Figure 5.

Regulatory role of the Hippo signaling pathway in ciliogenesis. The cilium is indicated with two microtubule doublets (red robs) bounded with the ciliary membrane, the transition zone (grey trapezoidal cylinder), and the basal body (blue cylinder) formed with the mother centriole. In the Hippo signaling pathway, Activated LATS1/2 phosphorylate and inhibit the translocation of YAP/TAZ from the cytoplasm to the nucleus. LATS1/2 is activated by MST1/2 through direct phosphorylation, which is promoted by the scaffold protein, phosphorylated SAV1. The YAP/TAZ act as transcriptional coactivators and interact with the TEAD transcription factor 4 (TEAD 4) to regulate the expression of Aurka. The AURKA phosphorylates and activates the tubulin deacetylase HDAC6 to promote ciliary disassembly. In the absence of PC1, decreased MST1 and LATS1 may promote YAP/TAZ nuclear translocation, facilitate Aurka transcription and subsequent ciliary disassembly. The blue-arrow lines indicate positive regulation.