Localized synthesis of the Vg1 protein during early Xenopus development

Development ◽  
1989 ◽  
Vol 106 (4) ◽  
pp. 775-785 ◽  
Author(s):  
D. Tannahill ◽  
D.A. Melton
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Small Proportion ◽  
Stage Iv ◽  
Early Embryo ◽  
Mesoderm Induction ◽  
Gastrula Stage ◽  
Small Peptide ◽  
Amphibian Embryo ◽  
Maternal Mrna

The Xenopus Vg1 gene encodes a maternal mRNA that is localized to the vegetal hemisphere of both oocytes and embryos and encodes a protein related to the TGF-beta family of small secreted growth factors. We have raised antibodies to recombinant Vg1 protein and used them to show that Vg1 protein is first detected in stage IV oocytes and reaches maximal levels in stage VI oocytes and eggs. During embryogenesis, Vg1 protein is synthesized until the gastrula stage. The embryonically synthesized Vg1 protein is present only in vegetal cells of an early blastula. We find that Vg1 protein is glycosylated and associated with membranes in the early embryo. Our results also suggest that a small proportion of the full-length Vg1 protein is cleaved to give a small peptide of M(r) = approximately 17 × 10(3). These results support the proposal that the Vg1 protein is an endogenous growth-factor-like molecule involved in mesoderm induction within the amphibian embryo.

Relationship of systemic immune dysregulation in advanced tumors to vascular growth factor overproduction

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e22124-e22124
Author(s):  
M. S. Block ◽  
S. N. Markovic
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Plasma Levels ◽  
Stage Iv ◽  
Elevated Plasma ◽  
Vascular Growth ◽  
Systemic Immunosuppression ◽  
Tumor Bearing ◽  
Advanced Tumors ◽  
Stage Iv Melanoma

e22124 Background: Therapeutic anti-cancer vaccine strategies have been effective in a broad range of preclinical tumor models, but clinical trials of vaccines in metastatic cancer patients have failed to show clinical benefit. We have previously shown that patients with stage IV melanoma have systemic immunosuppression including elevated plasma levels of immunosuppressive cytokines and impaired DTH responses to recall antigens. Patients with stage IV melanoma also have elevated circulating levels of the vascular growth factors vascular endothelial growth factor A (VEGF A) and placental growth factor (PlGF). Based on these observations, we have hypothesized that vascular growth factors such as VEGF and PlGF mediate systemic immunosuppression. Methods: FVB mice with established ANV6 transplantable breast tumors were bled, and plasma samples were assayed for VEGF, PlGF, and interleukin (IL)-10. Splenocytes taken from tumor-bearing mice were stimulated via the T cell receptor (TCR), and interferon gamma (IFN) production was measured. Splenocytes from normal mice were stimulated in the presence or absence of VEGF; IFN production was measured. Results: Compared with age- and sex-matched controls, tumor-bearing mice had elevated plasma levels of VEGF, PlGF, and the immunosuppressive cytokine IL-10 (see table ). Furthermore, splenocytes from tumor-bearing mice produced less IFN upon TCR stimulation than did splenocytes from control mice. Finally, normal mouse splenocytes produced less IFN when stimulated in the presence of VEGF than in its absence (70.2 ± 37.2 vs. 260.0 ± 130.9 pg/ml). Conclusions: We have shown that mice with advanced tumors exhibit both elevated levels of vascular growth factors and systemic immune inhibition. We have also shown that VEGF leads to impairment of immune function in normal splenocytes. Taken together, these results suggest that excess vascular growth factors may mediate immunosuppression in animals with advanced tumors, which may in turn impair anti-tumor vaccine efficacy. [Table: see text] No significant financial relationships to disclose.

