scholarly journals B-Cell Translocation Gene 2 (Btg2) Regulates Vertebral Patterning by Modulating Bone Morphogenetic Protein/Smad Signaling

2004 ◽  
Vol 24 (23) ◽  
pp. 10256-10262 ◽  
Author(s):  
Sean Park ◽  
Young Jae Lee ◽  
Ho-Jae Lee ◽  
Tsugio Seki ◽  
Kwon-Ho Hong ◽  
...  
Keyword(s):  
Bone Morphogenetic Protein ◽  
Target Gene ◽  
Bmp Signaling ◽  
Dependent Manner ◽  
Tail Bud ◽  
Adaptor Molecule ◽  
Morphogenetic Protein ◽  
Dose Dependent ◽  
Transcriptional Target

ABSTRACT Btg2 is a primary p53 transcriptional target gene which may function as a coactivator-corepressor and/or an adaptor molecule that modulates the activities of its interacting proteins. We have generated Btg2-null mice to elucidate the in vivo function of Btg2. Btg2-null mice are viable and fertile but exhibit posterior homeotic transformations of the axial vertebrae in a dose-dependent manner. Consistent with its role in vertebral patterning, Btg2 is expressed in the presomitic mesoderm, tail bud, and somites during somitogenesis. We further provide biochemical evidence that Btg2 interacts with bone morphogenetic protein (BMP)-activated Smads and enhances the transcriptional activity of BMP signaling. In view of the genetic evidence that reduced BMP signaling causes posteriorization of the vertebral pattern, we propose that the observed vertebral phenotype in Btg2-null mice is due to attenuated BMP signaling.

Mechanisms of dorsal-ventral patterning in noggin-induced neural tissue

Development ◽  
1997 ◽  
Vol 124 (12) ◽  
pp. 2477-2488 ◽  
Author(s):  
A.K. Knecht ◽  
R.M. Harland
Keyword(s):  
Neural Tissue ◽  
Bmp Signaling ◽  
Cell Interactions ◽  
Dependent Manner ◽  
Low Doses ◽  
Morphogenetic Protein ◽  
High Doses ◽  
Dose Dependent ◽  
Cell Cell

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.

scholarly journals Use of Bmp1/Tll1 Doubly Homozygous Null Mice and Proteomics To Identify and Validate In Vivo Substrates of Bone Morphogenetic Protein 1/Tolloid-Like Metalloproteinases

2003 ◽  
Vol 23 (13) ◽  
pp. 4428-4438 ◽  
Author(s):  
William N. Pappano ◽  
Barry M. Steiglitz ◽  
Ian C. Scott ◽  
Douglas R. Keene ◽  
Daniel S. Greenspan
Keyword(s):  
Bone Morphogenetic Protein ◽  
Residual Activity ◽  
Functional Redundancy ◽  
Bmp Signaling ◽  
Null Mouse ◽  
Genetic Redundancy ◽  
Morphogenetic Protein ◽  
Bone Morphogenetic Protein 1

ABSTRACT Bone morphogenetic protein 1 (BMP-1) and mammalian Tolloid (mTLD), two proteinases encoded by Bmp1, provide procollagen C-proteinase (pCP) activity that converts procollagens I to III into the major fibrous components of mammalian extracellular matrix (ECM). Yet, although Bmp1 −/− mice have aberrant collagen fibrils, they have residual pCP activity, indicative of genetic redundancy. Mammals possess two additional proteinases structurally similar to BMP-1 and mTLD: the genetically distinct mammalian Tolloid-like 1 (mTLL-1) and mTLL-2. Mice lacking the mTLL-1 gene Tll1 are embryonic lethal but have pCP activity levels similar to those of the wild type, suggesting that mTLL-1 might not be an in vivo pCP. In vitro studies have shown BMP-1 and mTLL-1 capable of cleaving Chordin, an extracellular antagonist of BMP signaling, suggesting that these proteases might also serve to modulate BMP signaling and to coordinate the latter with ECM formation. However, in vivo evidence of roles for BMP-1 and mTLL-1 in BMP signaling in mammals is lacking. To remove functional redundancy obscuring the in vivo functions of BMP-1-related proteases in mammals, we here characterize Bmp1 Tll1 doubly null mouse embryos. Although these appear morphologically indistinguishable from Tll1 −/− embryos, biochemical analysis of cells derived from doubly null embryos shows functional redundancy removed to an extent enabling us to demonstrate that (i) products of Bmp1 and Tll1 are responsible for in vivo cleavage of Chordin in mammals and (ii) mTLL-1 is an in vivo pCP that provides residual activity observed in Bmp1 −/− embryos. Removal of functional redundancy also enabled use of Bmp1 −/− Tll1 −/− cells in a proteomics approach for identifying novel substrates of Bmp1 and Tll1 products.

