Faculty Opinions recommendation of TGF-β Targets the Hippo Pathway Scaffold RASSF1A to Facilitate YAP/SMAD2 Nuclear Translocation.

The conserved Hippo signaling pathway regulates organ size in Drosophila melanogaster and mammals and has an essential role in tumor suppression and the control of cell proliferation. Recent studies identified activators of Hippo signaling, but antagonists of the pathway have remained largely elusive. In this paper, we show that NPHP4, a known cilia-associated protein that is mutated in the severe degenerative renal disease nephronophthisis, acts as a potent negative regulator of mammalian Hippo signaling. NPHP4 directly interacted with the kinase Lats1 and inhibited Lats1-mediated phosphorylation of the Yes-associated protein (YAP) and TAZ (transcriptional coactivator with PDZ-binding domain), leading to derepression of these protooncogenic transcriptional regulators. Moreover, NPHP4 induced release from 14-3-3 binding and nuclear translocation of YAP and TAZ, promoting TEA domain (TEAD)/TAZ/YAP-dependent transcriptional activity. Consistent with these data, knockdown of NPHP4 negatively affected cellular proliferation and TEAD/TAZ activity, essentially phenocopying loss of TAZ function. These data identify NPHP4 as a negative regulator of the Hippo pathway and suggest that NPHP4 regulates cell proliferation through its effects on Hippo signaling.

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Dynamic patterns of YAP1 expression and cellular localization in the developing and injured utricle

10.1101/2020.05.06.081323 ◽

2020 ◽

Cited By ~ 1

Author(s):

Vikrant Borse ◽

Matthew Barton ◽

Harry Arndt ◽

Tejbeer Kaur ◽

Mark E. Warchol

Keyword(s):

Hair Cell ◽

Cellular Localization ◽

Cell Injury ◽

Nuclear Translocation ◽

Cell Damage ◽

Hippo Pathway ◽

Hippo Signaling ◽

Supporting Cells ◽

The Hippo Pathway

AbstractThe Hippo pathway is an evolutionarily conserved signaling pathway involved in regulating organ size, development, homeostasis and regeneration1–4. YAP1 is a transcriptional coactivator and the primary effector of Hippo signaling. Upstream activation of the Hippo pathway leads to nuclear translocation of YAP1, which then evokes changes in gene expression and cell cycle entry5. A prior study has demonstrated nuclear translocation of YAP1 in the supporting cells of the developing utricle6, but the possible role of YAP1 in hair cell regeneration is unclear. The present study characterizes the cellular localization of YAP1 in the utricles of mice and chicks, both under normal conditions and after hair cell injury. During neonatal development of the mouse utricle, YAP1 expression was observed in the cytoplasm of supporting cells, and was also transiently expressed in the cytoplasm of hair cells. We also observed temporary nuclear translocation of YAP1 in supporting cells of the mouse utricle at short time periods after placement in organotypic culture. However, little or no nuclear translocation of YAP1 was observed after injury to the utricles of neonatal or mature mice. In contrast, a significant degree of YAP1 nuclear translocation was observed in the chicken utricle after streptomycin-induced hair cell damage in vitro and in vivo. Together, these data suggest that differences in YAP1 signaling may be partly responsible for the distinct regenerative abilities of the avian vs. mammalian inner ear.

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S-nitrosylation-mediated coupling of G-protein alpha-2 with CXCR5 induces Hippo/YAP-dependent diabetes-accelerated atherosclerosis

Nature Communications ◽

10.1038/s41467-021-24736-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Meng-Lin Chao ◽

Shanshan Luo ◽

Chao Zhang ◽

Xuechun Zhou ◽

Miao Zhou ◽

...

Keyword(s):

