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.

In vitro modulation of endothelial fenestrae: opposing effects of retinoic acid and transforming growth factor beta

1988 ◽  
Vol 91 (2) ◽  
pp. 313-318
Author(s):  
T. Lombardi ◽  
R. Montesano ◽  
M.B. Furie ◽  
S.C. Silverstein ◽  
L. Orci
Keyword(s):  
Endothelial Cells ◽  
Retinoic Acid ◽  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Surface Density ◽  
Transforming Growth Factor ◽  
Control Cell ◽  
Tgf Beta ◽  
Growth Factor Beta

Cultured endothelial cells isolated from fenestrated capillaries express many properties characteristic of their in vivo differentiated phenotype, including the formation of a limited number of fenestrae. In this study, we have investigated whether physiological factors that control cell differentiation might regulate the surface density of fenestrae in capillary endothelial cells. We have found that treatment of the cultures with retinoic acid (10 microM) induces a more than threefold increase in the surface density of endothelial fenestrae, whereas transforming growth factor beta (TGF beta) (2 ng ml-1) causes a sevenfold decrease in the surface density of these structures. These results show that the expression of endothelial fenestrae is susceptible to bidirectional modulation by physiological signals, and suggest that retinoids and TGF beta may participate in the regulation of fenestral density of capillary endothelium in vivo.

scholarly journals Transforming growth factor beta 1 (TGF-beta 1) induced neutrophil recruitment to synovial tissues: implications for TGF-beta-driven synovial inflammation and hyperplasia.

1991 ◽  
Vol 173 (5) ◽  
pp. 1121-1132 ◽  
Author(s):  
R A Fava ◽  
N J Olsen ◽  
A E Postlethwaite ◽  
K N Broadley ◽  
J M Davidson ◽  
...  
Keyword(s):  
Growth Factor ◽  
Synovial Tissue ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Biologically Active ◽  
Tgf Beta ◽  
Histological Techniques ◽  
Growth Factor Beta

We have studied the consequences of introducing human recombinant transforming growth factor beta 1 (hrTGF-beta 1) into synovial tissue of the rat, to begin to better understand the significance of the fact that biologically active TGF-beta is found in human arthritic synovial effusions. Within 4-6 h after the intra-articular injection of 1 microgram of hrTGF-beta 1 into rat knee joints, extensive recruitment of polymorphonuclear leukocytes (PMNs) was observed. Cytochemistry and high resolution histological techniques were used to quantitate the influx of PMNs, which peaked 6 h post-injection. In a Boyden chamber assay, hrTGF-beta 1 at 1-10 fg/ml elicited a chemotactic response from PMNs greater in magnitude than that evoked by FMLP, establishing that TGF-beta 1 is an effective chemotactic agent for PMNs in vitro as well as in vivo. That PMNs may represent an important source of TGF-beta in inflammatory infiltrates was strongly suggested by a demonstration that stored TGF-beta 1 was secreted during phorbol myristate acetate-stimulated degranulation in vitro. Acid/ethanol extracts of human PMNs assayed by ELISA contained an average of 355 ng of TGF/beta 1 per 10(9) cells potentially available for secretion during degranulation of PMNs. [3H]Thymidine incorporation in vivo and autoradiography of tissue sections revealed that widespread cell proliferation was triggered by TGF-beta 1 injection. Synovial lining cells and cells located deep within the subsynovial connective tissue were identified as sources of at least some of the new cells that contribute to TGF-beta 1-induced hyperplasia. Our results demonstrate that TGF-beta is capable of exerting pathogenic effects on synovial tissue and that PMNs may represent a significant source of the TGF-beta present in synovial effusions.

