Figure 1. Schematic cartoons of the Fz/PCP core components across a two-cell border.

Note that Fz and Vang act in both the interpretation of the long-range signal(s) – Wg and dWnt4 - as well as the short-range/local cell-cell transmembrane interactions. The latter is also mediated by homophilic interactions of Fmi and Fw. The cytoplasmic components Dsh, Dgo, and Pk are essential for the negative feedback loops within individual cells, as they antagonize each other. Dgo, Diego; Dsh, Dishevelled; Fmi, Flamingo; Fw, Furrowed; Fz, Frizzled; PCP, planar cell polarity; PK, Prickle; Vang, Van Gogh.