Since the surface of the ARM domain can typically accommodate only one peptide motif at any given time, all these proteins compete for the same cellular pool of β-catenin molecules. This competition is the key to understand how the Wnt signaling pathway works.
Because the ARM domain's surface can typically hold only one peptide motif simultaneously, all these proteins vie for control over the shared cellular pool of β-catenin molecules. Understanding this competition is crucial to grasping how the Wnt signaling pathway operates.