Project description:The Hippo pathway effectors yes-associated protein (YAP) and WW domain containing transcription regulator 1 (TAZ/WWTR1) support tumor initiation and progression in various cancer types. However, to which extent YAP and TAZ cooperatively contribute to cholangiocarcinoma (CCA) development and progression is poorly understood. Our immunohistochemical studies showed that YAP and TAZ were expressed in different CCA subtypes. However, nuclear co-expression was not frequently detected. RNAinterference (RNAi) experiments illustrated that YAP and TAZ supported CCA cell viability. Comprehensive expression profiling of HUCCT-1 cells after combined silencing of YAP/TAZ revealed a potential impact on chromosomal instability.
Project description:The optic vesicle comprises a pool of bi-potential progenitor cells from which the retinal pigment epithelium (RPE) and neural retina fates segregate during ocular morphogenesis. Several transcription factors and signaling pathways have been shown to be important for RPE maintenance and differentiation, but an understanding of the initial fate specification and determination of this ocular cell type is lacking. We show that Yap/Taz-Tead activity is necessary and sufficient for optic vesicle progenitors to adopt RPE identity in zebrafish. A Teadresponsive transgene is expressed within the domain of the optic cup from which RPE arises, and Yap immunoreactivity localizes to the nuclei of prospective RPE cells. yap (yap1) mutants lack a subset of RPE cells and/or exhibit coloboma. Loss of RPE in yap mutants is exacerbated in combination with taz (wwtr1) mutant alleles such that, when Yap and Taz are both absent, optic vesicle progenitor cells completely lose their ability to form RPE. The mechanism of Yap dependent RPE cell type determination is reliant on both nuclear localization of Yap and interaction with a Tead co-factor. In contrast to loss of Yap and Taz, overexpression of either protein within optic vesicle progenitors leads to ectopic pigmentation in a dosagedependent manner. Overall, this study identifies Yap and Taz as key early regulators of RPE genesis and provides a mechanistic framework for understanding the congenital ocular defects of Sveinsson’s chorioretinal atrophy and congenital retinal coloboma. 60 pooled eyes from 36 hpf wild type or vsx2:Gal4/dsRed:14xUAS:YapS87A embryos were pooled for one sample. Three wild type and three vsx2:Gal4/dsRed:14xUAS:YapS87A pools were analyzed for RNA.
Project description:The YAP pathway in regulating organ size by integrating external signals to control the expression of genes involved in cell proliferation. YAP is known to be involved in tumorigenesis in several tissues, yet its role in cholangiocarcinoma is not established We used microarrays to assess the role of YAP pathway in cholangiocarcinoma either by overexpressing a constitutively active YAP1 mutant, or by downregulating YAP1 expression using shRNA HuCCT1 cells where transfected with either an empty vector or a vector overexpressing the constitutively active YAP1 S127A; cells were harvested, RNA was collected and analyzed using microarray
Project description:The YAP pathway in regulating organ size by integrating external signals to control the expression of genes involved in cell proliferation. YAP is known to be involved in tumorigenesis in several tissues, yet its role in cholangiocarcinoma is not established We used microarrays to assess the role of YAP pathway in cholangiocarcinoma either by overexpressing a constitutively active YAP1 mutant, or by downregulating YAP1 expression using shRNA HuCCT1 cells where transfected with either a control scrambled shRNA or a shRNA targeting YAP1; cells were harvested, RNA was collected and analyzed using microarray
Project description:The YAP pathway in regulating organ size by integrating external signals to control the expression of genes involved in cell proliferation. YAP is known to be involved in tumorigenesis in several tissues, yet its role in cholangiocarcinoma is not established We used microarrays to assess the role of YAP pathway in cholangiocarcinoma either by overexpressing a constitutively active YAP1 mutant, or by downregulating YAP1 expression using shRNA HuCCT1 cells where transfected with either an empty vector or a vector overexpressing the constitutively active YAP1 S127A; cells were harvested, RNA was collected and analyzed using microarray
Project description:The Hippo pathway downstream effectors, Yap and Taz, play key roles in cell proliferation and tissue growth, regulating gene expression especially via interaction with Tead transcription factors. To investigate their role in skeletal muscle stem cells, we analysed gene expression changes driven by Taz and compared these to Yap mediated changes to the transcriptome by measurement of gene expression on Affymetrix microarrays. To interrogate overlapping and unique transcriptional changes driven by these Hippo effectors, satellite cell-derived myoblasts were transduced with constitutively active TAZ S89A or YAP S127A retrovirus for 24h or 48h, with empty retrovirus as control. Triplicate microarray analyses of empty vector controls, hYAP1 S127A and TAZ S89A transgenic primary myoblasts were conducted.