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 (PubMed:17974916, PubMed:18280240, PubMed:18579750, PubMed:21364637, PubMed:30447097). The core of this pathway is composed of a kinase cascade wherein STK3/MST2 and STK4/MST1, in complex with its regulatory protein SAV1, phosphorylates and activates LATS1/2 in complex with its regulatory protein MOB1, which in turn phosphorylates and inactivates YAP1 oncoprotein and WWTR1/TAZ (PubMed:18158288). Plays a key role in tissue tension and 3D tissue shape by regulating cortical actomyosin network formation. Acts via ARHGAP18, a Rho GTPase activating protein that suppresses F-actin polymerization (PubMed:25778702). Plays a key role in controlling cell proliferation in response to cell contact. Phosphorylation of YAP1 by LATS1/2 inhibits its translocation into the nucleus to regulate cellular genes important for cell proliferation, cell death, and cell migration (PubMed:18158288). The presence of TEAD transcription factors are required for it to stimulate gene expression, cell growth, anchorage-independent growth, and epithelial mesenchymal transition (EMT) induction (PubMed:18579750). Suppresses ciliogenesis via acting as a transcriptional corepressor of the TEAD4 target genes AURKA and PLK1 (PubMed:25849865). In conjunction with WWTR1, involved in the regulation of TGFB1-dependent SMAD2 and SMAD3 nuclear accumulation (By similarity). Activates the C-terminal fragment (CTF) of ERBB4 (isoform 3). Activates the C-terminal fragment (CTF) of ERBB4 (isoform 3). Binds to the SH3 domain of the YES kinase. Binds to WBP1 and WBP2 (PubMed:9202023). Binds, in vitro, through the WW1 domain, to neural isoforms of ENAH that contain the PPSY motif (By similarity). The phosphorylated form interacts with YWHAB (PubMed:17974916). Interacts (via WW domains) with LATS1 (via PPxY motif 2) (PubMed:18158288). Interacts with LATS2 (PubMed:18158288). Interacts with TEAD1, TEAD2, TEAD3 and TEAD4 (PubMed:18579750, PubMed:20123905, PubMed:20123908). Interacts with TP73 (PubMed:18280240). Interacts with RUNX1 (PubMed:18280240). Interacts with HCK (PubMed:17535448). Interacts (via WW domains) with PTPN14 (via PPxY motif 2); this interaction leads to the cytoplasmic sequestration of YAP1 and inhibits its transcriptional coactivator activity (PubMed:22525271). Interacts (when phosphorylated at Ser-127) with SMAD2, SMAD3 and WWTR1 (By similarity). Interacts with PRRG2 (via cytoplasmic domain) (PubMed:17502622). Interacts (via WW domains) with PRRG4 (via cytoplasmic domain) (PubMed:23873930). Interacts (via WW domain 1) with isoform 3 of ERBB4 (via PPxY motif 2). Interacts (via WW domain 1) with isoform 3 of ERBB4 (via PPxY motif 2). Both phosphorylation and cell density can regulate its subcellular localization (PubMed:18158288, PubMed:20048001). Phosphorylation sequesters it in the cytoplasm by inhibiting its translocation into the nucleus (PubMed:18158288, PubMed:20048001). At low density, predominantly nuclear and is translocated to the cytoplasm at high density (PubMed:18158288, PubMed:20048001, PubMed:25849865). PTPN14 induces translocation from the nucleus to the cytoplasm (PubMed:22525271). Localized mainly to the nucleus in the early stages of embryo development with expression becoming evident in the cytoplasm at the blastocyst and epiblast stages (By similarity). Isoforms of the YAP1-1 form contain only one WW domain. Increased expression seen in some liver and prostate cancers. Isoforms lacking the transactivation domain found in striatal neurons of patients with Huntington disease (at protein level). The first coiled-coil region mediates most of the interaction with TEAD transcription factors. Phosphorylated by LATS1 and LATS2; leading to cytoplasmic translocation and inactivation (PubMed:18158288, PubMed:20048001). Phosphorylated by ABL1; leading to YAP1 stabilization, enhanced interaction with TP73 and recruitment onto proapoptotic genes; in response to DNA damage (PubMed:18280240). Phosphorylation at Ser-400 and Ser-403 by CK1 is triggered by previous phosphorylation at Ser-397 by LATS proteins and leads to YAP1 ubiquitination by SCF(beta-TRCP) E3 ubiquitin ligase and subsequent degradation (PubMed:20048001). Phosphorylated at Thr-119, Ser-138, Thr-154, Ser-367 and Thr-412 by MAPK8/JNK1 and MAPK9/JNK2, which is required for the regulation of apoptosis by YAP1 (PubMed:21364637). Ubiquitinated by SCF(beta-TRCP) E3 ubiquitin ligase. The disease is caused by variants affecting the gene represented in this entry. Highest expression in ovary and placenta, lowest in skeletal muscle and brain. Belongs to the YAP1 family. Shaping life - Issue 175 of January 2016