Nuclear Translocation ◽

Hippo Pathway ◽

Diabetic Patients ◽

Guanine Nucleotide Binding Protein ◽

Accelerated Atherosclerosis ◽

Endothelial Inflammation ◽

Patients With Diabetes ◽

Guanine Nucleotide Binding ◽

The Hippo Pathway ◽

The Impact

AbstractAtherosclerosis-associated cardiovascular disease is one of the main causes of death and disability among patients with diabetes mellitus. However, little is known about the impact of S-nitrosylation in diabetes-accelerated atherosclerosis. Here, we show increased levels of S-nitrosylation of guanine nucleotide-binding protein G(i) subunit alpha-2 (SNO-GNAI2) at Cysteine 66 in coronary artery samples from diabetic patients with atherosclerosis, consistently with results from mice. Mechanistically, SNO-GNAI2 acted by coupling with CXCR5 to dephosphorylate the Hippo pathway kinase LATS1, thereby leading to nuclear translocation of YAP and promoting an inflammatory response in endothelial cells. Furthermore, Cys-mutant GNAI2 refractory to S-nitrosylation abrogated GNAI2-CXCR5 coupling, alleviated atherosclerosis in diabetic mice, restored Hippo activity, and reduced endothelial inflammation. In addition, we showed that melatonin treatment restored endothelial function and protected against diabetes-accelerated atherosclerosis by preventing GNAI2 S-nitrosylation. In conclusion, SNO-GNAI2 drives diabetes-accelerated atherosclerosis by coupling with CXCR5 and activating YAP-dependent endothelial inflammation, and reducing SNO-GNAI2 is an efficient strategy for alleviating diabetes-accelerated atherosclerosis.

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Targeting IRF3 as a YAP agonist therapy against gastric cancer

Journal of Experimental Medicine ◽

10.1084/jem.20171116 ◽

2018 ◽

Vol 215 (2) ◽

pp. 699-718 ◽

Cited By ~ 16

Author(s):

Shi Jiao ◽

Jingmin Guan ◽

Min Chen ◽

Wenjia Wang ◽

Chuanchuan Li ◽

...

Keyword(s):

Gastric Cancer ◽

Target Genes ◽

Nuclear Translocation ◽

Patient Survival ◽

Hippo Pathway ◽

Vital Role ◽

Dependent Manner ◽

Genome Wide ◽

The Hippo Pathway ◽

Innate Antiviral Immunity

The Hippo pathway plays a vital role in tissue homeostasis and tumorigenesis. The transcription factor IRF3 is essential for innate antiviral immunity. In this study, we discovered IRF3 as an agonist of Yes-associated protein (YAP). The expression of IRF3 is positively correlated with that of YAP and its target genes in gastric cancer; the expression of both IRF3 and YAP is up-regulated and prognosticates patient survival. IRF3 interacts with both YAP and TEAD4 in the nucleus to enhance their interaction, promoting nuclear translocation and activation of YAP. IRF3 and YAP–TEAD4 are associated genome-wide to cobind and coregulate many target genes of the Hippo pathway. Overexpression of active IRF3 increased, but depletion of IRF3 reduced, the occupancy of YAP on the target genes. Knockdown or pharmacological targeting of IRF3 by Amlexanox, a drug used clinically for antiinflammatory treatment, inhibits gastric tumor growth in a YAP-dependent manner. Collectively, our study identifies IRF3 as a positive regulator for YAP, highlighting a new therapeutic target against YAP-driven cancers.

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Metabolic Alterations in Spheroid-Cultured Hepatic Stellate Cells

International Journal of Molecular Sciences ◽

10.3390/ijms21103451 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3451 ◽

Cited By ~ 1

Author(s):

Koichi Fujisawa ◽

Taro Takami ◽

Nanami Sasai ◽

Toshihiko Matsumoto ◽

Naoki Yamamoto ◽

...

Keyword(s):

Gene Expression ◽

Hepatic Stellate Cells ◽

Nuclear Translocation ◽

Smooth Muscle Actin ◽

Hippo Pathway ◽

Lipid Synthesis ◽

Stellate Cells ◽

Vital Role ◽

Metabolome Analysis ◽

The Hippo Pathway

Hepatic stellate cells (HSCs) play a vital role in liver fibrosis, and a greater understanding of their regulation is required. Recent studies have focused on relationships between extracellular matrix (ECM) stiffness and gene expression or cellular metabolism, but none have provided a detailed metabolic analysis of HSC changes in spheroid cultures. Accordingly, in the present study, we created an HSC spheroid culture and analyzed changes in gene expression and metabolism. Expression of α-smooth muscle actin (α-SMA) decreased in the spheroids, suppressing proliferation. Gene expression analysis revealed the cell cycle, sirtuin signaling, mitochondrial dysfunction, and the Hippo pathway to be canonical pathways, believed to result from decreased proliferative ability or mitochondrial suppression. In the Hippo pathway, nuclear translocation of the yes-associated protein (YAP) was decreased in the spheroid, which was associated with the stiffness of the ECM. Metabolome analysis showed glucose metabolism changes in the spheroid, including glutathione pathway upregulation and increased lipid synthesis. Addition of the glycolytic product phosphoenolpyruvate (PEP) led to increased spheroid size, with increased expression of proteins such as α-SMA and S6 ribosomal protein (RPS6) phosphorylation, which was attributed to decreased suppression of translation. The results of our study contribute to the understanding of metabolic changes in HSCs and the progression of hepatic fibrosis.

