Data from: Wnt/PCP controls spreading of Wnt/β-catenin signals by cytonemes in vertebrates

Signaling filopodia, termed cytonemes, are dynamic actin-based membrane
structures that regulate the exchange of signaling molecules and their
receptors within tissues. However, how cytoneme formation is regulated
remains unclear. Here, we show that Wnt/PCP autocrine signaling controls
the emergence of cytonemes, and that cytonemes subsequently control
paracrine Wnt/β-catenin signal activation. Upon binding of the Wnt family
member Wnt8a, the receptor tyrosine kinase Ror2 gets activated. Ror2/PCP
signaling leads to induction of cytonemes, which mediate transport of
Wnt8a to neighboring cells. In the Wnt receiving cells, Wnt8a on cytonemes
triggers Wnt/β-catenin-dependent gene transcription and proliferation. We
show that cytoneme-based Wnt transport operates in diverse processes,
including zebrafish development, the murine intestinal crypt, and human
cancer organoids, demonstrating that Wnt transport by cytonemes and its
control via the Ror2 pathway is highly conserved in vertebrates.