Basic fibroblast growth factor induces notochord formation and the expression of As-T, a Brachyury homolog, during ascidian embryogenesis

Development ◽  
1996 ◽  
Vol 122 (7) ◽  
pp. 2023-2031 ◽  
Author(s):  
Y. Nakatani ◽  
H. Yasuo ◽  
N. Satoh ◽  
H. Nishida
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Basic Fibroblast Growth Factor ◽  
Mesoderm Induction ◽  
Fibroblast Growth ◽  
Halocynthia Roretzi ◽  
Cell Stage ◽  
Inductive Interaction ◽  
Notochord Cells

The tadpole larva of an ascidian develops 40 notochord cells in the center of its tail. Most of the notochord cells originate from the A-line precursors, among which inductive interactions are required for the subsequent differentiation of notochord. The presumptive-endoderm blastomeres or presumptive-notochord blastomeres themselves are inducers of notochord formation. Notochord induction takes place during the 32-cell stage. In amphibia, mesoderm induction is thought to be mediated by several growth factors, for example, activins and basic fibroblast growth factor (bFGF). In the ascidian, Halocynthia roretzi, treatment with bFGF of presumptive-notochord blastomeres that had been isolated at the early 32-cell stage promoted the formation of notochord at a low concentration of bFGF (0.02 ng/ml), while activin failed to induce notochord differentiation. The effect of bFGF reached a maximum at the end of the 32-cell stage and rapidly faded at the beginning of the subsequent cleavage, the time for full induction of notochord being at least 20 minutes. The expression of As-T, a previously isolated ascidian homolog of the mouse Brachyury (T) gene, starts at the 64-cell stage and is detectable exclusively in the presumptive-notochord blastomeres. The present study showed that presumptive-notochord blastomeres, isolated at the early 32-cell stage, neither differentiated into notochord nor expressed the As-T gene. However, when the presumptive-notochord blastomeres were coisolated or recombined with inducer blastomeres, transcripts of As-T were detected. When presumptive-notochord blastomeres were treated with bFGF, the expression of the As-T gene was also detected. These results suggest that inductive interaction is required for the expression of the As-T gene and that the expression of the As-T gene is closely correlated with the determined state of the notochord-precursor cells.

Mesoderm induction by fibroblast growth factor in early Xenopus development

1990 ◽  
Vol 327 (1239) ◽  
pp. 75-84 ◽  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Marginal Zone ◽  
Mesoderm Induction ◽  
Fibroblast Growth ◽  
Heparin Binding ◽  
Cell Stage ◽  
Animal Pole

In early amphibian development the mesoderm is formed around the equator of the blastula in response to inductive signals from the endoderm. At the time of its formation the mesoderm consists of a large ‘ventral type’ zone and a small ‘organizer’ zone. A screen of candidate substances showed that a small group of heparin binding growth factors (HBGFs) were active as mesoderm inducing agents in vitro . The fibroblast growth factors (aFGF and bFGF) and embryonal carcinoma derived growth factor (ECDGF) all show similar potency and can produce ventral inductions at concentrations above about 100 pM. Single blastula ectoderm cells can be induced and will differentiate in a defined medium to form mesodermal tissues and all inner blastula cells are competent to respond to the factors. Inducing activity can be extracted from Xenopus blastulae and can be purified by heparin affinity chromatography. Antibody neutralization and Western blotting experiments identify this activity as bFGF. The amounts present are small but would be sufficient to evoke ventral inductions in vivo. It is not yet known whether the bFGF is localized to the endoderm, although it is known that inducing activity secreted by endodermal cells can be neutralized by heparin. The competence of ectoderm to respond to FGF rises from about the 128-cell-stage and falls again by the onset of gastrulation. This change is paralleled by a rise and fall of binding of 125I-labelled aFGF. Chemical cross-linking reveals that this binding is attributable to a receptor of molecular mass about 130 kilodaltons (kDa). The receptor is present both in the marginal zone, which responds to the signal in vivo, and in the animal pole region, which is not induced in vivo but which will respond to HBGFs in vitro . In intact embryos we believe that the ventral type mesoderm forms the somites, kidney and other intermediate structures as well as the blood islands of the ventral midline. These intermediate structures are induced as a function of distance from the organizer in a process called ‘dorsalization’. Lithium salts have a dorsalizing effect on whole embryos and also on explants from the ventral marginal zone, causing them to form large blocks of muscle. Lithium will also cause large muscle blocks to form when applied to ectoderm explants together with FGF. It is difficult to extend these results directly to mammalian embryos, but we have shown that the products of the murine int-2 gene and of the human k-fgf genes are active as mesoderm inducing factors.

scholarly journals GRP94 Is Essential for Mesoderm Induction and Muscle Development Because It Regulates Insulin-like Growth Factor Secretion