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Dynamic patterns of YAP1 expression and cellular localization in the developing and injured utricle

Scientific Reports ◽

10.1038/s41598-020-77775-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vikrant Borse ◽

Matthew Barton ◽

Harry Arndt ◽

Tejbeer Kaur ◽

Mark E. Warchol

Keyword(s):

Inner Ear ◽

Cellular Localization ◽

Nuclear Translocation ◽

Hippo Pathway ◽

Hippo Signaling ◽

Supporting Cells ◽

The Hippo Pathway

AbstractThe Hippo signaling pathway is a key regulator of tissue development and regeneration. Activation of the Hippo pathway leads to nuclear translocation of the YAP1 transcriptional coactivator, resulting in changes in gene expression and cell cycle entry. Recent studies have demonstrated the nuclear translocation of YAP1 during the development of the sensory organs of the inner ear, but the possible role of YAP1 in sensory regeneration of the inner ear is unclear. The present study characterized the cellular localization of YAP1 in the utricles of mice and chicks, both under normal conditions and after HC injury. During neonatal development, YAP1 expression was observed in the cytoplasm of supporting cells, and was transiently expressed in the cytoplasm of some differentiating hair cells. We also observed temporary nuclear translocation of YAP1 in supporting cells of the mouse utricle after short periods in organotypic culture. However, little or no nuclear translocation of YAP1 was observed in the utricles of neonatal or mature mice after ototoxic injury. In contrast, substantial YAP1 nuclear translocation was observed in the chicken utricle after streptomycin treatment in vitro and in vivo. Together, these data suggest that differences in YAP1 signaling may partially account for the differing regenerative abilities of the avian vs. mammalian inner ear.

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MAML1/2 promote YAP/TAZ nuclear localization and tumorigenesis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1917969117 ◽

2020 ◽

Vol 117 (24) ◽

pp. 13529-13540 ◽

Cited By ~ 1

Author(s):

Jiyoung Kim ◽

Hyeryun Kwon ◽

You Keun Shin ◽

Gahyeon Song ◽

Taebok Lee ◽

...

Keyword(s):

Nuclear Localization ◽

Messenger Rna ◽

Molecular Mechanisms ◽

Nuclear Translocation ◽

Human Cancer ◽

Hippo Pathway ◽

Ectopic Expression ◽

Dependent Manner ◽

The Hippo Pathway

The Hippo pathway plays a pivotal role in tissue homeostasis and tumor suppression. YAP and TAZ are downstream effectors of the Hippo pathway, and their activities are tightly suppressed by phosphorylation-dependent cytoplasmic retention. However, the molecular mechanisms governing YAP/TAZ nuclear localization have not been fully elucidated. Here, we report that Mastermind-like 1 and 2 (MAML1/2) are indispensable for YAP/TAZ nuclear localization and transcriptional activities. Ectopic expression or depletion of MAML1/2 induces nuclear translocation or cytoplasmic retention of YAP/TAZ, respectively. Additionally, mutation of the MAML nuclear localization signal, as well as its YAP/TAZ interacting region, both abolish nuclear localization and transcriptional activity of YAP/TAZ. Importantly, we demonstrate that the level ofMAML1messenger RNA (mRNA) is regulated by microRNA-30c (miR-30c) in a cell-density-dependent manner. In vivo and clinical results suggest that MAML potentiates YAP/TAZ oncogenic function and positively correlates with YAP/TAZ activation in human cancer patients, suggesting pathological relevance in the context of cancer development. Overall, our study not only provides mechanistic insight into the regulation of YAP/TAZ subcellular localization, but it also strongly suggests that the miR30c–MAML–YAP/TAZ axis is a potential therapeutic target for developing novel cancer treatments.

