Pax3 regulates morphogenetic cell behavior in vitro coincident with activation of a PCP/non-canonical Wnt-signaling cascade

2002 ◽  
Vol 115 (3) ◽  
pp. 531-541 ◽  
Author(s):  
O'Neil Wiggan ◽  
Paul A. Hamel
Keyword(s):  
Wnt Signaling ◽  
Planar Cell Polarity ◽  
Molecular Mechanisms ◽  
Cell Aggregation ◽  
Signaling Cascade ◽  
Cell Behavior ◽  
Convergent Extension ◽  
Morphological Defects ◽  
Cell Fractions

Mutations to Pax3 and other Pax family genes in both mice and humans result in numerous tissue-specific morphological defects. Little is known, however, about the cellular and molecular mechanisms by which Pax genes regulate morphogenesis. We previously showed that Pax3 induces cell aggregation and a mesenchymal-to-epithelial transition in Saos-2 cells. We show here that Pax3-induced aggregates arise through the formation of distinct structures involving cell rearrangements and cell behaviors resembling those that occur during gastrulation and neurulation known as convergent extension. During these Pax3-induced processes, Dishevelled and Frizzled are localized to the actin cytoskeleton and both proteins coimmunoprecipitate focal adhesion components from detergent-insoluble cell fractions. We show further that these Pax3-induced cell movements are associated with activation of a Wnt-signaling cascade, resulting in induction and activation of c-Jun-N-terminal kinase/stress activated protein kinase (JNK/SAPK). All of these Wnt-signaling factors exhibit altered subcellular distribution in Pax3-expressing cells. In particular, we show the localization of JNK/SAPK to both the nucleus and to cytoplasmic multi-vesicular structures. These data show that Pax3 regulates morphogenetic cell behavior and that regulation of a conserved, planar cell polarity/noncanonical Wnt-signaling cascade entailing JNK activation is a function of Pax3 activity.

NOR1 Regulates Morphogenetic Cell Behavior in vitro Coincident With Inhibition of a Non-canonical Wnt-signaling Cascade*

2012 ◽  
Vol 39 (9) ◽  
pp. 887-892 ◽  
Author(s):  
Bo XIANG ◽  
Wei WANG ◽  
Wen-Juan LI ◽  
Ke TANG ◽  
Zhao-Yang ZENG ◽  
...  
Keyword(s):  
Wnt Signaling ◽  
Signaling Cascade ◽  
Cell Behavior ◽  
Canonical Wnt Signaling ◽  
Canonical Wnt

scholarly journals The oxidative stress response regulates DKK1 expression through the JNK signaling cascade in multiple myeloma plasma cells

Blood ◽  
2007 ◽  
Vol 109 (10) ◽  
pp. 4470-4477 ◽  
Author(s):  
Simona Colla ◽  
Fenghuang Zhan ◽  
Wei Xiong ◽  
Xiaosong Wu ◽  
Hongwei Xu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Multiple Myeloma ◽  
Wnt Signaling ◽  
Plasma Cells ◽  
Cell Types ◽  
Signaling Cascade ◽  
Jnk Pathway ◽  
Jnk Signaling ◽  
Dkk1 Expression

Abstract Multiple myeloma (MM) plasma cells, but not those from healthy donors and patients with monoclonal gammopathy of undetermined significance or other plasma cell dyscrasias involving the bone marrow, express the Wnt-signaling antagonist DKK1. We previously reported that secretion of DKK1 by MM cells likely contributes to osteolytic lesions in this disease by inhibiting Wnt signaling, which is essential for osteoblast differentiation and survival. The mechanisms responsible for activation and regulation of DKK1 expression in MM are not known. Herein, we could trace DKK1 expression changes in MM cells to perturbations in the JNK signaling cascade, which is differentially modulated through oxidative stress and interactions between MM cells with osteoclasts in vitro. Despite its role as a tumor suppressor and mediator of apoptosis in other cell types including osteoblasts, our data suggest that DKK1, a stress-responsive gene in MM, does not mediate apoptotic signaling, is not activated by TP53, and its forced overexpression could not inhibit cell growth or sensitize MM cells to apoptosis following treatment with thalidomide or lenalidomide. We conclude that specific strategies to modulate persistent activation of the JNK pathway may be beneficial in preventing disease progression and treating myeloma-associated bone disease by inhibiting DKK1 expression.

