scholarly journals CD44 modulates Smad1 activation in the BMP-7 signaling pathway

2004 ◽  
Vol 166 (7) ◽  
pp. 1081-1091 ◽  
Author(s):  
Richard S. Peterson ◽  
Roma A. Andhare ◽  
Kathleen T. Rousche ◽  
Warren Knudson ◽  
Weihua Wang ◽  
...  

Bone morphogenetic protein 7 (BMP-7) regulates cellular metabolism in embryonic and adult tissues. Signal transduction occurs through the activation of intracellular Smad proteins. In this paper, using a yeast two-hybrid screen, Smad1 was found to interact with the cytoplasmic domain of CD44, a receptor for the extracellular matrix macromolecule hyaluronan. Coimmunoprecipitation experiments confirmed the interaction of Smad1 with full-length CD44—interactions that did not occur when CD44 receptors truncated within the cytoplasmic domain were tested. Chondrocytes overexpressing a truncated CD44 on a background of endogenous full-length CD44 no longer exhibited Smad1 nuclear translocation upon BMP-7 stimulation. Further, pretreatment of chondrocytes with Streptomyces hyaluronidase to disrupt extracellular hyaluronan–cell interactions inhibited BMP-7–mediated Smad1 phosphorylation, nuclear translocation of Smad1 or Smad4, and SBE4–luciferase reporter activation. These results support a functional link between the BMP signaling cascade and CD44. Thus, changes in hyaluronan–cell interactions may serve as a means to modulate cellular responsiveness to BMP.

2021 ◽  
Vol 8 (2) ◽  
pp. 57-64
Author(s):  
Fangfang Li ◽  
Peixi Qin ◽  
Lisha Ye ◽  
Nishith Gupta ◽  
Min Hu

SMAD proteins mediate TGF-β signaling and thereby regulate the metazoan development; however, they are poorly defined in Haemonchus contortus–a common blood-sucking parasitic nematode of small ruminants. Here, we characterized an R-SMAD family protein in H. contortus termed HcSMA2, which is closely related to Caenorhabditis elegans SMA2 (CeSMA2) involved in the bone morphogenetic protein (BMP) signaling. Hcsma2 is transcribed in all developmental stages of H. contortus but highly induced in the adult male worms. The RNA interference with Hcsma2 retarded the transition of infective L3 into L4 larvae. Besides, the bimolecular fluorescence complementation revealed the interaction of HcSMA2 with a TGF-β-activated-R-SMAD (HcDAF8). Together these results show a BMP-like receptor-regulated SMAD in H. contortus that is required for larval differentiation and underscore an adaptive functional repurposing of BMP-signaling in parasitic worms.


2020 ◽  
Author(s):  
Arindam Mondal ◽  
Rachel NeMoyer ◽  
Elaine Langenfeld ◽  
Danea Glover ◽  
Michael Scott ◽  
...  

Abstract Background: BMP is an evolutionary conserved morphogen that is reactivated in lung carcinomas. BMP receptor inhibitors promote cell death of lung carcinomas by mechanisms not fully elucidated. The studies here reveal novel mechanisms by which the “survivin” inhibitor Ym155 in combination with the BMP inhibitor JL5 synergistically induces death of lung cancer cells.Methods: This study examines the mechanism by which Ym155 in combination with JL5 downregulates BMP signaling and induces cell death of non-small cell lung carcinomas (NSCLC) cell lines. Validation experiments were performed on five passage 0 primary NSCLC.Results: We found that Ym155, which is reported to be a survivin inhibitor, potently inhibits BMP signaling by causing BMPR2 mislocalization into the cytoplasm and its decreased expression. Ym155 mediated cell death is not caused by the inhibition of survivin but involves Ym155 binding to mitochondrial DNA leading to depletion of ATP. The combination of Ym155 and the BMP receptor inhibitor JL5 synergistically causes the downregulation of BMP Smad-1/5 dependent and independent signaling and the induction of cell death of lung cancer cell lines and primary lung tumors. Cell death involves the nuclear translocation of apoptosis inducing factor (AIF) from the mitochondria to the nucleus causing DNA double stranded breaks independent of caspase activation, which occurs only when JL5 and Ym155 are used in combination. Knockdown of BMPR2 together with Ym155 also induced AIF localization to the nucleus.Conclusions: These studies suggest that inhibition of BMPR2 together with Ym155 can induce AIF caspase-independent cell death. AIF caspase-independent cell is an evolutionary conserved cell death pathway that has never been targeted to induce cell death in cancer cells. These studies provide mechanistic insight how to target AIF caspase-independent cell death using BMP inhibitors.


