Control of Bovine Adrenal Cortical Cell Proliferation by Fibroblast Growth Factor. Lack of Effect of Epidermal Growth Factor

Gospodarowicz, Denis; Ill, Charles R.; Hornsby, Peter J.; Gill, Gordon N.

doi:10.1210/endo-100-4-1080

Cited by 196 publications

(48 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This hypothesis is strengthened by the fact that, after hypophysectomy, corticotropin is no longer able to stimulate total protein synthesis, whereas it can still stimulate protein E synthesis. However, one cannot exclude the possibility that corticotropin stimulation of total protein synthesis is indirect, as postulated for DNA synthesis by Gospodarowicz et al (1977), and mediated by unknown pituitary factors, whose production could be stimulated by corticotropin.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Corticotropin regulation of the synthesis of a specific rat adrenal cytosolic protein. Effects of hypophysectomy and actinomycin D

Dazord

Gallet

Cohen

et al. 1979

Biochemical Journal

View full text Add to dashboard Cite

The mechanism of corticotropin stimulation of the synthesis of a specific rat adrenal cytosolic protein was investigated. This protein (protein E) has a mol.wt. of approx. 30000. It is detected by polyacrylamide-gel electrophoresis of cytosol prepared from adrenal slices from rats treated with corticotropin in vivo and control rats, the slices being incubated with [3H]-and ['4C]-leucine respectively. In rats 1-15 days after hypophysectomy, corticotropin, like dibutyryl cyclic AMP, induces an increase in protein E similar to that induced in control rats, even though both compounds no longer stimulate total protein synthesis. Corticotropin stimulation of protein E synthesis is mediated by cyclic AMP but not by corticosterone, since aminoglutethimide, a steroidogenic inhibitor, does not affect corticotropin stimulation, and dexamethasone alone has no effect. Actinomycin D, when injected in vivo 1 h before or after corticotropin injection, prevents the effect of corticotropin on protein E synthesis, which is interpreted as evidence that mRNA synthesis is necessary for the stimulation of protein E synthesis. When injected more than 2h after corticotropin, actinomycin D does not prevent corticotropin stimulation of protein E synthesis, but completely blocks corticotropin stimulation of total protein synthesis. This is interpreted as meaning that, after stimulation of mRNA coding for protein E, corticotropin has no effect on the synthesis of protein E. On the other hand, corticotropin stimulation of protein E synthesis persists after hypophysectomy even though it no longer stimulates total protein synthesis. These data suggest that the factor(s) involved in the synthesis of protein E are more stable than those involved in total protein synthesis.Hormonal induction of specific proteins has been studied in great detail for model systems that are under steroid-hormone control (Katzenellenbogen & Gorski, 1972;Schimke et al., 1975; Feigelson etal., 1975). Less work has been done with polypeptide hormones acting via cyclic AMP. Janszen et al. (1977) have shown that, in rat interstitial cell, lutropin induces an increased synthesis of a protein with an apparent mol.wt. of 21000 (lutropin-induced protein). It was further shown that the stimulatory effect of lutropin on this protein was mediated by cyclic AMP through an increase in mRNA (Janszen et al., 1978), but there is no evidence that this protein is involved in lutropin stimulation of testosterone biosynthesis. As far as corticotropin is concerned, the involvement of a rapidly turning-over protein mediating the steroidogenic action of the hormone was postulated several years ago (Garren et al., 1971;Schulster et al., 1974), but the identity of such a protein is still unknown. We have shown (Dazord et al., 1978) that, besides a general tropic effect on Vol. 182 most adrenal proteins, corticotropin produces a marked stimulation of a specific adrenal cytosolic protein (protein E) with mol.wt. approx. 30000 and p15.5. From our kinetic results (lack of effect of corticotropi...

show abstract

Section: Discussionmentioning

confidence: 99%

“…It has been postulated (Gospodarowicz et al, 1977) that growth induced by corticotropin in vivo is indirectly mediated by growth factors or related peptides. Hypophysectomized rats were used in order to eliminate interaction of cortico-717…”

mentioning

confidence: 99%

Corticotropin regulation of the synthesis of a specific rat adrenal cytosolic protein. Effects of hypophysectomy and actinomycin D

Dazord

Gallet

Cohen

et al. 1979

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…Primary cultures of bovine adrenal cortex cells (25) and granulosa cells (26) were prepared as described. For cell growth measurement, cell monolayers from stock plates were dissociated by exposure (2-3 min, 24°C) to a solution containing 0.9% NaCl, 0.01 M sodium phosphate (pH 7.4), 0.05% trypsin, and 0.02% EDTA (STV solution, Difco).…”

mentioning

confidence: 99%

Total synthesis of insulin-like growth factor I (somatomedin C).

