In vivo analysis using variants of zebrafish BMPR-IA: range of action and involvement of BMP in ectoderm patterning

Development ◽  
1999 ◽  
Vol 126 (1) ◽  
pp. 181-190 ◽  
Author(s):  
M. Nikaido ◽  
M. Tada ◽  
H. Takeda ◽  
A. Kuroiwa ◽  
N. Ueno
Keyword(s):  
Cell Fate ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Active Form ◽  
Ectopic Expression ◽  
Signal Propagation ◽  
Early Embryo ◽  
Type I ◽  
Cell Fate Conversion

It has been an intriguing problem whether the polypeptide growth factors belonging to the transforming growth factor-beta (TGF-beta) superfamily function as direct and long-range signaling molecules in pattern formation of the early embryo. In this study, we examined the mechanism of signal propagation of bone morphogenetic protein (BMP) in the ectodermal patterning of zebrafish embryos, in which BMP functions as an epidermal inducer and a neural inhibitor. To estimate the effective range of zbmp-2, we first performed whole-mount in situ hybridization analysis. The zbmp-2-expressing domain and the neuroectoderm, marked by otx-2 expression, were complementary, suggesting that BMP has a short-range effect in vivo. Moreover, mosaic experiments using a constitutively active form of a zebrafish BMP type I receptor (CA-BRIA) demonstrated that the cell-fate conversion, revealed by ectopic expression of gata-3 and repression of otx-2, occurred in a cell-autonomous manner, denying the involvement of the relay mechanism. We also found that zbmp-2 was induced cell autonomously within the transplanted cells in the host ectoderm, suggesting that BMP cannot influence even the neighboring cells. This result is consistent with the observation that there is no gap between the expression domains of zbmp-2 and otx-2. Taken together, we propose that, in ectodermal patterning, BMP exerts a direct and cell-autonomous effect to fate uncommitted ectodermal cells to become epidermis.

Endogenous patterns of TGFbeta superfamily signaling during early Xenopus development

Development ◽  
2000 ◽  
Vol 127 (13) ◽  
pp. 2917-2931 ◽  
Author(s):  
S. Faure ◽  
M.A. Lee ◽  
T. Keller ◽  
P. ten Dijke ◽  
M. Whitman
Keyword(s):  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Ectopic Expression ◽  
Xenopus Embryo ◽  
Bmp Signaling ◽  
Type I ◽  
Embryonic Cells ◽  
Xenopus Development ◽  
Zygotic Transcription ◽  
Carboxy Terminal

Transforming growth factor beta (TGFbeta) superfamily signaling has been implicated in patterning of the early Xenopus embryo. Upon ligand stimulation, TGFbeta receptors phosphorylate Smad proteins at carboxy-terminal SS(V/M)S consensus motifs. Smads 1/5/8, activated by bone morphogenetic protein (BMP) signaling, induce ventral mesoderm whereas Smad2, activated by activin-like ligands, induces dorsal mesoderm. Although ectopic expression studies are consistent with roles for TGFbeta signals in early Xenopus embryogenesis, when and where BMP and activin-like signaling pathways are active endogenously has not been directly examined. In this study, we investigate the temporal and spatial activation of TGFbeta superfamily signaling in early Xenopus development by using antibodies specific for the type I receptor-phosphorylated forms of Smad1/5/8 and Smad2. We find that Smad1/5/8 and two distinct isoforms of Smad2, full-length Smad2 and Smad2(delta)exon3, are phosphorylated in early embryos. Both Smad1/5/8 and Smad2/Smad2(delta)exon3 are activated after, but not before, the mid-blastula transition (MBT). Endogenous activation of Smad2/Smad2(delta)exon3 requires zygotic transcription, while Smad1/5/8 activation at MBT appears to involve transcription-independent regulation. We also find that the competence of embryonic cells to respond to TGF(delta) superfamily ligands is temporally regulated and may be a determinant of early patterning. Levels of phospho-Smad1/5/8 and of phospho-Smad2/Smad2(delta)exon3 are asymmetrically distributed across both the animal-vegetal and dorsoventral axes. The timing of the development of these asymmetries differs for phospho-Smad1/5/8 and for phospho-Smad2/Smad2(delta)exon3, and the spatial distribution of phosphorylation of each Smad changes dramatically as gastrulation begins. We discuss the implications of our results for endogenous functions of BMP and activin-like signals as candidate morphogens regulating primary germ layer formation and dorsoventral patterning of the early Xenopus embryo.