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Regulation of Hippo pathway by Hsp70-Bag3 complex: Bag3 modulates YAP phosphorylation and its nuclear translocation

Journal of Cell Science ◽

10.1242/jcs.259107 ◽

2021 ◽

Author(s):

Simone Baldan ◽

Anatoli B. Meriin ◽

Julia Yaglom ◽

Ilya Alexandrov ◽

Xaralabos Varelas ◽

...

Keyword(s):

Protein Misfolding ◽

Nuclear Translocation ◽

Hippo Pathway ◽

Adaptive Responses ◽

Downstream Target ◽

Proteotoxic Stress ◽

Stress Signals ◽

As Stress ◽

Misfolding Diseases ◽

The Hippo Pathway

Protein abnormalities can accelerate aging causing protein misfolding diseases, various adaptive responses have evolved to relieve proteotoxicity. To trigger these responses, cells must detect the buildup of aberrant proteins. Previously we demonstrated that the Hsp70-Bag3 (HB) complex senses the accumulation of defective ribosomal products, stimulating signaling pathways, such as stress kinases or the Hippo pathway kinase LATS1. Here, we studied how Bag3 regulates the ability for LATS1 to regulate its key downstream target YAP. In naïve cells, Bag3 recruited a complex of LATS1, YAP, and the scaffold AmotL2, which links LATS1 and YAP. Upon inhibition of proteasome, AmotL2 dissociated from Bag3, which prevented phosphorylation of YAP by LATS1 and led to consequent nuclear YAP localization together with Bag3. Mutations in Bag3 that enhanced its translocation into nucleus, also facilitated nuclear translocation of YAP. Interestingly, Bag3 also controlled YAP nuclear localization in response to cell density, indicating broader roles beyond proteotoxic signaling responses for Bag3 in the regulation of YAP. These data implicate Bag3 as a regulator of Hippo pathway signaling, and suggest mechanisms by which proteotoxic stress signals are propagated.

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TGF-β Targets the Hippo Pathway Scaffold RASSF1A to Facilitate YAP/SMAD2 Nuclear Translocation

Molecular Cell ◽

10.1016/j.molcel.2016.05.012 ◽

2016 ◽

Vol 63 (1) ◽

pp. 156-166 ◽

Cited By ~ 67

Author(s):

Dafni-Eleftheria Pefani ◽

Daniela Pankova ◽

Aswin G. Abraham ◽

Anna M. Grawenda ◽

Nikola Vlahov ◽

...

Keyword(s):

Nuclear Translocation ◽

Hippo Pathway ◽

The Hippo Pathway

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p190 RhoGAP promotes contact inhibition in epithelial cells by repressing YAP activity

The Journal of Cell Biology ◽

10.1083/jcb.201710058 ◽

2018 ◽

Vol 217 (9) ◽

pp. 3183-3201 ◽

Cited By ~ 8

Author(s):

Scott R. Frank ◽

Clemens P. Köllmann ◽

Phi Luong ◽

Giorgio G. Galli ◽

Lihua Zou ◽

...

Keyword(s):

Tumor Suppressor ◽

Epithelial Cells ◽

Nuclear Translocation ◽

Hippo Pathway ◽

Contact Inhibition ◽

Tumor Suppressor Function ◽

Suppressor Function ◽

Expression Of Genes ◽

P190 Rhogap ◽

The Hippo Pathway

ARHGAP35 encoding p190A RhoGAP is a cancer-associated gene with a mutation spectrum suggestive of a tumor-suppressor function. In this study, we demonstrate that loss of heterozygosity for ARHGAP35 occurs in human tumors. We sought to identify tumor-suppressor capacities for p190A RhoGAP (p190A) and its paralog p190B in epithelial cells. We reveal an essential role for p190A and p190B to promote contact inhibition of cell proliferation (CIP), a function that relies on RhoGAP activity. Unbiased mRNA sequencing analyses establish that p190A and p190B modulate expression of genes associated with the Hippo pathway. Accordingly, we determine that p190A and p190B induce CIP by repressing YAP–TEAD-regulated gene transcription through activation of LATS kinases and inhibition of the Rho–ROCK pathway. Finally, we demonstrate that loss of a single p190 paralog is sufficient to elicit nuclear translocation of YAP and perturb CIP in epithelial cells cultured in Matrigel. Collectively, our data reveal a novel mechanism consistent with a tumor-suppressor function for ARHGAP35.

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