Li¹,

Yamashiro²,

Gospodarowicz³

et al. 1983

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Human insulin-like growth factor I (somatomedin C) with 70 amino acid residues and three disulfide bridges has been synthesized by the solid-phase method. The synthetic product behaves as a pure polypeptide in paper electrophoresis, isoelectric focusing, and high-performance liquid chromatography. Its elution behavior in Sephadex G-50, isoelectric point, amino acid composition, and growth-stimulating activity in bovine adrenal cortical cells or granulosa cells are comparable to those reported for the natural product. In radioimmunoassay, the synthetic product is indistinguishable from the natural hormone when either synthetic or natural product is used as the labeled ligand.Production of somatomedins (SMs) and insulin-like growth factors (IGFs) is known to be stimulated by growth hormone (somatotropin) in animals (1, 2) and human subjects (3, 4). SM-C (5) and IGFs (6) have been purified to homogeneity from human plasma. Complete amino acid sequences for IGF-I (7) and IGF-II (8) have been proposed, but only limited sequence data for SM-C are known (5). Various bioassay and radioimmunoassay (RIA) data indicate that IGF-I and SM-C are identical (5, 9, 10). IGF-I consists of 70 amino acid residues with three disulfide bridges, and its structure is homologous to that of proinsulin (7, 11). Fig. 1 presents the primary structure of IGF-I as proposed by Rinderknecht and Humbel (7). Because chemical synthesis of any known growth factor has not been reported, this communication describes the total synthesis of IGF-I (SM-C). MATERIALS AND METHODSProtected IGF-I Resin. 4-(Boc-alanyloxymethyl)-phenylacetamidomethyl-resin (1.60 g, 0.60 mmol) prepared as described (12) was placed in a Beckman model 990 peptide synthesizer and carried through procedures of solid-phase synthesis (13) consisting of (i) 15-min deprotection with 50% (vol/vol) trifluoroacetic acid/CH2Cl2, (ii) neutralization with 5% (vol/vol) diisopropylethylamine (DIEA)/CH2Cl2 (two times). Coupling was effected with preformed symmetrical anhydrides (1.8 mmol, 3 eq) of for 20 min in CH2Cl2 except for Boc-Met(O)-OH, Boc-Arg(Tos)-OH, and Boc-Gln-OH, for which 40-min coupling was allowed and sufficient N,N-dimethylformamide was employed to give concentrations of 20, 15, and 20%, respectively. Boc-Asn-OH was coupled with dicyclohexylcarbodiimide and 1-hydroxybenzotriazole (15). In all cases a second coupling stage was performed (20 min): (i) for residues 69 through 59 and all subsequent couplings in which dimethylformamide was used 1 eq of DIEA was added (16); (ii) for all other residues 1 eq of N-methylmorpholine and sufficient trifluoroethanol to give a concentration of 20% were added (16). The following side-chain blocking groups were used: Asp, cyclopentyl (17); Thr, Ser, and Glu, benzyl; Cys, 3,4-dimethylbenzyl (18); Met, sulfoxide (19); Tyr and Lys, 2-bromobenzyloxycarbonyl; Arg, tosyl. The yield of protected peptide resin was 7.92 g (weight gain was 87% of theory).IGF-I. Protected IGF-I resin (1.336 g, 0.101 mmol) was treated with 50% trifluoroacetic ac...

show abstract

“…Cell Preparation and Culture.The procedure used for bovine adrenal cell preparation and culture was essentially that described by Gospodarowicz et al (1). Bovine adrenal glands were obtained from freshly slaughtered steers and transported to the laboratory on ice.…”

Section: Methodsmentioning

confidence: 99%

“…This cell culture system has been described and characterized (1)(2)(3). These cells are responsive to ACTH, as shown by increased cortisol output during the first few days of culture (3,4).…”

mentioning

confidence: 99%

Evidence for a higher molecular weight precursor of cholesterol side-chain-cleavage cytochrome P-450 and induction of mitochondrial and cytosolic proteins by corticotropin in adult bovine adrenal cells.