dally, a Drosophila glypican, controls cellular responses to the TGF-beta-related morphogen, Dpp

Development ◽  
1997 ◽  
Vol 124 (20) ◽  
pp. 4113-4120 ◽  
Author(s):  
S.M. Jackson ◽  
H. Nakato ◽  
M. Sugiura ◽  
A. Jannuzi ◽  
R. Oakes ◽  
...  
Keyword(s):  
Growth Factor ◽  
Cell Surface ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Ectopic Expression ◽  
Cellular Responses ◽  
Growth Factor Signaling ◽  
Tgf Beta ◽  
Morphogenetic Protein

Decapentaplegic (Dpp) is a Drosophila member of the Transforming Growth Factor-beta (TGF-beta)/Bone Morphogenetic Protein (BMP) superfamily of growth factors. Dpp serves as a classical morphogen, where concentration gradients of this secreted factor control patterning over many cell dimensions. Regulating the level of Dpp signaling is therefore critical to its function during development. One type of molecule proposed to modulate growth factor signaling at the cell surface are integral membrane proteoglycans. We show here that division abnormally delayed (dally), a Drosophila member of the glypican family of integral membrane proteoglycans is required for normal Dpp signaling during development, affecting cellular responses to this morphogen. Ectopic expression of dally+ can alter the patterning activity of Dpp, suggesting a role for dally+ in modulating Dpp signaling strength. These findings support a role for members of the glypican family in controlling TGF-beta/BMP activity in vivo by affecting signaling at the cell surface.

scholarly journals Lycium barbarum Polysaccharide Suppresses Expression of Fibrotic Proteins in Primary Human Corneal Fibroblasts

2020 ◽  
Vol 9 (11) ◽  
pp. 3572
Author(s):  
Sum Sum Kwok ◽  
Francisca Siu-Yin Wong ◽  
Kendrick Co Shih ◽  
Yau-Kei Chan ◽  
Yashan Bu ◽  
...  
Keyword(s):  
Cell Viability ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Underlying Mechanism ◽  
Collagen Type I ◽  
In Vivo Studies ◽  
Type I ◽  
Lycium Barbarum ◽  
Stromal Fibroblasts

(1) Objective: To study the anti-fibrotic effects of Lycium barbarum polysaccharides (LBP) on corneal stromal fibroblasts and assess LBP’s effect on cell viability. (2) Methods: Primary human corneal keratocytes of passage 3 to 6 were used for all experiments. Cells are pretreated with LBP solution for 24 h and then transforming growth factor beta 1 (TGFβ1) for 48 h and collected for experiments. Fibrotic protein analysis was performed using immunofluorescence and Western blot. The effect of LBP on cell viability was assessed using the MTS assay. (3) Results: LBP significantly reduced the expression of fibrotic proteins, including α-SMA and extracellular matrix proteins (collagen type I and III). LBP significantly decreased the viability of myofibroblasts but not the fibroblasts. Conclusions: In this study, LBP was effective in the prevention of fibrosis gene expression. Further studies to assess the underlying mechanism and pharmacological properties will facilitate the formation of a topical LBP solution for in vivo studies.

scholarly journals Disruption of transforming growth factor beta signaling by a mutation that prevents transphosphorylation within the receptor complex.

1995 ◽  
Vol 15 (3) ◽  
pp. 1573-1581 ◽  
Author(s):  
J Cárcamo ◽  
A Zentella ◽  
J Massagué
Keyword(s):  
Growth Factor ◽  
Ligand Binding ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Signal Propagation ◽  
Tgf Beta ◽  
Wild Type ◽  
Growth Factor Beta ◽  
Signaling Activity

