Activation of Wnt/β-catenin signaling by Zeb1 in endothelial progenitors induces vascular quiescence entry.

The establishment of a functional vasculature requires endothelial cells to enter quiescence during the completion of development, otherwise pathological overgrowth occurs. How such a transition is regulated remains unclear. Here, we uncover a role of Zeb1 in defining vascular quiescence entry. During quiescence acquisition, Zeb1 increases along with the progressive decline of endothelial progenitors' activities, with Zeb1 loss resulting in endothelial overgrowth and vascular deformities. RNA sequencing (RNA-seq) and assay for transposase-accessible chromatin sequencing (ATAC-seq) analyses reveal that Zeb1 represses Wif1, thereby activating Wnt/β-catenin signaling. Knockdown of Wif1 rescues the overgrowth induced by Zeb1 deletion. Importantly, local administration of surrogate Wnt molecules in the retina ameliorates the overgrowth defects of Zeb1 mutants. These findings show a mechanism by which Zeb1 induces quiescence of endothelial progenitors during the establishing of vascular homeostasis, providing molecular insight into the inherited neovascular pathologies associated with human ZEB1 mutations, suggesting pharmacological activation of Wnt/β-catenin signaling as a potential therapeutical approach.