Transforming growth factor beta increases cell surface binding and assembly of exogenous (plasma) fibronectin by normal human fibroblasts

1988 ◽  
Vol 8 (10) ◽  
pp. 4234-4242
Author(s):  
B L Allen-Hoffmann ◽  
C L Crankshaw ◽  
D F Mosher
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Cell Surface ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Human Fibroblasts ◽  
Tgf Beta ◽  
Surface Binding ◽  
Amino Terminal ◽  
Cell Surface Binding

Transforming growth factor beta (TGF-beta) enhances the cell surface binding of 125I-fibronectin by cultured human fibroblasts. The effect of TGF-beta on cell surface binding was maximal after 2 h of exposure to TFG-beta and did not require epidermal growth factor or protein synthesis. The enhancement was dose dependent and was found with the 125I-labeled 70-kilodalton amino-terminal fragment of fibronectin as well as with 125I-fibronectin. Treatment of cultures with TGF-beta for 6 h resulted in a threefold increase in the estimated number of fibronectin binding sites. The increase in number of binding sites was accompanied by an increased accumulation of labeled fibronectin in detergent-insoluble extracellular matrix. The effect of TGF-beta was biphasic; after 6 h of exposure, less labeled fibronectin bound to treated cultures than to control cultures. Exposure of cells to TGF-beta for greater than 6 h caused a two- to threefold increase in the accumulation of cellular fibronectin in culture medium as detected by a quantitative enzyme-linked immunosorbent assay. The second phase of the biphasic effect and the increase in soluble cellular fibronectin were blocked by cycloheximide. Immunofluorescence staining of fibroblast cultures with antifibronectin revealed that TGF-beta caused a striking increase in fibronectin fibrils. The 70-kilodalton amino-terminal fragment of fibronectin, which blocks incorporation of fibronectin into extracellular matrix, blocked anchorage-independent growth of NRK-49F cells in the presence of epidermal growth factor. Our results show that an increase in the binding and rate of assembly of exogenous fibronectin is an early event preceding the increase in expression of extracellular matrix proteins. Such an early increase in cell surface binding of exogenous fibronectin may be a mechanism whereby TGF-beta can modify extracellular matrix characteristics rapidly after tissue injury or during embryonic morphogenesis.

scholarly journals The types II and III transforming growth factor-beta receptors form homo-oligomers.

1994 ◽  
Vol 126 (1) ◽  
pp. 139-154 ◽  
Author(s):  
Y I Henis ◽  
A Moustakas ◽  
H Y Lin ◽  
H F Lodish
Keyword(s):  
Growth Factor ◽  
Cell Surface ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Type Ii ◽  
Tgf Beta ◽  
Double Labeling ◽  
Beta Receptors ◽  
Growth Factor Beta ◽  
In Cells

Affinity-labeling experiments have detected hetero-oligomers of the types I, II, and III transforming growth factor beta (TGF-beta) receptors which mediate intracellular signaling by TGF-beta, but the oligomeric state of the individual receptor types remains unknown. Here we use two types of experiments to show that a major portion of the receptor types II and III forms homo-oligomers both in the absence and presence of TGF-beta. Both experiments used COS-7 cells co-transfected with combinations of these receptors carrying different epitope tags at their extracellular termini. In immunoprecipitation experiments, radiolabeled TGF-beta was bound and cross-linked to cells co-expressing two differently tagged type II receptors. Sequential immunoprecipitations using anti-epitope monoclonal antibodies showed that type II TGF-beta receptors form homo-oligomers. In cells co-expressing epitope-tagged types II and III receptors, a low level of co-precipitation of the ligand-labeled receptors was observed, indicating that some hetero-oligomers of the types II and III receptors exist in the presence of ligand. Antibody-mediated cross-linking studies based on double-labeling immunofluorescence explored co-patching of the receptors at the cell surface on live cells. In cells co-expressing two differently tagged type II receptors or two differently tagged type III receptors, forcing one receptor into micropatches by IgG induced co-patching of the receptor carrying the other tag, labeled by noncross-linking monovalent Fab'. These studies showed that homo-oligomers of the types II and III receptors exist on the cell surface in the absence or presence of TGF-beta 1 or -beta 2. In cells co-expressing types II and III receptors, the amount of heterocomplexes at the cell surface was too low to be detected in the immunofluorescence co-patching experiments, confirming that hetero-oligomers of the types II and III receptors are minor and probably transient species.

scholarly journals Regulation of Trypanosoma cruzi infections in vitro and in vivo by transforming growth factor beta (TGF-beta).