2007 ◽  
Vol 18 (10) ◽  
pp. 3764-3775 ◽  
Author(s):  
Sherry Wanderling ◽  
Birgitte B. Simen ◽  
Olga Ostrovsky ◽  
Noreen T. Ahmed ◽  
Shawn M. Vogen ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Muscle Development ◽  
Es Cells ◽  
Primitive Streak ◽  
Mesoderm Induction ◽  
Insulin Like Growth Factor ◽  
Mouse Development ◽  
Factor Ii ◽  
Insulin Like Growth Factors

Because only few of its client proteins are known, the physiological roles of the endoplasmic reticulum chaperone glucose-regulated protein 94 (GRP94) are poorly understood. Using targeted disruption of the murine GRP94 gene, we show that it has essential functions in embryonic development. grp94−/− embryos die on day 7 of gestation, fail to develop mesoderm, primitive streak, or proamniotic cavity. grp94−/− ES cells grow in culture and are capable of differentiation into cells representing all three germ layers. However, these cells do not differentiate into cardiac, smooth, or skeletal muscle. Differentiation cultures of mutant ES cells are deficient in secretion of insulin-like growth factor II and their defect can be complemented with exogenous insulin-like growth factors I or II. The data identify insulin-like growth factor II as one developmentally important protein whose production depends on the activity of GRP94. Keywords: chaperone/HSP90/Insulin-like growth factors/mouse development.

scholarly journals Growth Factors, and Cytokines; Understanding the Role of Tyrosine Phosphatase SHP2 in Gametogenesis and Early Embryo Development

Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1798
Author(s):  
Muhammad Idrees ◽  
Seon-Hwa Oh ◽  
Tahir Muhammad ◽  
Marwa El-Sheikh ◽  
Seok-Hwan Song ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Embryo Development ◽  
Tyrosine Phosphatase ◽  
Embryo Implantation ◽  
Early Embryo ◽  
Cellular Growth ◽  
Protein Signaling ◽  
Early Embryo Development ◽  
Multifunctional Protein

Growth factors and cytokines have vital roles in germ cell development, gamete maturation, and early embryo development. Cell surface receptors are present for growth factors and cytokines to integrate with and trigger protein signaling in the germ and embryo intracellular milieu. Src-homology-2-containing phosphotyrosine phosphatase (SHP2) is a ubiquitously expressed, multifunctional protein that plays a central role in the signaling pathways involved in growth factor receptors, cytokine receptors, integrins, and G protein-coupled receptors. Over recent decades, researchers have recapitulated the protein signaling networks that influence gamete progenitor specification as well as gamete differentiation and maturation. SHP2 plays an indispensable role in cellular growth, survival, proliferation, differentiation, and migration, as well as the basic events in gametogenesis and early embryo development. SHP2, a classic cytosolic protein and a key regulator of signal transduction, displays unconventional nuclear expression in the genital organs. Several observations provided shreds of evidence that this behavior is essential for fertility. The growth factor and cytokine-dependent roles of SHP2 and its nuclear/cytoplasmic presence during gamete maturation, early embryonic development and embryo implantation are fascinating and complex subjects. This review is intended to summarize the previous and recent knowledge about the SHP2 functions in gametogenesis and early embryo development.

Insulin and epidermal growth factor are growth factors for isolated porcine thyroid follicles

1985 ◽  
Vol 110 (1_Suppla) ◽  
pp. S74
Author(s):  
R. GÄRTNER ◽  
W. GREIL ◽  
R. DEMHARTER ◽  
K. HORN
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Epidermal Growth

scholarly journals Growth Factor Therapy for Parkinson’s Disease: Alternative Delivery Systems

2021 ◽  
pp. 1-7
Author(s):  
Sarah Jarrin ◽  
Abrar Hakami ◽  
Ben Newland ◽  
Eilís Dowd
Keyword(s):  
Parkinson’S Disease ◽  
Gene Therapy ◽  
Parkinson's Disease ◽  
Growth Factors ◽  
Growth Factor ◽  
Ex Vivo ◽  
Brain Regions ◽  
Delivery Systems ◽  
Alternative Delivery

