A DIX domain mutant (top) fails to self-aggregate (dots, bottom) or send signals.
BIENZ/MACMILLAN
The signal transduction protein in question, called Dishevelled (Dvl), is recruited to the plasma membrane when extracellular Wnt ligands bind to cell surface receptors. Dvl forms highly dynamic protein assemblies when overexpressed. Schwarz-Romond et al. now show that the ability to naturally aggregate correlates with Dvl's ability to transduce Wnt signals.
Signaling by Dvl was known to be dependent on a region of the protein called the DIX domain. The team now shows that mutations to this domain also impair homooligomerization.
Electron microscopy and ultracentrifugation revealed that wild-type homooligomers created long fibrils that formed and fell apart in a concentration-dependent manner. The...