1991 ◽  
Vol 174 (3) ◽  
pp. 539-545 ◽  
Author(s):  
J S Silva ◽  
D R Twardzik ◽  
S G Reed
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Tgf Beta ◽  
Ifn Gamma ◽  
Human Macrophages ◽  
Growth Factor Beta ◽  
Cruzi Infection

The effects of transforming growth factor beta (TGF-beta) on interferon gamma-mediated killing of the intracellular protozoan parasite Trypanosoma cruzi and on the course of T. cruzi infection in mice were investigated. Spleen cells from mice with acute T. cruzi infections were found to produce elevated levels of biologically active TGF-beta in vitro, and the possibility that TGF-beta may mediate certain aspects of T. cruzi infection was then addressed. When mouse peritoneal macrophages were treated with TGF-beta in vitro, the ability of IFN-gamma to activate intracellular inhibition of the parasite was blocked. This occurred whether cells were treated with TGF-beta either before or after IFN-gamma treatment. TGF-beta treatment also blocked the T. cruzi-inhibiting effects of IGN-gamma on human macrophages. Additionally, treatment of human macrophages with TGF-beta alone led to increased parasite replication in these cells. The effects of TGF-beta on T. cruzi infection in vivo were then investigated. Susceptible C57BL/6 mice developed higher parasitemias and died earlier when treated with TGF-beta during the course of infection. Resistant C57BL/6 x DBA/2 F1 mice treated with TGF-beta also had increased parasitemias, and 50% mortality, compared with no mortality in infected, saline-treated controls. A single dose of TGF-beta, given at the time of infection, was sufficient to significantly decrease resistance to infection in F1 mice and to exacerbate infection in susceptible C57BL/6 mice. Furthermore, a single injection of TGF-beta was sufficient to counter the in vivo protective effects of IFN-gamma. We conclude that TGF-beta, produced during acute T. cruzi infection in mice, is a potent inhibitor of the effects of macrophage activating cytokines in vivo and in vitro and may play a role in regulating infection.

The biological effects of XTC-MIF: quantitative comparison with Xenopus bFGF

Development ◽  
1990 ◽  
Vol 108 (1) ◽  
pp. 173-183 ◽  
Author(s):  
J.B. Green ◽  
G. Howes ◽  
K. Symes ◽  
J. Cooke ◽  
J.C. Smith
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Biological Effects ◽  
Tissue Type ◽  
Mesoderm Induction ◽  
Tgf Beta ◽  
Signal Molecule ◽  
Animal Pole

Mesoderm in Xenopus and other amphibian embryos is induced by signals from the vegetal hemisphere acting on equatorial or animal hemisphere cells. These signals are diffusible and two classes of candidate signal molecule have been identified: the fibroblast growth factor (FGF) and transforming growth factor beta (TGF-beta) types. In this paper, we compare the effects of cloned Xenopus basic FGF (XbFGF) and electophoretically homogeneous XTC-MIF (a TGF-beta-like factor obtained from a Xenopus cell line) on animal pole explants. We find that they have a similar minimum active concentration (0.1-0.2 ng ml-1) but that, nonetheless, XTC-MIF is at least 40 times more active in inducing muscle. In general, we find that the two factors cause inductions of significantly different characters in terms of tissue type, morphology, gene expression and timing. At low concentrations (0.1-1.0 ng ml-1) both factors induce the differentiation of ‘mesenchyme’ and ‘mesothelium’ as well as blood-like cells. These latter cells do not, however, react with an antibody to Xenopus globin. This raised the possibility that the identification of red blood cells in other studies on mesoderm induction might have been mistaken, but combinations of animal pole regions with ventral vegetal pole regions confirmed that genuine erythrocytes are formed. The identity of the blood-like cells formed in response to the inducing factors remains unknown. At higher concentrations XTC-MIF induces neural tissue, notochord, pronephros and substantial and often segmented muscle. By contrast, XbFGF only induces significant amounts of muscle above 24 ng ml-1 and even then this is much less than that induced by XTC-MIF. For both factors an exposure of less than 30 min is effective. Competence of animal pole cells to respond to XbFGF is completely lost by the beginning of gastrulation (stage 10) while competence to XTC-MIF is detectable until somewhat later (stage 11). Since animal pole tissue is known to be able to respond to the natural inducer at least until stage 10, and perhaps until stage 10.5, this suggests that bFGF cannot be the sole inducer of mesoderm in vivo. Taken together, these results are consistent with XTC-MIF being a dorsoanterior inducer and XbFGF a ventroposterior inducer, suggesting that body pattern is established by the interaction of two types of inducing signal. This model is discussed in view of the qualitative and quantitative differences between the factors.

scholarly journals Immunoregulatory role of transforming growth factor beta (TGF-beta) in development of killer cells: comparison of active and latent TGF-beta 1.

