Angiomotin-like Proteins Associate with and Negatively Regulate YAP1

Abstract

In both Drosophila and mammalian systems, the Hippo pathway plays an important role in controlling organ size, mainly through its ability to regulate cell proliferation and apoptosis. The key component in the Hippo pathway is the Yes-associated protein YAP1, which localizes in nucleus, functions as a transcriptional coactivator, and regulates the expression of several proliferation-and apoptosis-related genes. The Hippo pathway negatively regulates YAP1 transcriptional activity by modulating its nuclear-cytoplasmic localization in a phosphorylation-dependent manner. Here, we describe the identification of several new PY motif-containing proteins, including angiomotin-like protein 1 (AMOTL1) and 2 (AMOTL2), as YAP1-associated proteins. We demonstrate that AMOTL1 and AMOTL2 can regulate YAP1 cytoplasm-tonucleus translocation through direct protein-protein interaction, which can occur independent of YAP1 phosphorylation status. Moreover, down-regulation of AMOTL2 in MCF10A cells promotes epithelial-mesenchymal transition, a phenotype that is also observed in MCF10A cells with YAP1 overexpression. Together, these data support a new mechanism for YAP1 regulation, which is mediated via its direct interactions with angiomotin-like proteins.

AmotL2 disrupts apical–basal cell polarity and promotes tumour invasion

“…Amot, AmotL1 and AmotL2 all contain WW-binding motifs that interact with the Yap1 oncoprotein, which is then retained in the cellular junctions [47][48][49] . This suggests a tumour-suppressive role of p100 AmotL2.…”

The Hippo pathway regulates stem cell proliferation, self-renewal, and differentiation

“…YAP could interact with angiomotin (AMOT) family proteins (Varelas et al, 2010;Wang et al, 2010;Chan et al, 2011;Zhao et al, 2011), which results in YAP localization to tight junction and YAP inhibition through phosphorylation-dependent and -independent mechanisms (Zhao et al, 2011). YAP and TAZ also interact with another tight junction protein ZO-2, which was reported to increase nuclear localization of YAP and tightjunction localization of TAZ, respectively Remue et al, 2010).…”

Phosphorylation of the Hippo Pathway Component AMOTL2 by the mTORC2 Kinase Promotes YAP Signaling, Resulting in Enhanced Glioblastoma Growth and Invasiveness

“…Immunoprecipitations were performed as described previously (20), except RICTOR immunoprecipitations were performed using 0.3% CHAPS containing lysis buffer as described (11). For TORC2 in vitro kinase assay (11), RICTOR immunoprecipitates captured with protein G-Sepharose were washed four times with 0.3% CHAPS lysis buffer and once in kinase buffer (25 AMOTL2 and 500 M ATP. The reactions were stopped by the addition of 200 l of ice-cold dilution buffer (20 mM MOPS (pH 7.0), 1 mM EDTA, 0.01% Brij 35, 5% glycerol, 0.1% 2-mercaptoethanol, 1 mg/ml BSA).…”

“…-phosphorylated AMOTL2 Is Incapable of Binding YAP and Leads to Enhanced Expression of YAP Target Genes-AMOTL2 interacts strongly with YAP and suppresses YAPmediated transactivation (14,24,25). To determine whether the phosphorylation event on serine 760 had a functional role in the ability of AMOTL2 to bind to YAP and effect target gene expression, we cotransfected YAP with native human AMOTL2, a nonphosphorylatable (S760A) AMOTL2, or a phosphomimetic (S760E) AMOTL2 and assessed their ability to bind YAP via coimmunoprecipitation as shown in Fig.…”