scholarly journals Shaking culture enhances chondrogenic differentiation of mouse induced pluripotent stem cell constructs

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Phoonsuk Limraksasin ◽  
Yukihiro Kosaka ◽  
Maolin Zhang ◽  
Naohiro Horie ◽  
Takeru Kondo ◽  
...  
Keyword(s):  
Stem Cell ◽  
Wnt Signaling ◽  
Pluripotent Stem Cell ◽  
Chondrogenic Differentiation ◽  
Induced Pluripotent Stem Cell ◽  
Immunohistochemical Analysis ◽  
Cell Aggregation ◽  
Marker Genes ◽  
Induced Pluripotent

Abstract Mechanical loading on articular cartilage induces various mechanical stresses and strains. In vitro hydrodynamic forces such as compression, shear and tension impact various cellular properties including chondrogenic differentiation, leading us to hypothesize that shaking culture might affect the chondrogenic induction of induced pluripotent stem cell (iPSC) constructs. Three-dimensional mouse iPSC constructs were fabricated in a day using U-bottom 96-well plates, and were subjected to preliminary chondrogenic induction for 3 days in static condition, followed by chondrogenic induction culture using a see-saw shaker for 17 days. After 21 days, chondrogenically induced iPSC (CI-iPSC) constructs contained chondrocyte-like cells with abundant ECM components. Shaking culture significantly promoted cell aggregation, and induced significantly higher expression of chondrogenic-related marker genes than static culture at day 21. Immunohistochemical analysis also revealed higher chondrogenic protein expression. Furthemore, in the shaking groups, CI-iPSCs showed upregulation of TGF-β and Wnt signaling-related genes, which are known to play an important role in regulating cartilage development. These results suggest that shaking culture activates TGF-β expression and Wnt signaling to promote chondrogenic differentiation in mouse iPSCs in vitro. Shaking culture, a simple and convenient approach, could provide a promising strategy for iPSC-based cartilage bioengineering for study of disease mechanisms and new therapies.

scholarly journals The Extracellular Domain of Lrp5/6 Inhibits Noncanonical Wnt Signaling In Vivo

2009 ◽  
Vol 20 (3) ◽  
pp. 924-936 ◽  
Author(s):  
Vitezslav Bryja ◽  
Emma R. Andersson ◽  
Alexandra Schambony ◽  
Milan Esner ◽  
Lenka Bryjová ◽  
...  
Keyword(s):  
Wnt Signaling ◽  
Signaling Pathways ◽  
Extracellular Domain ◽  
Convergent Extension ◽  
Mouse Development ◽  
Downstream Target ◽  
Extracellular Domains ◽  
Antisense Morpholino

Lrp5/6 are crucial coreceptors for Wnt/β-catenin signaling, a pathway biochemically distinct from noncanonical Wnt signaling pathways. Here, we examined the possible participation of Lrp5/6 in noncanonical Wnt signaling. We found that Lrp6 physically interacts with Wnt5a, but that this does not lead to phosphorylation of Lrp6 or activation of the Wnt/β-catenin pathway. Overexpression of Lrp6 blocks activation of the Wnt5a downstream target Rac1, and this effect is dependent on intact Lrp6 extracellular domains. These results suggested that the extracellular domain of Lrp6 inhibits noncanonical Wnt signaling in vitro. In vivo, Lrp6−/− mice exhibited exencephaly and a heart phenotype. Surprisingly, these defects were rescued by deletion of Wnt5a, indicating that the phenotypes resulted from noncanonical Wnt gain-of-function. Similarly, Lrp5 and Lrp6 antisense morpholino-treated Xenopus embryos exhibited convergent extension and heart phenotypes that were rescued by knockdown of noncanonical XWnt5a and XWnt11. Thus, we provide evidence that the extracellular domains of Lrp5/6 behave as physiologically relevant inhibitors of noncanonical Wnt signaling during Xenopus and mouse development in vivo.

