Deletion of C-terminal 113 amino acids impairs processing and internalization of human insulin receptor: Comparison of receptors expressed in CHO and NIH-3T3 cells

We demonstrate that a member of the fos family, the fosB gene, gives rise to two transcripts by alternative splicing of exon 4, generating two proteins, FosB of 338 amino acids and a short form, FosB/SF, which contains the DNA binding and dimerization domains but not the 101 amino acids of the C terminus. FosB/SF activates an AP-1-chloramphenicol acetyltransferase construct in NIH 3T3 cells, as determined by transient and stable transfections, although more weakly than does FosB. In contrast to FosB, FosB/SF has lost its ability to repress the dyad symmetry element of the c-fos gene. FosB/SF when expressed in excess to FosB can downmodulate the activity of FosB. Constitutive expression of high levels of FosB/SF in NIH 3T3 cells has no significant inhibitory effect in the induction of cell proliferation or cell cycle progression, indicating that FosB/SF is not a negative regulator of cell growth. This conclusion is further confirmed by the observation that the majority of the Jun molecules are complexed with FosB/SF in the FosB/SF-overexpressing cells.

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Expression of a human insulin-like growth factor II cDNA in NIH-3T3 cells

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(90)91968-x ◽

1990 ◽

Vol 169 (3) ◽

pp. 832-839 ◽

Cited By ~ 6

Author(s):

Daniel M. Buergisser ◽

Birgit V. Roth ◽

Christine Luethi ◽

Hans Peter Gerber ◽

Annemarie Honegger ◽

...

Keyword(s):

Growth Factor ◽

Human Insulin ◽

Insulin Like Growth Factor ◽

3T3 Cells ◽

Factor Ii ◽

Nih 3T3 ◽

Nih 3T3 Cells

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Both products of the fosB gene, FosB and its short form, FosB/SF, are transcriptional activators in fibroblasts.

Molecular and Cellular Biology ◽

10.1128/mcb.11.11.5470 ◽

1991 ◽

Vol 11 (11) ◽

pp. 5470-5478 ◽

Cited By ~ 62

Author(s):

P Dobrazanski ◽

T Noguchi ◽

K Kovary ◽

C A Rizzo ◽

P S Lazo ◽

...

Keyword(s):

Amino Acids ◽

Cell Cycle Progression ◽

Short Form ◽

Constitutive Expression ◽

Inhibitory Effect ◽

Negative Regulator ◽

3T3 Cells ◽

C Terminus ◽

Nih 3T3 ◽

Nih 3T3 Cells

We demonstrate that a member of the fos family, the fosB gene, gives rise to two transcripts by alternative splicing of exon 4, generating two proteins, FosB of 338 amino acids and a short form, FosB/SF, which contains the DNA binding and dimerization domains but not the 101 amino acids of the C terminus. FosB/SF activates an AP-1-chloramphenicol acetyltransferase construct in NIH 3T3 cells, as determined by transient and stable transfections, although more weakly than does FosB. In contrast to FosB, FosB/SF has lost its ability to repress the dyad symmetry element of the c-fos gene. FosB/SF when expressed in excess to FosB can downmodulate the activity of FosB. Constitutive expression of high levels of FosB/SF in NIH 3T3 cells has no significant inhibitory effect in the induction of cell proliferation or cell cycle progression, indicating that FosB/SF is not a negative regulator of cell growth. This conclusion is further confirmed by the observation that the majority of the Jun molecules are complexed with FosB/SF in the FosB/SF-overexpressing cells.

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Structure and receptor-binding activity of insulin from a holostean fish, the bowfin (Amia calva)

Biochemical Journal ◽

10.1042/bj2760261 ◽

1991 ◽

Vol 276 (1) ◽

pp. 261-264 ◽

Cited By ~ 22

Author(s):

J M Conlon ◽

J H Youson ◽

J Whittaker

Keyword(s):

Biological Activity ◽

Human Insulin ◽

Binding Activity ◽

Vertebrate Species ◽

3T3 Cells ◽

Receptor Binding Activity ◽

Human Insulin Receptor ◽

A Chain ◽

Amia Calva ◽

Nih 3T3

The holostean fishes are the extant representatives of the primitive ray-finned fishes from which the present-day teleosts may have evolved. The primary structure of insulin from a holostean fish, the bowfin (Amia calva), was established as: A-chain: Gly-Ile-Val-Glu-Gln-Cys-Cys-Leu-Lys-Pro-Cys-Thr-Ile-Tyr-Glu-Met-Glu- Lys-Tyr-Cys-Asn B-chain: Ala-Ala-Ser-Gln-His-Leu-Cys-Gly-Ser-His-Leu-Val-Glu-Ala-Leu-Phe-Leu- Val-Cys-Gly-Glu-Ser-Gly-Phe-Phe-Tyr-Asn-Pro-Asn-Lys-Ser This amino acid sequence contains several substitutions (methionine at A16, phenylalanine at B16 and serine at B22) at sites that have been strongly conserved in other vertebrate species and that may be expected to influence biological activity. Consistent with this prediction, bowfin insulin was approx. 14-fold less potent than pig insulin in inhibiting the binding of [125I-Tyr-A14](human insulin) to transfected mouse NIH 3T3 cells expressing the human insulin receptor.

