Association of dishevelled with the clathrin AP-2 adaptor is required for frizzled endocytosis and planar cell polarity signaling
DEVELOPMENTAL CELL
Authors: Yu, Anan; Rual, Jean-Francois; Tamai, Keiko; Harada, Yuko; Vidal, Marc; He, Xi; Kirchhausen, Tomas
Abstract
Upon activation by Wnt, the Frizzled receptor is internalized in a process that requires the recruitment of Dishevelled. We describe a novel interaction between Dishevelled2 (Dvl2) and mu 2-adaptin, a subunit of the clathrin adaptor AP-2; this interaction is required to engage activated Frizzled4 with the endocytic machinery and for its internalization. The interaction of Dvl2 with AP-2 requires simultaneous association of the DEP domain and a peptide YHEL motif within Dvl2 with the C terminus of mu 2. Dvl2 mutants in the YHEL motif fail to associate with mu 2 and AP-2, and prevent Frizzled4 internalization. Corresponding Xenopus Dishevelled mutants show compromised ability to interfere with gastrulation mediated by the planar cell polarity (PCP) pathway. Conversely, a Dvl2 mutant in its DEP domain impaired in PCP signaling exhibits defective AP-2 interaction and prevents the internalization of Frizzled4. We suggest that the direct interaction of Dvl2 with AP-2 is important for Frizzled internalization and Frizzled/PCP signaling.
Identification of a novel Wnt5a-CK1 epsilon-Dvl2-Plk1-mediated primary cilia disassembly pathway
EMBO JOURNAL
Authors: Lee, Kyung Ho; Johmura, Yoshikazu; Yu, Li-Rong; Park, Jung-Eun; Gao, Yuan; Bang, Jeong K.; Zhou, Ming; Veenstra, Timothy D.; Kim, Bo Yeon; Lee, Kyung S.
Abstract
Non-motile primary cilium is an antenna-like structure whose defect is associated with a wide range of pathologies, including developmental disorders and cancer. Although mechanisms regulating cilia assembly have been extensively studied, how cilia disassembly is regulated remains poorly understood. Here, we report unexpected roles of Dishevelled 2 (Dvl2) and interphase polo-like kinase 1 (Plk1) in primary cilia disassembly. We demonstrated that Dvl2 is phosphorylated at S143 and T224 in a manner that requires both non-canonical Wnt5a ligand and casein kinase 1 epsilon (CK1 epsilon), and that this event is critical to interact with Plk1 in early stages of the cell cycle. The resulting Dvl2-Plk1 complex mediated Wnt5a-CK1 epsilon-Dvl2-dependent primary cilia disassembly by stabilizing the HEF1 scaffold and activating its associated Aurora-A (AurA), a kinase crucially required for primary cilia disassembly. Thus, via the formation of the Dvl2-Plk1 complex, Plk1 plays an unanticipated role in primary cilia disassembly by linking Wnt5a-induced biochemical steps to HEF1/AurA-dependent cilia disassembly. This study may provide new insights into the mechanism underlying ciliary disassembly processes and various cilia-related disorders. The EMBO Journal (2012) 31, 3104-3117. doi: 10.1038/emboj.2012.144; Published online 18 May 2012