scholarly journals IL-17B/IL-17RB signaling cascade contributes to self-renewal and tumorigenesis of cancer stem cells by regulating Beclin-1 ubiquitination

Oncogene ◽  
2021 ◽  
Author(s):  
Qingli Bie ◽  
Hui Song ◽  
Xinke Chen ◽  
Xiao Yang ◽  
Shuo Shi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Molecular Mechanisms ◽  
Tumor Necrosis Factor Receptor ◽  
Beclin 1 ◽  
Signaling Cascade ◽  
Interleukin 17 ◽  
Self Renewal

AbstractCancer stem cells (CSCs) are characterized by robust self-renewal and tumorigenesis and are responsible for metastasis, drug resistance, and angiogenesis. However, the molecular mechanisms for the regulation of CSC homeostasis are incompletely understood. This study demonstrated that the interleukin-17 (IL-17)B/IL-17RB signaling cascade promotes the self-renewal and tumorigenesis of CSCs by inducing Beclin-1 ubiquitination. We found that IL-17RB expression was significantly upregulated in spheroid cells and Lgr5-positive cells from the same tumor tissues of patients with gastric cancer (GC), which was closely correlated with the degree of cancer cell differentiation. Recombinant IL-17B (rIL-17B) promoted the sphere-formation ability of CSCs in vitro and enhanced tumor growth and metastasis in vivo. Interestingly, IL-17B induced autophagosome formation and cleavage-mediated transformation of LC3 in CSCs and 293T cells. Furthermore, inhibition of autophagy activation by ATG7 knockdown reversed rIL-17B-induced self-renewal of GC cells. In addition, we showed that IL-17B also promoted K63-mediated ubiquitination of Beclin-1 by mediating the binding of tumor necrosis factor receptor-associated factor 6 to Beclin-1. Silencing IL-17RB expression abrogated the effects of IL-17B on Beclin-1 ubiquitination and autophagy activation in GC cells. Finally, we showed that IL-17B level in the serum of GC patients was positively correlated with IL-17RB expression in GC tissues, and IL-17B could induce IL-17RB expression in GC cells. Overall, the results elucidate the novel functions of IL-17B for CSCs and suggest that the intervention of the IL-17B/IL-17RB signaling pathway may provide new therapeutic targets for the treatment of cancer.

TheXenopusreceptor tyrosine kinase Xror2 modulates morphogenetic movements of the axial mesoderm and neuroectoderm via Wnt signaling

Development ◽  
2002 ◽  
Vol 129 (22) ◽  
pp. 5227-5239 ◽  
Author(s):  
Hiroki Hikasa ◽  
Mikihito Shibata ◽  
Ichiro Hiratani ◽  
Masanori Taira
Keyword(s):  
Tyrosine Kinase ◽  
Wnt Signaling ◽  
Cell Polarity ◽  
Planar Cell Polarity ◽  
Dominant Negative ◽  
Treated Animal ◽  
Convergent Extension ◽  
Wild Type ◽  
Morphogenetic Movements ◽  
Planar Cell Polarity Pathway

The Spemann organizer plays a central role in neural induction, patterning of the neuroectoderm and mesoderm, and morphogenetic movements during early embryogenesis. By seeking genes whose expression is activated by the organizer-specific LIM homeobox gene Xlim-1 in Xenopusanimal caps, we isolated the receptor tyrosine kinase Xror2. Xror2 is expressed initially in the dorsal marginal zone, then in the notochord and the neuroectoderm posterior to the midbrain-hindbrain boundary. mRNA injection experiments revealed that overexpression of Xror2 inhibits convergent extension of the dorsal mesoderm and neuroectoderm in whole embryos, as well as the elongation of animal caps treated with activin, whereas it does not appear to affect cell differentiation of neural tissue and notochord. Interestingly, mutant constructs in which the kinase domain was point-mutated or deleted (named Xror2-TM) also inhibited convergent extension, and did not counteract the wild-type, suggesting that the ectodomain of Xror2 per se has activities that may be modulated by the intracellular domain. In relation to Wnt signaling for planar cell polarity, we observed: (1) the Frizzled-like domain in the ectodomain is required for the activity of wild-type Xror2 and Xror2-TM; (2) co-expression of Xror2 with Xwnt11, Xfz7, or both,synergistically inhibits convergent extension in embryos; (3) inhibition of elongation by Xror2 in activin-treated animal caps is reversed by co-expression of a dominant negative form of Cdc42 that has been suggested to mediate the planar cell polarity pathway of Wnt; and (4) the ectodomain of Xror2 interacts with Xwnts in co-immunoprecipitation experiments. These results suggest that Xror2 cooperates with Wnts to regulate convergent extension of the axial mesoderm and neuroectoderm by modulating the planar cell polarity pathway of Wnt.