scholarly journals Smad-Dependent Recruitment of a Histone Deacetylase/Sin3A Complex Modulates the Bone Morphogenetic Protein-Dependent Transcriptional Repressor Activity of Nkx3.2

2003 ◽  
Vol 23 (23) ◽  
pp. 8704-8717 ◽  
Author(s):  
Dae-Won Kim ◽  
Andrew B. Lassar
Keyword(s):  
Transcription Factor ◽  
Bone Morphogenetic Protein ◽  
Histone Deacetylase ◽  
Transcriptional Activation ◽  
Transcriptional Repressor ◽  
Bmp Signaling ◽  
Dependent Manner ◽  
Histone Deacetylase 1 ◽  
Morphogenetic Protein ◽  
Repressor Activity

ABSTRACT We have previously shown that Nkx3.2, a transcriptional repressor that is expressed in the sclerotome and developing cartilage, can activate the chondrocyte differentiation program in somitic mesoderm in a bone morphogenetic protein (BMP)-dependent manner. In this work, we elucidate how BMP signaling modulates the transcriptional repressor activity of Nkx3.2. We have found that Nkx3.2 forms a complex, in vivo, with histone deacetylase 1 (HDAC1) and Smad1 and -4 in a BMP-dependent manner. The homeodomain and NK domain of Nkx3.2 support the interaction of this transcription factor with HDAC1 and Smad1, respectively, and both of these domains are required for the transcriptional repressor activity of Nkx3.2. Furthermore, the recruitment of an HDAC/Sin3A complex to Nkx3.2 requires that Nkx3.2 interact with Smad1 and -4. Indeed, Nkx3.2 both fails to associate with the HDAC/Sin3A complex and represses target gene transcription in a cell line lacking Smad4, but it performs these functions if exogenous Smad4 is added to these cells. While prior work has indicated that BMP-dependent Smads can support transcriptional activation, our findings indicate that BMP-dependent Smads can also potentiate transcriptional repression, depending upon the identity of the Smad-interacting transcription factor.

scholarly journals Bone morphogenetic protein 2 inhibits growth differentiation factor 8-induced cell signaling via upregulation of gremlin2 expression in human granulosa-lutein cells

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xiaoyan Luo ◽  
Hsun-Ming Chang ◽  
Yuyin Yi ◽  
Yingpu Sun ◽  
Peter C. K. Leung
Keyword(s):  
Bone Morphogenetic Protein ◽  
Molecular Mechanisms ◽  
Kinase Inhibitors ◽  
Bmp Signaling ◽  
Bone Morphogenetic Protein 2 ◽  
Type I ◽  
Dependent Manner ◽  
Small Interfering Rnas ◽  
Differentiation Factor ◽  
Morphogenetic Protein