2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Pamela P Lockyer ◽  
Hua Mao ◽  
Xi Li ◽  
Xinchun Pi

Dysfunction of the vascular endothelium results in various cardiovascular, circulatory and blood diseases and exemplifies the importance of endothelial integrity. BMP-binding endothelial regulator (BMPER), a well recognized extracellular modulator of Bone morphogenetic protein (BMP) signaling, has been identified as a vital component in the vascular response to stress. Microarray analysis revealed nuclear factor of activated T cells (NFAT) as one of the genes found to be most highly upregulated by BMPER treatment in mouse endothelial cells (MECs), as well as many genes with NFAT consensus binding sites. Therefore we hypothesize that BMPER is an important regulator of NFAT transcriptional activity. Initially we have investigated the effect of BMPER on NFATc1 activation with MECs and human primary endothelial cells. Our data show that the translocation of NFATc1 from the cytoplasm to the nucleus following BMPER treatment, determined by immunofluorescent analysis. By using the nuclear fractionation assays, we observed the similar result that the translocation of NFATc1 to the nucleus of HUVECs took place after 30 minutes of BMPER treatment. Next, we wanted to determine whether the increased NFATc1 protein level in nucleus results in the enhanced transcriptional activity. Indeed, when HUVECs are treated with BMPER and then analyzed with luciferase reporter assay, a 1.5-fold significant increase in NFAT activity over baseline was observed. Our previous data demonstrate that LDL receptor related protein (LRP1) interacts with BMPER and regulates BMPER’s activity through endocytosis in endothelial cells. Interesting, we observe that LRP1 also interacts with NF45, the 45-kDa subunit of NFAT protein. It strongly suggests that BMPER positively regulates NFAT activity through LRP1. This novel signaling pathway indicates that BMPER may acts as a new ligand and exhibits BMP-independent activity in endothelial cells and therefore contribute to the regulation of vascular homeostasis.


Development ◽  
1997 ◽  
Vol 124 (12) ◽  
pp. 2477-2488 ◽  
Author(s):  
A.K. Knecht ◽  
R.M. Harland

We have investigated mechanisms of dorsal-ventral patterning of neural tissue, using Xenopus ectoderm neuralized by noggin protein. This tissue appears to be patterned dorsoventrally; cp1-1, a gene expressed in the dorsal brain, and etr-1, a gene largely excluded from the dorsal brain, are expressed in separate territories in noggin-treated explants (Knecht, A. K., Good, P. J., Dawid, I. B. and Harland, R. M. (1995) Development 121, 1927–1936). Here we show further evidence that this pattern represents a partial dorsal-ventral organization. Additionally, we test two mechanisms that could account for this pattern: a dose-dependent response to a gradient of noggin protein within the explant, and regulative cell-cell interactions. We show that noggin exhibits concentration-dependent effects, inducing cp1-1 at low doses but repressing it at high doses. Since noggin acts by antagonizing Bone Morphogenetic Protein (BMP) signaling, this result suggests that BMPs also may act in a dose-dependent manner in vivo. However, in the absence of a noggin gradient, regulative cell-cell interactions can also pattern the tissue. Such regulation is facilitated by increased motility of noggin-treated cells. Finally, the response of cells to both of these patterning mechanisms is ultimately controlled by a third process, the changing competence of the responding tissue.


2021 ◽  
Vol 22 (15) ◽  
pp. 7935
Author(s):  
Zahra Kargarpour ◽  
Jila Nasirzade ◽  
Layla Panahipour ◽  
Goran Mitulović ◽  
Richard J. Miron ◽  
...  