T beta R-II (transforming growth factor beta [TGF-beta] type II receptor) is a transmembrane serine/threonine kinase that acts as the primary TGF-beta receptor. Ligand binding to T beta R-II leads to the recruitment and phosphorylation of T beta R-I, a distantly related transmembrane kinase that acts as a downstream signaling component. T beta R-I phosphorylation by T beta R-II is shown here to be essential for signaling. A mutant T beta R-II that binds ligand but lacks signaling activity was identified. This mutant was identified by screening with a TGF-beta-inducible vector a series of mink lung epithelial cell clones that have normal TGF-beta binding activity but have lost antiproliferative and transcriptional responses to TGF-beta. When transiently cotransfected with T beta R-II, one of these cell lines, S-21, recovered TGF-beta responsiveness. cDNA cloning and sequencing of T beta R-II from S-21 cells revealed a point mutation that changes proline 525 to leucine in kinase subdomain XI. A recombinant receptor containing this mutation, T beta R-II(P525L), is similar to wild-type T beta R-II in its abilities to bind ligand, support ligand binding to T beta R-I, and form a complex with T beta R-I in vivo. T beta R-II(P525L) has autophosphorylating activity in vitro and in vivo; however, unlike the wild-type receptor, it fails to phosphorylate an associated T beta R-I. These results suggest that T beta R-II(P525L) is a catalytically active receptor that cannot recognize T beta R-I as a substrate. The close link between T beta R-I transphosphorylation and signaling activity argues that transphosphorylation is essential for signal propagation via T beta R-I.

scholarly journals Rap1 Regulates Hepatic Stellate Cell Migration through the Modulation of RhoA Activity in Response to Transforming Growth Factor-β1

2018 ◽  
Author(s):  
Mi-Young Moon ◽  
Hee-Jun Kim ◽  
Mo-Jong Kim ◽  
Sunho Uhm ◽  
Ji-Won Park ◽  
...  
Keyword(s):  
Cell Migration ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Stellate Cell ◽  
Active Form ◽  
Dominant Negative ◽  
Type I ◽  
Mrna Levels ◽  
Monocyte Migration

Although the migration of hepatic stellate cells (HSCs) is important for hepatic fibrosis, the regulation of HSC migration is poorly understood. Interestingly, transforming growth factor (TGF)-β1 induces monocyte migration to sites of injury or inflammation in the early phase but inhibits cell migration in the late phase. In this study, we investigated the role of RhoA signaling in TGF-β1-induced HSC migration. We found that TGF-β1 increased the protein and mRNA levels of α-SMA and collagen type I in HSC-T6 cells. The level of RhoA-GTP in TGF-β1-stimulated cells was significantly higher than that in control cells. Moreover, cofilin phosphorylation and F-actin formation was more strongly detected in TGF-β1-stimulated cells than in control cells. Additionally, TGF-β1 induced the activation of NF-κB and the expression of extracellular matrix proteins and several cytokines in HSC-T6 cells. The active form of Rap1 (Rap1 V12) suppressed RhoA-GTP levels, whereas the dominant negative form of Rap1 (Rap1 N17) augmented RhoA-GTP levels. Therefore, we confirmed that Rap1 regulates RhoA activation in TGF-β1-stimulated HSC-T6 cells. These findings suggest that TGF-β1 regulates Rap1, resulting in RhoA suppression, NF-κB activation and F-actin formation during the migration of HSCs.

scholarly journals Engineering a 3D hydrogel system to study optic nerve head astrocyte morphology and behavior in response to glaucomatous insult

2022 ◽  
Author(s):  
Ana N Strat ◽  
Alexander Kirschner ◽  
Hannah Yoo ◽  
Ayushi Singh ◽  
Tyler Bague ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Optic Nerve Head ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Uv Light ◽  
Collagen Type I ◽  
Data Sets ◽  
Type I ◽  
Extracellular Matrix Components

In glaucoma, astrocytes within the optic nerve head (ONH) rearrange their actin cytoskeleton, while becoming reactive and upregulating intermediate filament glial fibrillary acidic protein (GFAP). Increased transforming growth factor beta 2 (TGFβ2) levels have been implicated in glaucomatous ONH dysfunction. A key limitation of using conventional 2D culture to study ONH astrocyte behavior is the inability to faithfully replicate the in vivo ONH microenvironment. Here, we engineer a 3D ONH astrocyte hydrogel to better mimic in vivo mouse ONH astrocyte (MONHA) morphology, and test induction of MONHA reactivity using TGFβ2. Primary MONHAs were isolated from C57BL/6J mice and cell purity confirmed. To engineer 3D cell-laden hydrogels, MONHAs were mixed with photoactive extracellular matrix components (collagen type I, hyaluronic acid) and crosslinked for 5 minutes using a photoinitiator (0.025% riboflavin) and UV light (405-500 nm, 10.3 mW/cm2). MONHA-encapsulated hydrogels were cultured for 3 weeks, and then treated with TGFβ2 (2.5, 5.0 or 10 ng/ml) for 7 days to assess for reactivity. Following encapsulation, MONHA retained high cell viability in hydrogels and continued to proliferate over 4 weeks as determined by live/dead staining and MTS assays. Sholl analysis demonstrated that MONHAs within hydrogels developed increasing process complexity with longer process length over time. Cell processes connected with neighboring cells, coinciding with Connexin43 expression within astrocytic processes. Treatment with TGFβ2 induced reactivity in MONHA-encapsulated hydrogels as determined by altered F-actin cytoskeletal morphology, increased GFAP expression, and elevated fibronectin and collagen IV deposition. Our data sets the stage for future use of this 3D biomimetic ONHA-encapsulated hydrogel to investigate ONHA behavior in response to glaucomatous insult.