Despite decades of research and billions in global investment, there remains no preventative or curative treatment for any neurodegenerative condition, including Parkinson’s disease (PD). Arguably, the most promising approach for neuroprotection and neurorestoration in PD is using growth factors which can promote the growth and survival of degenerating neurons. However, although neurotrophin therapy may seem like the ideal approach for neurodegenerative disease, the use of growth factors as drugs presents major challenges because of their protein structure which creates serious hurdles related to accessing the brain and specific targeting of affected brain regions. To address these challenges, several different delivery systems have been developed, and two major approaches—direct infusion of the growth factor protein into the target brain region and in vivo gene therapy—have progressed to clinical trials in patients with PD. In addition to these clinically evaluated approaches, a range of other delivery methods are in various degrees of development, each with their own unique potential. This review will give a short overview of some of these alternative delivery systems, with a focus on ex vivo gene therapy and biomaterial-aided protein and gene delivery, and will provide some perspectives on their potential for clinical development and translation.

scholarly journals Growth factors in the regulation of reparative response in the presence of peritoneal damage

2020 ◽  
Vol 5 (4) ◽  
Author(s):  
Irina A. Shurygina ◽  
Мichael G. Shurygin ◽  
Lubov V. Rodionova ◽  
Nataliya I. Ayushinova
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Extended Period ◽  
Tissue Growth ◽  
Tissue Response ◽  
Heparin Binding ◽  
Lower Quadrant ◽  
Male Wistar Rats ◽  
The Right ◽  
Endothelial Growth Factor

AbstractObjectivesTo study the expression of growth factors in the regulation of tissue repair after peritoneal damage tissue response to peritoneal damage.MethodsExperimental study in 35 male Wistar rats determining the evolution over time of the tissue response to aseptic peritoneal damage. A standardized bowel and peritoneal lesions were created in the right lower quadrant by laparotomy. Then, tissular expression of growth factors was evaluated by multiplex polymerase chain reaction at seven timepoints between 6 h and 30 days, postoperatively.ResultsTissular responses of granulocyte-stimulating factors (Csf2, Csf3), connective tissue growth factor (Ctgf), epidermal growth factors and receptor (Egf, Egfr), fibroblast growth factors (Fgf2, 7 and 10), heparin binding EGF-like growth factor (Hbegf), hepatocyte growth factor (Hgf), insulin-like growth factor-1 (Igf1), mitogenic transforming growth factors (Tgfa, Tgfb1, Tgfbr3), and vascular endothelial growth factor A (Vegfa) were biphasic with a first expression peak at day 3, followed by a more pronounced peak at day 14.ConclusionsWe observed a long-lasting, widespread response of tissular growth factors for at least two weeks after peritoneal damage. To be clinically effective, the prophylaxis of postoperative adhesions might be needed for an extended period of time.

scholarly journals Utilizing the ABC Transporter for Growth Factor Production by fleQ Deletion Mutant of Pseudomonas fluorescens

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 679
Author(s):  
Benedict-Uy Fabia ◽  
Joshua Bingwa ◽  
Jiyeon Park ◽  
Nguyen-Mihn Hieu ◽  
Jung-Hoon Ahn
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Pseudomonas Fluorescens ◽  
Abc Transporter ◽  
Transforming Growth Factor Beta ◽  
Deletion Mutant ◽  
Transforming Growth Factor ◽  
Gene Knockout ◽  
Type I ◽  
Double Deletion

Pseudomonas fluorescens, a gram-negative bacterium, has been proven to be a capable protein manufacturing factory (PMF). Utilizing its ATP-binding cassette (ABC) transporter, a type I secretion system, P. fluorescens has successfully produced recombinant proteins. However, besides the target proteins, P. fluorescens also secretes unnecessary background proteins that complicate protein purification and other downstream processes. One of the background proteins produced in large amounts is FliC, a flagellin protein. In this study, the master regulator of flagella gene expression, fleQ, was deleted from P. fluorescens Δtp, a lipase and protease double-deletion mutant, via targeted gene knockout. FleQ directs flagella synthesis, so the new strain, P. fluorescens ΔfleQ, does not produce flagella-related proteins. This not only simplifies purification but also makes P. fluorescens ΔfleQ an eco-friendly expression host because it will not survive outside a controlled environment. Six recombinant growth factors, namely, insulin-like growth factors I and II, beta-nerve growth factor, fibroblast growth factor 1, transforming growth factor beta, and tumor necrosis factor beta, prepared using our supercharging method, were successfully secreted by P. fluorescens ΔfleQ. Our findings demonstrate the potential of P. fluorescens ΔfleQ, combined with our supercharging process, as a PMF.

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