytic scaffolding proteins. Yeast has two redundant genes encoding epsins, ENT1 and ENT2; deleting both genes is lethal. We demonstrate that the ENTH domain is both necessary and sufficient for viability of ent1Deltaent2Delta cells. Mutational analysis of the ENTH domain revealed a surface patch that is essential for viability and that binds guanine nucleotide triphosphatase-activating proteins for Cdc42, a critical regulator of cell polarity in all eukaryotes. Furthermore, the epsins contribute to regulation of specific Cdc42 signaling pathways in yeast cells. These data support a model in which the epsins function as spatial and temporal coordinators of endocytosis and cell polarity.
Related Concept Videos
Catenins
Catenins in Cell Junctions
Catenins bind to cell adhesion molecules such as cadherins and link them to different cytoskeletal proteins depending on the type of cell junction. At the adherens...
Assembly of Signaling Complexes
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Amplifying Signals via Enzymatic Cascade
The JAK-STAT Signaling Pathway
Activation and Inactivation of G Proteins
GTPases and their Regulation
Large G-proteins, also known...

