Ror2/Frizzled complex mediates Wnt5a-induced AP-1 activation by regulating Dishevelled polymerization

M Nishita, S Itsukushima, A Nomachi… - … and cellular biology, 2010 - Am Soc Microbiol
M Nishita, S Itsukushima, A Nomachi, M Endo, ZC Wang, D Inaba, S Qiao, S Takada
Molecular and cellular biology, 2010Am Soc Microbiol
The receptor tyrosine kinase Ror2 acts as a receptor or coreceptor for Wnt5a to mediate
Wnt5a-induced activation of the Wnt/JNK pathway and inhibition of the β-catenin-dependent
canonical Wnt pathway. However, little is known about how Ror2 cooperates with another
receptor component (s) to mediate Wnt5a signaling. We show here that Ror2 regulates
Wnt5a-induced polymerization of Dishevelled (Dvl) and that this Ror2-mediated regulation
of Dvl is independent of the cytoplasmic region of Ror2. Ror2 can associate with Frizzled7 …
Abstract
The receptor tyrosine kinase Ror2 acts as a receptor or coreceptor for Wnt5a to mediate Wnt5a-induced activation of the Wnt/JNK pathway and inhibition of the β-catenin-dependent canonical Wnt pathway. However, little is known about how Ror2 cooperates with another receptor component (s) to mediate Wnt5a signaling. We show here that Ror2 regulates Wnt5a-induced polymerization of Dishevelled (Dvl) and that this Ror2-mediated regulation of Dvl is independent of the cytoplasmic region of Ror2. Ror2 can associate with Frizzled7 (Fz7) via its extracellular cysteine-rich domain to form a receptor complex that is required for the regulation of Dvl and activation of the AP-1 promoter after Wnt5a stimulation. Suppressed expression of Fz7 indeed results in the inhibition of Wnt5a-induced polymerization of Dvl and AP-1 activation. Interestingly, both the DIX and the DEP domains of Dvl are indispensable for Dvl polymerization and subsequent AP-1 activation after Wnt5a stimulation. We further show that polymerized Dvl is colocalized with Rac1 and that suppressed expression of Rac1 inhibits Wnt5a-induced AP-1 activation. Collectively, our results indicate that Ror2/Fz receptor complex plays an important role in the Wnt5a/Rac1/AP-1 pathway by regulating the polymerization of Dvl.
American Society for Microbiology