Solid platelet-rich fibrin (PRF), consisting of coagulated plasma from fractionated blood, has been proposed to be a suitable carrier for recombinant bone morphogenetic protein 2 (BMP2) to target mesenchymal cells during bone regeneration. However, whether solid PRF can increase the expression of BMPs in mesenchymal cells remains unknown. Proteomics analysis confirmed the presence of TGF-β1 but not BMP2 in PRF lysates. According to the existing knowledge of recombinant TGF-β1, we hypothesized that PRF can increase BMP2 expression in mesenchymal cells. To test this hypothesis, we blocked TGF-β receptor 1 kinase with SB431542 in gingival fibroblasts exposed to PRF lysates. RT-PCR and immunoassays confirmed that solid PRF lysates caused a robust SB431542-dependent increase in BMP2 expression in gingival fibroblasts. Additionally, fractions of liquid PRF, namely platelet-poor plasma (PPP) and the buffy coat (BC) layer, but not heat-denatured PPP (Alb-gel), greatly induced the expression of BMP2 in gingival fibroblasts. Even though PRF has no detectable BMPs, PRF lysates similar to recombinant TGF-β1 had the capacity to provoke canonical BMP signaling, as indicated by the nuclear translocation of Smad1/5 and the increase in its phosphorylation. Taken together, our data suggest that PRF can activate TGF-β receptor 1 kinase and consequently induce the production of BMP2 in cells of the mesenchymal lineage.


2006 ◽  
Vol 54 (4) ◽  
pp. 407-415 ◽  
Author(s):  
Tasima Haque ◽  
Manuela Mandu-Hrit ◽  
Frank Rauch ◽  
Dominique Lauzier ◽  
Maryam Tabrizian ◽  
...  

In this study we investigated the expression of bone morphogenetic protein (BMP)-signaling Smads in distraction osteogenesis (DO). Osteotomy of the right tibia was performed in 14 skeletally mature white New Zealand male rabbits. Lengthening was started 1 week later at a rate of 0.5 mm/12 hr and was maintained for 3 weeks. Expression of Smad proteins 1, 4, 5, 6, 7, and 8 and Smad ubiquitin regulatory factors (Smurfs) 1 and 2 was evaluated in the distracted zone using immunohistochemistry. Expression of receptor-regulated Smads (R-Smads) 1, 5, and 8 showed a significant increase during the distraction phase, followed by a gradual decrease during the consolidation phase. Smad 4 showed significant expression during both distraction and the beginning of the consolidation phase. Smad 6 and Smad 7 were highly expressed during the consolidation phase. Staining for both Smurfs 1 and 2 was maximal at the end of the distraction period. Staining for all proteins was most intense in chondrocyte and fibroblast-like cells. Expression pattern of R-Smads correlated with our previously reported expression pattern of BMPs 2, 4, and 7 and their receptors. These results therefore suggest a role for the whole BMP signaling pathway including the Smad proteins in DO.


2019 ◽  
Author(s):  
Uday Madaan ◽  
Lionel Faure ◽  
Albar Chowdhury ◽  
Shahrear Ahmed ◽  
Emma J. Ciccarelli ◽  
...  

AbstractCellular responsiveness to environmental cues, including changes in extracellular matrix (ECM), is critical for normal processes such as development and wound healing, but can go awry, as in oncogenesis and fibrosis. One type of molecular pathway allowing this responsiveness is the bone morphogenetic protein (BMP) signaling pathway. Due to their broad and potent functions, BMPs and their signaling pathways are highly regulated at multiple levels. In Caenorhabditis elegans, the BMP ligand DBL-1 is a major regulator of body size. We have previously shown that DBL-1/BMP signaling determines body size through transcriptional regulation of cuticle collagen genes. We have now obtained evidence of feedback regulation of DBL-1/BMP by collagen genes. We analyzed four DBL-1-regulated collagen genes that affect body size. Here we show that inactivation of any one of these cuticle collagen genes reduces DBL-1/BMP signaling, as measured by a Smad activity reporter. Furthermore, we find that depletion of these collagens reduces GFP::DBL-1 fluorescence, and acts unexpectedly at the level of dbl-1 transcription. We therefore conclude that cuticle, a type of ECM, impinges on DBL-1/BMP expression and signaling. In contrast to other characterized examples, however, the feedback regulation of DBL-1/BMP signaling by collagens is likely to be contact-independent, due to the physical separation of the cuticle from DBL-1-expressing cells in the ventral nerve cord. Our results provide an entry point into a novel mechanism of regulation of BMP signaling, with broader implications for mechanical regulation of gene expression in general.


