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bioRxiv · 10.1101/2024.10.17.618965

A ZO-2 scaffolding mechanism regulates the Hippo signalling pathway.

Liu, O.·Lin, L.·Bunk, S.·Chew, T.·Wu, S.·Motegi, F.·Low, B. C.
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Abstract

Inhibition of proliferation upon contact is a critical cell density control mechanism governed by the Hippo signalling pathway. The biochemical signalling underlying cell density-dependent cues regulating Hippo signalling and its downstream effectors, YAP, remains poorly understood. Here, we reveal that the tight junction protein ZO-2 is required for the contact-mediated inhibition of proliferation. We additionally determined that the well-established molecular players of contact inhibition of proliferation, namely Hippo kinase LATS1 and YAP, are regulated by ZO-2, and that the scaffolding function of ZO-2 promotes the interaction with and phosphorylation of YAP by LATS1. Mechanistically, YAP is phosphorylated when ZO-2 brings LATS1 and YAP together via its SH3 and PDZ domains, respectively, subsequently leading to the cytoplasmic retention and inactivation of YAP. In conclusion, we demonstrate that ZO-2 maintains Hippo signalling pathway activation by promoting the stability of LATS1 to inactivate YAP.

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Liu, O., Lin, L., Bunk, S., Chew, T., Wu, S., Motegi, F., Low, B. C.. 2024-10-17. A ZO-2 scaffolding mechanism regulates the Hippo signalling pathway.. https://doi.org/10.1101/2024.10.17.618965

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