Live imaging and conditional disruption of native PCP activity using endogenously tagged zebrafish sfGFP-Vangl2.

Tissue-wide coordination of polarized cytoskeletal organization and cell behaviour, critical for normal development, is controlled by asymmetric membrane localization of non-canonical Wnt/planar cell polarity (PCP) signalling components. Understanding the dynamic regulation of PCP thus requires visualization of these polarity proteins in vivo. Here we utilize CRISPR/Cas9 genome editing to introduce a fluorescent reporter onto the core PCP component, Vangl2, in zebrafish. Through live imaging of endogenous sfGFP-Vangl2 expression, we report on the authentic regulation of vertebrate PCP during embryogenesis. Furthermore, we couple sfGFP-Vangl2 with conditional zGrad GFP-nanobody degradation methodologies to interrogate tissue-specific functions for PCP. Remarkably, loss of Vangl2 in foxj1a-positive cell lineages causes ependymal cell cilia and Reissner fiber formation defects as well as idiopathic-like scoliosis. Together, our studies provide crucial insights into the establishment and maintenance of vertebrate PCP and create a powerful experimental paradigm for investigating post-embryonic and tissue-specific functions for Vangl2 in development and disease.