scholarly journals The Effects of Platelet-Derived Growth Factor Antagonism in Experimental Glomerulonephritis Are Independent of the Transforming Growth Factor–β System

2002 ◽  
Vol 13 (3) ◽  
pp. 658-667 ◽  
Author(s):  
Tammo Ostendorf ◽  
Uta Kunter ◽  
Claudia van Roeyen ◽  
Steven Dooley ◽  
Nebojsa Janjic ◽  
...  
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Matrix Protein ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Platelet Derived Growth Factor ◽  
Renal Diseases ◽  
Protein Accumulation ◽  
Type I

ABSTRACT. Platelet-derived growth factor B-chain (PDGF-B)– and transforming growth factor beta (TGF-β)–mediated accumulation of extracellular matrix proteins contributes to many progressive renal diseases. In vivo, specific antagonism of either PDGF-B or TGF-β in experimental mesangioproliferative glomerulonephritis resulted in an almost complete inhibition of matrix protein accumulation, which suggests an interaction between signaling pathways of these two growth factors. Because nothing is known on the nature of this possible interaction, PDGF-B was antagonized in the rat anti–Thy 1.1 model of glomerulonephritis by use of specific aptamers and its effects on the TGF-β system were investigated. Antagonism of PDGF-B led to a significant reduction of glomerular matrix accumulation compared with scrambled aptamer-treated nephritic controls. PDGF-B antagonism had no effect on the overexpression of glomerular TGF-β mRNA, TGF-β protein, or the expression of TGF-β receptor type I and II mRNA. By immunohistology, it was possible to detect overexpression of the cytoplasmic TGF-β signaling molecules Smad2 (agonistic) and Smad7 (antagonistic) in glomeruli of nephritic control rats which peaked on day 7 after disease induction, i.e., the peak of mesangial cell proliferation in this model. However, immunohistology and Western blot analysis again revealed no difference in the glomerular expression of both Smad proteins between PDGF-B antagonized and nonantagonized nephritic animals. In addition, no difference in the glomerular expression of phosphorylated Smad2 (P-Smad2) was detected between the differently treated nephritic groups. These observations suggest that the effects of PDGF-B antagonism are independent of TGF-β in mesangioproliferative glomerulonephritides.

scholarly journals Phosphocreatine Attenuates Isoproterenol-Induced Cardiac Fibrosis and Cardiomyocyte Apoptosis

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Hui Dai ◽  
Liang Chen ◽  
Dongyue Gao ◽  
Aihua Fei
Keyword(s):  
Transforming Growth Factor Beta ◽  
Cardiac Fibrosis ◽  
Collagen Type ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Cardiomyocyte Apoptosis ◽  
Tissue Inhibitor Of Metalloproteinase ◽  
Type I ◽  
Alpha Smooth Muscle Actin

The present study was designed to further explore the role and the underlying molecular mechanism of phosphocreatine (PCr) for cardiac fibrosis in vivo. Isoproterenol (ISO) was used to induce cardiac fibrosis in rats. PCr administration ameliorated fibrosis by reducing collagen accumulation and fibrosis-related signals, including transforming growth factor beta 1 (TGF-β1), alpha smooth muscle actin (α-SMA), collagen type I, and collagen type III. Mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways, including p38, extracellular signal regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p65, were highly activated by ISO and blocked by PCr. Moreover, PCr decreased ISO-induced matrix metalloproteinase-9 (MMP-9) and increased the tissue inhibitor of metalloproteinase-1 (TIMP-1) expression. Furthermore, PCr suppressed cardiomyocyte apoptosis induced by ISO, as shown by downregulated expression of the proapoptotic caspase-3, Bax, and upregulated expression of the antiapoptotic Bcl-2. Taken together, PCr can be an effective agent for preventing cardiac fibrosis and cardiomyocyte apoptosis.