1990 ◽  
Vol 172 (6) ◽  
pp. 1777-1784 ◽  
Author(s):  
S C Wallick ◽  
I S Figari ◽  
R E Morris ◽  
A D Levinson ◽  
M A Palladino
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Recombinant Dna ◽  
Chinese Hamster ◽  
Tgf Beta ◽  
Recombinant Dna Technology ◽  
Growth Factor Beta

Using recombinant DNA technology, we have generated Chinese hamster ovary (CHO) cell lines that synthesize latent transforming growth factor beta 1 (TGF-beta 1) to study immune regulation by TGF-beta 1. In vitro, latent TGF-beta 1 synthesized by transfectants or added exogenously as a purified complex after activation inhibited CTL generation to a similar extent as seen with acid-activated recombinant human (rHu) TGF-beta 1. In vivo, serum from nu/nu mice bearing CHO/TGF-beta 1 tumors contained significant levels of latent TGF-beta 1 in addition to depressed natural killer (NK) activity in spleens which paralleled that seen in C3H/HeJ mice treated with acid-activated rHuTGF-beta 1. rHuTGF-beta 1 treatment of mice receiving heart allografts resulted in significant enhancement of organ graft survival. Because of possible regulated tissue-specific activation, administration of latent rather than active TGF-beta may provide a better route to deliver this powerful immunosuppressive agent in vivo.

scholarly journals Transforming growth factor beta increases cell surface binding and assembly of exogenous (plasma) fibronectin by normal human fibroblasts.

1988 ◽  
Vol 8 (10) ◽  
pp. 4234-4242 ◽  
Author(s):  
B L Allen-Hoffmann ◽  
C L Crankshaw ◽  
D F Mosher
Keyword(s):  
Extracellular Matrix ◽  
Growth Factor ◽  
Cell Surface ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Human Fibroblasts ◽  
Tgf Beta ◽  
Surface Binding ◽  
Amino Terminal ◽  
Cell Surface Binding

Transforming growth factor beta (TGF-beta) enhances the cell surface binding of 125I-fibronectin by cultured human fibroblasts. The effect of TGF-beta on cell surface binding was maximal after 2 h of exposure to TFG-beta and did not require epidermal growth factor or protein synthesis. The enhancement was dose dependent and was found with the 125I-labeled 70-kilodalton amino-terminal fragment of fibronectin as well as with 125I-fibronectin. Treatment of cultures with TGF-beta for 6 h resulted in a threefold increase in the estimated number of fibronectin binding sites. The increase in number of binding sites was accompanied by an increased accumulation of labeled fibronectin in detergent-insoluble extracellular matrix. The effect of TGF-beta was biphasic; after 6 h of exposure, less labeled fibronectin bound to treated cultures than to control cultures. Exposure of cells to TGF-beta for greater than 6 h caused a two- to threefold increase in the accumulation of cellular fibronectin in culture medium as detected by a quantitative enzyme-linked immunosorbent assay. The second phase of the biphasic effect and the increase in soluble cellular fibronectin were blocked by cycloheximide. Immunofluorescence staining of fibroblast cultures with antifibronectin revealed that TGF-beta caused a striking increase in fibronectin fibrils. The 70-kilodalton amino-terminal fragment of fibronectin, which blocks incorporation of fibronectin into extracellular matrix, blocked anchorage-independent growth of NRK-49F cells in the presence of epidermal growth factor. Our results show that an increase in the binding and rate of assembly of exogenous fibronectin is an early event preceding the increase in expression of extracellular matrix proteins. Such an early increase in cell surface binding of exogenous fibronectin may be a mechanism whereby TGF-beta can modify extracellular matrix characteristics rapidly after tissue injury or during embryonic morphogenesis.

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.

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