Abstract Background Bone morphogenetic protein 2 (BMP2), growth differentiation factor 8 (GDF8) and their functional receptors are expressed in human ovarian follicles, and these two intrafollicular factors play essential roles in regulating follicle development and luteal function. As BMP antagonists, gremlin1 (GREM1) and gremlin2 (GREM2) suppress BMP signaling through blockage of ligand-receptor binding. However, whether BMP2 regulates the expression of GREM1 and GREM2 in follicular development remains to be determined. Methods In the present study, we investigated the effect of BMP2 on the expression of GREM1 and GREM2 and the underlying mechanisms in human granulosa-lutein (hGL) cells. An established immortalized human granulosa cell line (SVOG) and primary hGL cells were used as study models. The expression of GREM1 and GREM2 were examined following cell incubation with BMP2 at different concentrations and time courses. The TGF-β type I inhibitors (dorsomorphin, DMH-1 and SB431542) and small interfering RNAs targeting ALK2, ALK3, SMAD2/3, SMAD1/5/8 and SMAD4 were used to investigate the involvement of the SMAD-dependent pathway. Results Our results showed that BMP2 significantly increased the expression of GREM2 (but not GREM1) in a dose- and time-dependent manner. Using a dual inhibition approach combining kinase inhibitors and siRNA-mediated knockdown, we found that the BMP2-induced upregulation of GREM2 expression was mediated by the ALK2/3-SMAD1/5-SMAD4 signaling pathway. Moreover, we demonstrated that BMP2 pretreatment significantly attenuated the GDF8-induced phosphorylation of SMAD2 and SMAD3, and this suppressive effect was reversed by knocking down GREM2 expression. Conclusions Our findings provide new insight into the molecular mechanisms by which BMP2 modulates the cellular activity induced by GDF8 through the upregulated expression of their antagonist (GREM2).

scholarly journals Activation of the Bone Morphogenetic Protein Signaling Pathway Induces Inhibin βB-Subunit mRNA and Secreted Inhibin B Levels in Cultured Human Granulosa-Luteal Cells

2002 ◽  
Vol 87 (3) ◽  
pp. 1254-1261 ◽  
Author(s):  
Risto Jaatinen ◽  
Jonas Bondestam ◽  
Taneli Raivio ◽  
Kristiina Hildén ◽  
Leo Dunkel ◽  
...  
Keyword(s):  
Bone Morphogenetic Protein ◽  
Signaling Pathway ◽  
Granulosa Cell ◽  
Bmp Signaling ◽  
Inhibin B ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Subunit Mrna ◽  
Morphogenetic Protein

During the human menstrual cycle the circulating levels of inhibin B, a dimer of inhibin α- and βB-subunits, fluctuate in a fashion distinct from that of inhibin A, the α-βA-subunit dimer. This suggests that human inhibin subunits are each regulated in a distinct manner in human ovarian granulosa cells by endocrine and local factors. We have previously shown using cultures of human granulosa-luteal (hGL) cells that gonadotropins stimulate the steady state mRNA levels of inhibin α- and βA-subunits, but not those of the βB-subunit, which, on the other hand, are up-regulated by, for instance, activin and TGFβ. We recently identified the TGFβ gene family member bone morphogenetic protein-3 (BMP-3) as a granulosa cell-derived growth factor, but whether BMP-3 or other structurally related BMPs regulate human granulosa cell inhibin production is not known. We show here that hGL cells express mRNAs for distinct serine/threonine kinase receptors (BMP-RIA and BMP-RII) and Smad signaling proteins (Smad1, Smad4, and Smad5) involved in the mediation of cellular effects of BMPs. Subsequently, we determined in hGL cell cultures the effects of distinct members of the BMP family previously found to be expressed in mammalian ovaries. Recombinant BMP-2 induces potently in a time- and concentration-dependent manner the expression of the inhibin βB-subunit mRNAs in hGL cells without affecting the levels of α- or βA-subunit mRNAs. BMP-6 has a similar, but weaker, effect than BMP-2, whereas BMP-3 and its close homolog, BMP-3b (also known as growth differentiation factor-10) had no effect on inhibin subunit mRNA expression. hCG treatment of hGL cells was previously shown to abolish the stimulatory effect of activin on βB-subunit mRNA levels, and here hCG is also shown to suppress the effect of BMP-2. Furthermore, BMP-2 stimulates hGL cell secreted dimeric inhibin B levels in a concentration-dependent manner. Depending on the experiment, maximal increases in inhibin B levels of 6- to 28-fold above basal levels were detected during a 72-h culture period. We conclude that activation of the BMP-signaling pathway in hGL cells stimulates inhibin βB-subunit mRNA levels and leads at the protein level to a dramatic stimulation of secreted inhibin B dimers. Our results are consistent with the suggestion that in addition to the distinct activin- and TGFβ-activated signaling pathways, the BMP-activated pathway is likely to be implicated in the complex regulation of inhibins in the human ovary.

