Yes-associated protein 1

YAP1 (Yes-associated protein 1) is a  transcriptional co-activator which acts as a major effector of Hippo signaling pathway that regulates organ size/ tissue homeostasis and cell proliferation, and is an established oncogene (1).  Hippo signaling activation results in the phosphorylation mediated inactivation of YAP1, and restriction of YAP1’s transcriptional activity is the principal mechanism of growth and tumor suppression by Hippo pathway.