Blood ◽  
2011 ◽  
Vol 117 (24) ◽  
pp. 6489-6497 ◽  
Author(s):  
Brandoch D. Cook ◽  
Susanna Liu ◽  
Todd Evans

Abstract Bone morphogenetic protein (BMP) signaling regulates embryonic hematopoiesis via receptor-mediated activation of downstream SMAD proteins, including SMAD1. In previous work, we showed that Smad1 expression is sufficient to enhance commitment of mesoderm to hemangioblast fate. We also found indirect evidence to support a subsequent repressive function for Smad1 in hematopoiesis. To test this hypothesis directly, we developed a novel system allowing temporal control of Smad1 levels by conditional knockdown in embryonic stem cell derivatives. Depletion of Smad1 in embryoid body cultures before hemangioblast commitment limits hematopoietic potential because of a block in mesoderm development. Conversely, when Smad1 is depleted in FlK1+ mesoderm, at a stage after hemangioblast commitment, the pool of hematopoietic progenitors is expanded. This involves enhanced expression levels for genes specific to hematopoiesis, including Gata1, Runx1 and Eklf, rather than factors required for earlier specification of the hemangioblast. The phenotype correlates with increased nuclear SMAD2 activity, indicating molecular cross-regulation between the BMP and TGF-β signaling pathways. Consistent with this mechanism, hematopoiesis was enhanced when Smad2 was directly expressed during this same developmental window. Therefore, this study reveals a temporally defined function for Smad1 in restricting the expansion of early hematopoietic progenitors.


2021 ◽  
Vol 22 (2) ◽  
pp. 694
Author(s):  
Wing-Keung Chu ◽  
Li-Man Hung ◽  
Chun-Wei Hou ◽  
Jan-Kan Chen

The Yes-associated protein (YAP) is a transcriptional co-activator that plays critical roles in organ development and tumorigenesis, and is verified to be inhibited by the Hippo signaling pathway. In the present study, we show that the YAP 3′UTR is alternatively spliced to generate a novel 950 bp 3′UTR mRNA from the full length 3′UTR region (3483 bp) in human cancer cells. The ratio of full length 3′UTR YAP mRNA to alternatively spliced 3′UTR YAP mRNA is up-regulated by exposure of the cells to PKC inhibitor chelerythrine chloride. Further study using luciferase reporter assay showed that the expression of the alternatively spliced 3′UTR mRNA is much lower compared with the full length 3′UTR mRNA, suggesting that alternatively spliced 3′UTR YAP mRNA may have a shorter half-life than full length 3′UTR mRNA. Interestingly, PKC represses YAP 3′UTR–mediated mRNA stability is dependent on a splicing factor, hnRNP F. Activation of PKC induces nuclear translocation of cytosolic hnRNP F. Ectopic expression of hnRNP F enhances YAP 3′UTR splicing. Our results suggest that hnRNP F regulates YAP 3′UTR-mediated mRNA stability in an alternative splicing-dependent manner, and PKC regulated YAP expression is dependent on nuclear translocation of hnRNP F in human cancer cell lines.


2020 ◽  
Vol 25 (45) ◽  
pp. 4806-4812 ◽  
Author(s):  
Zhibo Sun ◽  
Fei Wu ◽  
Yue Yang ◽  
Feng Liu ◽  
Fengbo Mo ◽  
...  

Background: MicroRNAs have recently been recognized to be engaged in the development of bone diseases. Objective: This study was performed to elucidate the effects of miR-144-3p on proliferation and osteogenesis of mesenchymal stem cells (MSCs) from the patients with steroid-associated osteonecrosis (ONFH) and its related mechanism. Method: The expression level of miR-144-3p in the MSCs from the proximal femur of the patients was examined by Real-time PCR. The cell proliferation ability was assayed by MTT. The differentiation ability of MSCs was assayed by Alizarin Red S (ARS) staining. The interaction between miR-144-3p and frizzled4 (FZD4) was investigated by Real-time PCR, western blot and luciferase reporter assay. Results: ONFH samples had the obviously high expression of miR-144-3p compared to the control. MiR-144-3p had a negative effect on the proliferation and osteogenesis of MSCs. Via targeting FZD4, miR-144-3p decreased β-catenin nuclear translocation, the transcription of RUNX2 and COL1A1. Over-expression of FZD4 partially reversed miR-144-3p-induced decrease in the proliferation and osteogenesis of MSCs. Conclusion: MiR-144-3p might play an important role in the development of ONFH and might be used as a novel class of therapeutic targets for this disease.


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