Project description:To investigate the role of Hippo-YAP signaling in angiogenesis, we performed RNA-sequencing by using lung ECs isolated from mice with EC-specific deletion of indicated components of Hippo pathway.
Project description:To investigate the role of Hippo-YAP signaling in angiogenesis, we performed RNA-sequencing by using brain ECs isolated from mice with EC-specific deletion of indicated components of Hippo pathway.
Project description:Proper lung function relies on precisely balanced numbers of specialized epithelial cell types that work together and are maintained in homeostasis. In this study we have described essential roles for the transcriptional regulators YAP and TAZ, which are key effectors of Hippo pathway signaling, in maintaining lung epithelial homeostasis. Phenotypes associated with Yap/Taz deletion include alveolar defects and a striking development of goblet cell metaplasia throughout the airways. Lineage specific deletion of Yap and Taz in Scgb1a1+ cells leads to increased Mucin production within the knockout cells in vivo. In order better characterize the in vivo transcriptional changes associated with Yap/Taz knockout in these cells, we have isolated Scgb1a1 lineage traced cells from control and yap/taz cNull mice and performed bulk RNA sequencing.
Project description:Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive Schwann cell (SC)-lineage derived sarcomas with poor prognosis. The molecular events underlying SC lineage cells-to-MPNST transformation remain elusive. Here, we show that human MPNSTs exhibit elevated HIPPO-TAZ/YAP expression, and that TAZ/YAP hyperactivity in SCs caused by Lats1/2 loss potently induces high-grade nerve-associated tumors with full penetrance. Lats1/2 deficiency reprograms SCs to a cancerous, progenitor-like phenotype and promotes hyper-proliferation. Conversely, disruption of TAZ/YAP activity alleviates tumor burden in Lats1/2-deficient mice and inhibits human MPNST cell proliferation. Moreover, genome-wide target profiling reveals that TAZ/YAP-TEAD1 directly activates a set of oncogenic programs in SCs including PDGFR/RAF signaling. Co-targeting TAZ/YAP and PDGFR/RAF signaling efficaciously reduces tumorigenicity in Lats1/2-deficient tumors. Thus, our findings establish a previously unrecognized convergence between LATS1/2-TAZ/YAP pathway and MPNST pathogenesis, suggesting that combined inhibition of TAZ/YAP-PDGFR/RAF signaling may be beneficial in MPNSTs.
Project description:Angiogenesis, the process by which endothelial cells (ECs) form new blood vessels from existing ones, is intimately linked to the tissue's metabolic milieu and often occurs at nutrient-deficient sites. However, ECs rely on sufficient metabolic resources to support growth and proliferation. How endothelial nutrient acquisition and usage are regulated is unknown. Here we show that these processes are dictated by YAP/TAZ-TEAD – a transcriptional module whose function is highly responsive to changes in the tissue environment. ECs lacking YAP/TAZ or their transcriptional partners, TEAD1, 2, and 4 fail to divide, resulting in stunted vascular growth in mice. Conversely, activation of TAZ, the more abundant paralogue in ECs, boosts proliferation, leading to vascular hyperplasia. We find that YAP/TAZ promote angiogenesis by fueling nutrient mTORC1 signaling. By orchestrating the transcription of a repertoire of cell-surface transporters, YAP/TAZ-TEAD stimulate the import of amino acids and other essential nutrients, thereby enabling mTORC1 pathway activation. Dissociating mTORC1 from these nutrient inputs – elicited by the loss of Rag GTPases – inhibits mTORC1 activity and prevents YAP/TAZ-dependent vascular growth. These findings define a pivotal role for YAP/TAZ-TEAD in steering endothelial mTORC1 and illustrate the essentiality of coordinated nutrient fluxes in the vasculature.
Project description:Adipose tissues serve as an energy reservoir and endocrine organ, yet the mechanisms that coordinate these functions remain elusive. Here, we show that transcriptional coregulators YAP and TAZ mediate the crosstalk between fat mass and leptin levels to maintain metabolic homeostasis. Activating YAP/TAZ in adipocytes by Lats1 and Lats2 deletion results in a profound reduction in fat mass by converting mature adipocytes into delipidated progenitor-like cells. Surprisingly, Lats1/2 knockout mice did not exhibit lipodystrophy-related metabolic dysfunction, attributed to a paradoxical increase in circulating leptin levels. Mechanistically, YAP/TAZ-TEAD signaling upregulates leptin expression by directly binding an upstream enhancer site of the leptin gene. We further show that YAP/TAZ activity is linked to, and functionally required for, leptin regulation during fasting and refeeding. These results suggest that adipocyte Hippo-YAP/TAZ plays an essential role in coordinating adipose storage capacity and systemic energy balance through dual control of adipocyte plasticity and leptin gene transcription.
Project description:The two effector proteins of the Hippo signaling pathway, YAP and TAZ, play a pivotal role in the cellular homeostasis of podocytes and in the pathogenesis of focal segmental glomerulosclerosis (FSGS). We aim to unravel the unique and redundant functions of YAP and TAZ in the podocyte by identifying podocyte-specific interactors. We generated stable heat sensitive mouse podocytes (hsMPs) carrying a single copy integration of a transgenic construct expressing a flagged version of mouse Yap (3XFLAG.YAP), Taz (3XFLAG.TAZ) or Ruby (3XFLAG.RUBY) in the Rosa26 locus. To explore the interactome of YAP and TAZ in podocytes we immunoprecipitated the tagged proteins and characterized the co-immunoprecipitated protein complexes by mass spectrometry. Within the interactome analyses of the hsMPs, we identified shared and non-shared interacting proteins between YAP and TAZ. Among these identified proteins many well established interactors of YAP and TAZ were included, like proteins of the Tead family, different angiomotins or large tumor suppressor kinase 1 (Lats1). Strikingly, among the shared proteins were numerous proteins of the nuclear shuttling machinery, like importins (Ipo), exportins (Xpo), transportins (Tnpo) and nucleoporins (Nup) that form the nuclear pore complex (NPC), such as NUP107, NUP133, NUP205 and XPO5.
Project description:Proper lung function relies on precisely balanced numbers of specialized epithelial cell types that work together and are maintained in homeostasis. We describe essential roles for the transcriptional regulators Yap and Taz, which are key effectors of Hippo pathway signaling, in maintaining lung epithelial homeostasis. We report that conditional deletion of Yap1/Yap and Wwtr1/Taz in the lung epithelium of adult mice results in severe defects with consequent animal lethality. Phenotypes associated with Yap/Taz deletion include alveolar defects and a striking development of goblet cell metaplasia throughout the airways. We performed gene expression analysis of wild type and Yap/Taz null primary mouse airway epithelial cells in order to define Yap/Taz controlled gene expression.
Project description:Purpose: We aimed to elucidate the unique consequences of YAP/TAZ activation in pancreatic ductal cells. Methods: We isolated RNA from Lats1 and Lats2 double knockout ductal cells from Lats1fl/fl; Lats2fl/fl; Sox9-CreER mice. Results: Oncogenic activation of YAP in ductal cells lead to the rapid development of carcinoma in situ with microinvasion.