Expression, signalling and potential in vivo functions of Bone Morphogenetic Protein (BMP)-9 in the liver

2009 ◽  
Vol 47 (01) ◽  
Author(s):  
K Breitkopf ◽  
A Müller ◽  
L Ciuclan ◽  
E Wiercinska ◽  
P ten Dijke ◽  
...  
Keyword(s):  
Bone Morphogenetic Protein ◽  
Morphogenetic Protein

Effects of NO-Donors on Thrombus Formation and Microcirculation in Cerebral Vessels of the Rat

1996 ◽  
Vol 76 (01) ◽  
pp. 111-117 ◽  
Author(s):  
Yasuto Sasaki ◽  
Junji Seki ◽  
John C Giddings ◽  
Junichiro Yamamoto
Keyword(s):  
Blood Flow ◽  
Thrombus Formation ◽  
Dependent Manner ◽  
Red Cell ◽  
Cell Velocity ◽  
Red Cell Velocity ◽  
The Mean ◽  
Wall Shear ◽  
Dose Dependent

SummarySodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1), are known to liberate nitric oxide (NO). In this study the effects of SNP and SIN-1 on thrombus formation in rat cerebral arterioles and venules in vivo were assessed using a helium-neon (He-Ne) laser. SNP infused at doses from 10 Μg/kg/h significantly inhibited thrombus formation in a dose dependent manner. This inhibition of thrombus formation was suppressed by methylene blue. SIN-1 at a dose of 100 Μg/kg/h also demonstrated a significant antithrombotic effect. Moreover, treatment with SNP increased vessel diameter in a dose dependent manner and enhanced the mean red cell velocity measured with a fiber-optic laser-Doppler anemometer microscope (FLDAM). Blood flow, calculated from the mean red cell velocity and vessel diameters was increased significantly during infusion. In contrast, mean wall shear rates in the arterioles and venules were not changed by SNP infusion. The results indicated that SNP and SIN-1 possessed potent antithrombotic activities, whilst SNP increased cerebral blood flow without changing wall shear rate. The findings suggest that the NO released by SNP and SIN-1 may be beneficial for the treatment and protection of cerebral infarction

scholarly journals Anti-tumor activity of a novel proteasome inhibitor D395 against multiple myeloma and its lower cardiotoxicity compared with carfilzomib

2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Xuxing Shen ◽  
Chao Wu ◽  
Meng Lei ◽  
Qing Yan ◽  
Haoyang Zhang ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Proteasome Inhibitor ◽  
Osteoclast Differentiation ◽  
Dependent Manner ◽  
Serum Enzyme ◽  
Herg Channels ◽  
Anti Tumor Activity ◽  
Dose Dependent

AbstractCarfilzomib, a second-generation proteasome inhibitor, has significantly improved the survival rate of multiple myeloma (MM) patients, but its clinical application is still restricted by drug resistance and cardiotoxicity. Here, we identified a novel proteasome inhibitor, D395, and assessed its efficacy in treating MM as well as its cardiotoxicity at the preclinical level. The activities of purified and intracellular proteasomes were measured to determine the effect of D395 on the proteasome. CCK-8 and flow cytometry experiments were designed to evaluate the effects of D395 on cell growth and apoptosis. The effects of D395 and carfilzomib on serum enzyme activity, echocardiography features, cardiomyocyte morphology, and hERG channels were also compared. In our study, D395 was highly cytotoxic to MM cell lines and primary MM cells but not normal cells, and it was well tolerated in vivo. Similar to carfilzomib, D395 inhibited osteoclast differentiation in a dose-dependent manner. In particular, D395 exhibited lower cardiotoxicity than carfilzomib in all experiments. In conclusion, D395 is a novel irreversible proteasome inhibitor that has remarkable anti-MM activity and mild cardiotoxicity in vitro and in vivo.

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