DuBois¹,

Simpson²,

Tuckey³

et al. 1981

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Adult bovine adrenal cortical cells in monolayer culture were used to study the induction of cholesterol side-chaincleavage cytochrome P-450 by corticotropin (ACTH). In the presence of 1 I&M ACTH, there was a 4-fold increase in cortisol production by these cells over a 72-hr period and a corresponding increase in total cytochrome.P-450 content. The incorporation of [rS]methionine into a number of cellular proteins-was stimulated* by the presence of ACTH in the culture medium, whereas the ncorporation into other proteins was decreased. The Thus, it appears that the cytochrome P-450stc content is increased in bovine adrenal cortical cells exposed to ACTH.. Cytochrome P450o, synthesized in a cell-free translation system directed by RNA isolated from bovine adrenal cortical tissue or from cells, had a molecular weight of 54,500. Cytochrome P-450SC, isolated from bovine adrenal. mitochondria had a molecular weight of 49,000.Thus, cytochrome P-450,,, is synthesized as a larger precursor that must be processed by proteolytic cleavage before or upon insertion into the mitochondrion.The molecular events by which corticotropin (ACTH) stimulates cholesterol side-chain.cleavage by adrenal mitochondria are being examined by using cultures of adult bovine adrenal cortical (BAC) cells. This cell culture system has been described and characterized (1-3). These cells are responsive to ACTH, as shown by increased cortisol output during the first few days of culture (3, 4). The rate-limiting step in cortisol biosynthesis is the first step in the pathway of cholesterol metabolism to steroid hormones-i.e., cholesterol side-chain cleavage (5). This reaction is catalyzed by a form of cytochrome P-450 known as side-chain-cleavage cytochrome P-450 (P-450sj), which is located in the inner membrane of the mitochondrion (6-9). Two other mitochondrial proteins, adrenodoxin and adrenodoxin reductase, serve to transfer electrons from NADPH to P-450S and are therefore also required for the conversion of cholesterol to pregnenolone (10, 11).ACTH is known to effect both an acute and a long-term (chronic) stimulation of the cholesterol side-chain-cleavage reaction. Our study was designed to characterize the long-term stimulation of cholesterol side-chain cleavage by ACTH. We examined radiolabeling profiles of proteins in BAC cells maintained. in monolayer culture at various times after addition of ACTH to the culture medium and found a complex pattern of changes. Examination of radiolabeled proteins in mitochondria isolated from such cells suggests that the level of P-450," is increased by ACTH administration. By using an antibody directed toward bovine adrenal cytochrome P-450,, we show that P-450. is synthesized in vitro as a larger molecular weight precursor that must be processed before or on insertion into the inner mitochondrial membrane. MATERIALS AND METHODSCell Preparation and Culture.The procedure used for bovine adrenal cell preparation and culture was essentially that described by Gospodarowicz et al. (1). Bovine adrenal gla...

show abstract

Control of Bovine Adrenal Cortical Cell Proliferation by Fibroblast Growth Factor. Lack of Effect of Epidermal Growth Factor

Cited by 196 publications

References 0 publications

Corticotropin regulation of the synthesis of a specific rat adrenal cytosolic protein. Effects of hypophysectomy and actinomycin D

Corticotropin regulation of the synthesis of a specific rat adrenal cytosolic protein. Effects of hypophysectomy and actinomycin D

Total synthesis of insulin-like growth factor I (somatomedin C).

Evidence for a higher molecular weight precursor of cholesterol side-chain-cleavage cytochrome P-450 and induction of mitochondrial and cytosolic proteins by corticotropin in adult bovine adrenal cells.

Contact Info

Product

Resources

About