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Volume regulation in NIH/3T3 cells not expressing P-glycoprotein. II. Chloride and amino acid fluxes

AJP Cell Physiology ◽

10.1152/ajpcell.1997.272.6.c1804 ◽

1997 ◽

Vol 272 (6) ◽

pp. C1804-C1809 ◽

Cited By ~ 78

Author(s):

J. Moran ◽

D. Miranda ◽

C. Pena-Segura ◽

H. Pasantes-Morales

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Regulatory Volume Decrease ◽

Disulfonic Acid ◽

Channel Blockers ◽

3T3 Cells ◽

P Glycoprotein ◽

Arachidonic Acids ◽

Nih 3T3 ◽

Nih 3T3 Cells

The osmolyte function of amino acids and Cl in native NIH/3T3 cells not expressing the P-glycoprotein was examined by investigating the free amino acid concentration and the swelling-activated efflux of [3H]taurine, as representative of amino acids, and of 125I, as a tracer for Cl. Taurine and 125I efflux was activated by 20 and 30% hyposmotic solutions. At 50% hyposmotic solutions, the osmolyte pool was essentially depleted. The Cl channel blockers 5-nitro-2-(3-phenylpropyl-amino)benzoic acid, 1,9-dideoxyforskolin, dipyridamole, and niflumic acid inhibited the release of the two osmolytes by 80-95%. 4,4'-Diisothiocyanostilbene-2,2'-disulfonic acid (400 microM) decreased the efflux of taurine 80% without affecting that of 125I. Linolenic and arachidonic acids (5-20 microM) showed a concentration-dependent inhibitory effect on taurine and 125I fluxes. Omission of Ca decreased osmolyte fluxes by 16%. Verapamil inhibited the osmolyte release only at 500 microM. Nimodipine at 25 and 50 microM decreased the release of [3H]taurine and 125I by approximately 60 and 80%, respectively, but this effect was independent of the presence of extracellular Ca. These results indicate that amino acids and Cl function as osmolytes during regulatory volume decrease in native NIH/ 3T3 cells.

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Volume regulation in NIH/3T3 cells not expressing P-glycoprotein. I. Regulatory volume decrease

AJP Cell Physiology ◽

10.1152/ajpcell.1997.272.6.c1798 ◽

1997 ◽

Vol 272 (6) ◽

pp. C1798-C1803 ◽

Cited By ~ 13

Author(s):

H. Pasantes-Morales ◽

R. Sanchez Olea ◽

D. Miranda ◽

J. Moran

Keyword(s):

Amino Acids ◽

Regulatory Volume Decrease ◽

K Channel ◽

Gamma Aminobutyric Acid ◽

3T3 Cells ◽

P Glycoprotein ◽

Volume Recovery ◽

Nih 3T3 ◽

Volume Decrease ◽

Nih 3T3 Cells

Exposure of NIH/3T3 fibroblasts not expressing P-glycoprotein to 50, 30, 20, and 10% hyposmotic solutions led to cell volume increases of 70, 32, 21, and 12%, respectively. After swelling, NIH/3T3 cells exhibited regulatory volume decrease (RVD), attaining complete volume recovery after 30 min except in 50% hyposmotic solution, in which volume recovery was 76%. RVD was accelerated by gramicidin and inhibited by the Cl channel blockers 5-nitro-2-(3-phenylpropylamino)-benzoic acid, 1,9-dideoxyforskolin, dipyridamole, and niflumic acid and by the K channel, blocker quinidine. RVD was reduced 15% by removal of extracellular Ca. The pathway opened by hypotonicity was highly permeable to K and Rb and only partly permeable to other cations. Most anions were able to permeate, with a permeability ranking of nitrate > benzoate = iodide > thiocyanate > chloride > > gluconate. The pathway was permeable to neutral amino acids, with a permeability ranking of glycine > alanine > glutamate > taurine > gamma-aminobutyric acid > glutamine. The pathway was not permeable to basic amino acids. These results show that, despite the absence of P-glycoprotein, NIH/3T3 cells exhibit RVD with properties similar to those expressed in most cell types.

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