Public Summary of Scientific Progress:
The Hippo tumor suppressor pathway plays a major role in limiting tissue and organ growth. A major molecular function of the Hippo pathway is to inhibit the YAP oncoprotein, which promote tissue growth. Mutations in the Hippo pathway can result in tissue overgrowth and tumor formation. Inhibition of the Hippo pathway is also important for wound healing and tissue regeneration. We have investigated the mechanism of the Hippo pathway regulation and its role in stemness and differentiation. We found that the Hippo pathway is regulated by signals, such as cell contact. Our new data support a critical role of the Hippo pathway in maintenance of embryonic stem cell stemness and in vitro differentiation of stem cells. Therefore, activation of the Hippo pathway may promote differentiation while inhibition of this pathway may main stem cell population.