Transcriptional regulator which can act both as a coactivator and a corepressor and is the critical downstream regulatory target in the Hippo signaling pathway that plays a pivotal role in organ size control and tumor suppression by restricting proliferation and promoting apoptosis (By similarity). Required for expansion of the neural plate and neural plate border zone progenitor pools. Acts as a direct regulator of pax3 expression via interaction with tead1 (PubMed:21687713). Plays a key role in tissue tension and 3D tissue shape by regulating cortical actomyosin network formation (PubMed:25778702). Both phosphorylation and cell density can regulate its subcellular localization. Phosphorylation sequesters it in the cytoplasm by inhibiting its translocation into the nucleus. At low density, predominantly nuclear and is translocated to the cytoplasm at high density. Expressed in the notochord, brain, eyes, branchial arches and pectoral fins. Maternally expressed in the embryo: maternal expression is ubiquitous. Phosphorylated by lats1 and lats2; leading to cytoplasmic translocation and inactivation. Embryos display a small head with smaller eyes than normal and fewer cartilages in the branchial arches. Marked increase in cell death in brain (PubMed:19393221). Incomplete epiboly at gastrulation, characterized by blastopore closure defects and impaired axis formation (PubMed:21687713). Belongs to the YAP1 family. Shaping life - Issue 175 of January 2016