scholarly journals Evolutionary Turnover in Wnt Gene Expression but Conservation of Wnt Signaling during Ovary Determination in a TSD Reptile

2021 ◽  
pp. 1-22
Author(s):  
Turk Rhen ◽  
Zachary Even ◽  
Alaina Brenner ◽  
Alexandra Lodewyk ◽  
Debojyoti Das ◽  
...  
Keyword(s):  
Sex Determination ◽  
Wnt Signaling ◽  
Planar Cell Polarity ◽  
Target Genes ◽  
Calcium Release ◽  
Canonical Wnt Signaling ◽  
Snapping Turtle ◽  
Canonical Wnt

Temperature-dependent sex determination (TSD) is a well-known characteristic of many reptilian species. However, the molecular processes linking ambient temperature to determination of gonad fate remain hazy. Here, we test the hypothesis that Wnt expression and signaling differ between female- and male-producing temperatures in the snapping turtle <i>Chelydra serpentina</i>. Canonical Wnt signaling involves secretion of glycoproteins called WNTs, which bind to and activate membrane bound receptors that trigger β-catenin stabilization and translocation to the nucleus where β-catenin interacts with TCF/LEF transcription factors to regulate expression of Wnt targets. Non-canonical Wnt signaling occurs via 2 pathways that are independent of β-catenin: one involves intracellular calcium release (the Wnt/Ca<sup>2+</sup> pathway), while the other involves activation of RAC1, JNK, and RHOA (the Wnt/planar cell polarity pathway). We screened 20 Wnt genes for differential expression between female- and male-producing temperatures during sex determination in the snapping turtle. Exposure of embryos to the female-producing temperature decreased expression of 7 Wnt genes but increased expression of 2 Wnt genes and <i>Rspo1</i> relative to embryos at the male-producing temperature. Temperature also regulated expression of putative Wnt target genes in vivo and a canonical Wnt reporter (6x TCF/LEF sites drive H2B-GFP expression) in embryonic gonadal cells in vitro. Results indicate that Wnt signaling was higher at the female- than at the male-producing temperature. Evolutionary analyses of all 20 Wnt genes revealed that thermosensitive Wnts, as opposed to insensitive Wnts, were less likely to show evidence of positive selection and experienced stronger purifying selection within TSD species.

scholarly journals Functional and biochemical interactions of Wnts with FrzA, a secreted Wnt antagonist

Development ◽  
1998 ◽  
Vol 125 (23) ◽  
pp. 4767-4776 ◽  
Author(s):  
Q. Xu ◽  
P.A. D'Amore ◽  
S.Y. Sokol
Keyword(s):  
Wnt Signaling ◽  
Sequence Similarity ◽  
Large Family ◽  
Early Response ◽  
Otic Vesicle ◽  
Convergent Extension ◽  
Embryonic Axes ◽  
Transmembrane Receptors ◽  
Developing Heart

