Ksenia Terekhova, Sabine Pokutta, Yee S. Kee, Jing Li, Emad Tajkhorshid, Gerald
Fuller, Alexander R. Dunn, and William I. Weis.
Binding partner- and force-promoted changes in αE-catenin
conformation probed by native cysteine labeling.
Scientific Reports, 9:15375, 2019.
(PMC: PMC6814714)
TERE2019-ET
Adherens Junctions (AJs) are cell-cell adhesion complexes that sense and propagate mechanical forces by coupling cadherins to the actin
cytoskeleton via -catenin and the F-actin binding protein E-catenin. When subjected to mechanical force, the
cadherincatenin complex can tightly link to F-actin through E-catenin, and also recruits the F-actin-binding protein
vinculin. In this study, labeling of native cysteines combined with mass spectrometry revealed conformational changes in E-catenin
upon binding to the E-cadherin-catenin complex, vinculin and F-actin. A method to apply physiologically meaningful forces in
solution revealed force-induced conformational changes in E-catenin when bound to F-actin. Comparisons of wild-type E-
catenin and a mutant with enhanced vinculin affinity using cysteine labeling and isothermal titration calorimetry provide evidence for
allosteric coupling of the N-terminal -catenin-binding and the middle (M) vinculin-binding domain of E-catenin. Cysteine
labeling also revealed possible crosstalk between the actin-binding domain and the rest of the protein. The data provide insight into how
binding partners and mechanical stress can regulate the conformation of full-length E-catenin, and identify the M domain as a key
transmitter of conformational changes.