Figure 7.

Model summarizing the findings presented in this work. WOX5 acts within the QC, maybe together with an unknown factor(s), to maintain its organization. WOX5 presence within the QC is sufficient to regulate CSC maintenance, probably in combination with other factors, whose activity or expression might depend on WOX5 and could act as a non-cell-autonomous signal. WOX5 can move through PDs into adjacent cells, where its exact function is not clear. The CLE40p/CLV1/ACR4 signaling pathway overall antagonizes the activity of the QC, promoting CSC differentiation. Increased signaling of CLE40 leads to an up-regulation of WOX5 expression in a new vascular domain, which is dependent on the CLV2 receptor. This allows establishment of a new QC at the sites of the vascular initials upon loss of QC identity after prolonged CLE40 signaling. V, vascular region.