Wnts are highly conserved developmental regulators that mediate inductive signaling between neighboring cells and participate in the determination of embryonic axes. Frizzled proteins constitute a large family of putative transmembrane receptors for Wnt signals. FrzA is a novel protein that shares sequence similarity with the extracellular domain of Frizzled. The Xenopus homologue of FrzA is dynamically regulated during early development. At the neurula stages, XfrzA mRNA is abundant in the somitic mesoderm, but later becomes strongly expressed in developing heart, neural crest derivatives, endoderm, otic vesicle and other sites of organogenesis. To evaluate possible biological functions of FrzA, we analyzed its effect on early Xenopus development. Microinjection of bovine or Xenopus FrzA mRNA into dorsal blastomeres resulted in a shortened body axis, suggesting a block of convergent extension movements. Consistent with this possibility, FrzA blocked elongation of ectodermal explants in response to activin, a potent mesoderm-inducing factor. FrzA inhibited induction of secondary axes by Xwnt8 and human Wnt2, but not by Xdsh, supporting the idea that FrzA interferes with Wnt signaling. Furthermore, FrzA suppressed Wnt-dependent activation of the early response genes in ectodermal explants and in the marginal zone. Finally, immunoprecipitation experiments demonstrate that FrzA binds to the soluble Wingless protein in cell culture supernatants in vitro. Our results indicate that FrzA is a naturally occurring secreted antagonist of Wnt signaling.

scholarly journals Quantitative Analysis of Cell Aggregation Dynamics Identifies HDAC Inhibitors as Potential Regulators of Cancer Cell Clustering

Cancers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 5840
Author(s):  
Fabien Gava ◽  
Julie Pignolet ◽  
Sébastien Déjean ◽  
Odile Mondésert ◽  
Renaud Morin ◽  
...  
Keyword(s):  
Tumor Cell ◽  
Cell Lines ◽  
Cancer Cell ◽  
Molecular Mechanisms ◽  
Hdac Inhibitors ◽  
Cell Aggregation ◽  
Initial Step ◽  
Transcriptional Signature ◽  
Cell Clustering

Characterization of the molecular mechanisms involved in tumor cell clustering could open the way to new therapeutic strategies. Towards this aim, we used an in vitro quantitative procedure to monitor the anchorage-independent cell aggregation kinetics in a panel of 25 cancer cell lines. The analysis of the relationship between selected aggregation dynamic parameters and the gene expression data for these cell lines from the CCLE database allowed identifying genes with expression significantly associated with aggregation parameter variations. Comparison of these transcripts with the perturbagen signatures from the Connectivity Map resource highlighted that they were strongly correlated with the transcriptional signature of most histone deacetylase (HDAC) inhibitors. Experimental evaluation of two HDAC inhibitors (SAHA and ISOX) showed that they inhibited the initial step of in vitro tumor cell aggregation. This validates our findings and reinforces the potential interest of HDCA inhibitors to prevent metastasis spreading.

High resolution mapping of nucleic acid containing complexes in vitro and in situ

1996 ◽  
Vol 54 ◽  
pp. 48-49
Author(s):  
D. P. Bazett-Jones ◽  
M. J. Hendzel
Keyword(s):  
Nucleic Acid ◽  
High Resolution ◽  
Transcription Initiation ◽  
Molecular Mechanisms ◽  
Heavy Atom ◽  
Regulation Of Transcription ◽  
High Exposure ◽  
Resolution Mapping ◽  
Tata Sequence

Structural analysis of combinations of nucleosomes and transcription factors on promoter and enhancer elements is necessary in order to understand the molecular mechanisms responsible for the regulation of transcription initiation. Such complexes are often not amenable to study by high resolution crystallographic techniques. We have been applying electron spectroscopic imaging (ESI) to specific problems in molecular biology related to transcription regulation. There are several advantages that this technique offers in studies of nucleoprotein complexes. First, an intermediate level of spatial resolution can be achieved because heavy atom contrast agents are not necessary. Second, mass and stoichiometric relationships of protein and nucleic acid can be estimated by phosphorus detection, an element in much higher proportions in nucleic acid than protein. Third, wrapping or bending of the DNA by the protein constituents can be observed by phosphorus mapping of the complexes. Even when ESI is used with high exposure of electrons to the specimen, important macromolecular information may be provided. For example, an image of the TATA binding protein (TBP) bound to DNA is shown in the Figure (top panel). It can be seen that the protein distorts the DNA away from itself and much of its mass sits off the DNA helix axis. Moreover, phosphorus and mass estimates demonstrate whether one or two TBP molecules interact with this particular promoter TATA sequence.

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