scholarly journals Transforming Growth Factor-β1-Mediated Neuroprotection against Excitotoxic Injury in Vivo

2003 ◽  
Vol 23 (10) ◽  
pp. 1174-1182 ◽  
Author(s):  
Delphine Boche ◽  
Colm Cunningham ◽  
Jack Gauldie ◽  
V Hugh Perry
Keyword(s):  
Growth Factor ◽  
Bacterial Infection ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Active Form ◽  
Acute Injury ◽  
Cresyl Violet ◽  
Excitotoxic Lesion ◽  
Tgf Β1

Ischemic preconditioning is a phenomenon that describes how a sublethal ischemic insult can induce tolerance to subsequent ischemia. This phenomenon has been observed after focal or global ischemia in different animal models. However, the hypothesis that bacterial infection might lead to neuronal tolerance to injury has not been investigated. To mimic cerebral bacterial infection, we injected bacterial lipopolysaccharide (LPS) in the right dorsal hippocampus, followed 24 hours later by an excitotoxic lesion using kainic acid in the mouse model. Quantification of lesion size after cresyl violet counterstaining revealed that LPS pretreatment afforded neuroprotection to CA3 neurons against KA challenge. To investigate the events underlying this protection, we studied the cytokine profile induced after LPS injection. Interleukin (IL)-1β and transforming growth factor beta 1 (TGF-β1) were the main cytokines expressed at 24 hours after LPS injection. Because IL-1β has been described as deleterious in acute injury, we decided to investigate the function of TGF-β1. An adenovirus expressing a constitutively active form of TGF-β1 was injected intracerebrally 1 week before the induction of excitotoxic lesion, and neuronal protection was observed. To confirm the neuroprotective role of TGF-β1, the TGF-β1 adenovirus was replaced by recombinant human TGF-β1 protein and total neuroprotection was observed. Furthermore, the antibody-mediated blocking of TGF-β1 action prevented the protective effect of pretreatment with LPS. We have demonstrated in vivo that the cerebral tolerance phenomenon induced by LPS pretreatment is mediated by TGF-β1 cytokine.

scholarly journals Molecular forms of ruminant BMP15 and GDF9 and putative interactions with receptors

Reproduction ◽  
2017 ◽  
Vol 154 (4) ◽  
pp. 521-534 ◽  
Author(s):  
Derek A Heath ◽  
Janet L Pitman ◽  
Kenneth P McNatty
Keyword(s):  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Follicular Development ◽  
Molecular Forms ◽  
Published Data ◽  
Type I ◽  
Mutant Form ◽  
Surface Receptors

Bone morphogenetic factor 15 (BMP15) and growth differentiation factor 9 (GDF9) are oocyte-secreted factors with demonstrable effects on ovarian follicular development and ovulation rate. However, the molecular forms of BMP15 and GDF9 produced by oocytes remain unclear. The aims herein, using Western blotting (WB) procedures with specific monoclonal antibodies (mabs), were to identify the molecular forms of BMP15 and GDF9 synthesised and secreted by isolated ovine (o) and bovine (b) oocytes in vitro. The mabs were known to recognise the biological forms of BMP15 or GDF9 since they had previously been shown to inhibit their bioactivities in vitro and in vivo. Using recombinant variants of oBMP15 and oGDF9, including a cysteine mutant form of oBMP15 (S356C) and a human (h) BMP15:GDF9 heterodimer (cumulin), it was established that the mabs were able to identify monomeric, dimeric, promature and higher-molecular-weight forms of BMP15 and GDF9 and cumulin (GDF9 mab only). After using non-reducing, reducing and reducing + cross-linking conditions, the major oocyte-secreted forms of o and b BMP15 and GDF9 were the cleaved and uncleaved monomeric forms of the promature proteins. There was no evidence for dimeric or heterodimeric forms of either mature BMP15 or GDF9. From in silico modelling studies using transforming growth factor beta (TGFB), activin or BMP crystal templates, and both present and previously published data, a model is proposed to illustrate how the monomeric forms of BMP15 and GDF9 may interact with their type II and type I cell-surface receptors to initiate the synergistic actions of these growth factors.

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