Growth-condition-dependent regulation of insulin-like growth factor II mRNA stability

Insulin-like growth factor II (IGF-II) is synthesized in many tissues, but the main site of production is the liver. In this paper we show that IGF-II mRNA levels are dependent on the growth conditions of the cells. In Hep3B cells, serum deprivation leads to a marked increase in IGF-II mRNA levels. Serum stimulation of starved Hep3B cells induces a decrease in the amount of IGF-II mRNA, which is not caused by a change in promoter activity. IGF-II mRNAs are subject to endonucleolytic cleavage, a process that requires two widely separated elements in the 3´ untranslated region of the mRNA. Specific regions of these elements can form a stable stem structure which is involved in the formation of RNA–protein complexes. By employing electrophoretic mobility shift assays, two complexes have been identified in cytoplasmic extracts of Hep3B cells. The formation of these complexes is related to the growth conditions of the cells and is correlated with the regulation of IGF-II mRNA levels. Our data suggest that, depending on whether serum is present or absent, a transition from one complex to the other occurs. A decrease in the IGF-II mRNA level is also observed when IGF-I or IGF-II is added to serum-deprived Hep3B cells, possibly providing a feedback mechanism for IGF-II production. The serum-induced degradation of IGF-II mRNAs does not require de novo protein synthesis, and is abolished by rapamycin, an inhibitor of p70 S6 kinase.

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Identification of a key regulatory element for the basal activity of the human insulin-like growth factor II gene promoter P3

Biochemical Journal ◽

10.1042/bj3270689 ◽

1997 ◽

Vol 327 (3) ◽

pp. 689-697 ◽

Cited By ~ 2

Author(s):

E. G. Luc RIETVELD ◽

P. Elly HOLTHUIZEN ◽

S. John SUSSENBACH

Keyword(s):

Growth Factor ◽

Cell Lines ◽

Human Insulin ◽

Regulatory Element ◽

Insulin Like Growth Factor ◽

Mobility Shift ◽

Basal Activity ◽

Factor Ii ◽

Hep3b Cells ◽

Active Promoter

Transcription of the human insulin-like growth factor II (IGF-II) gene is under the control of four promoters (P1-P4) that are differentially active during growth and development. Promoter 3 (P3) is the most active promoter during fetal development as well as in most adult tissues. P3 is also the most active promoter in tumour tissues and cell lines expressing IGF-II. Transient transfections of HeLa and Hep3B cells with truncated promoter constructs revealed that the region between -289 and -183 relative to the transcription start site supports basal promoter activity in both cell lines. Footprint experiments showed that the region between positions -192 and -172 (P3-4) is the only element bound by nuclear proteins. P3-4 is bound by five proteins, of which three proteins (proteins 3, 4 and 5) bind specifically and are expressed at the same levels in HeLa and Hep3B cells. Electrophoretic mobility shift assays and differential footprint experiments revealed the presence of two protein-binding regions within the P3-4 element. Proteins 4 and 5 bind box A (-193 to -188), whereas box B (-183 to -172) is bound by protein 3. From transcription experiments in vitro it can be concluded that Box A is essential for P3 activity. Box A is part of a region 11 dG residues long and is protected by proteins 4 and 5 that bind a contiguous set of six dG residues. DNA-binding of proteins 4 and 5 to box A requires the presence of Zn2+ ions. Thus structural and functional analysis reveals that the P3-4 element is a key regulatory element of P3 that contains two separate binding sites for proteins essential for the basal activity of IGF-II P3.

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Stimulation of Tetrahydrobiopterin Synthesis by Basic Fibroblast Growth Factor in Vascular Endothelial Cells

Pteridines ◽

10.1515/pteridines.2003.14.1.9 ◽

2003 ◽

Vol 14 (1) ◽

pp. 9-12 ◽

Cited By ~ 2

Author(s):

Shunichi Shimizu ◽

Yoshiyuki Miyasaka ◽

Shinichiro Yamamoto ◽

Masakazu Ishii ◽

Yuji Kiuchi

Keyword(s):

Endothelial Cells ◽

Growth Factor ◽

Fibroblast Growth Factor ◽

Basic Fibroblast Growth Factor ◽

De Novo ◽

Mrna Level ◽

Mrna Levels ◽

Dependent Manner ◽

Fibroblast Growth ◽

Concentration Dependent Manner

Abstract The purpose of this study was to examine whether basic fibroblast growth factor (bFGF) stimulates tetrahydrobiopterin (BH4) synthesis in mouse brain microvascular endothelial cells. BH4 content was determined by oxidation under acidic conditions as biopterin and analysed with reversed-phase high Performance liquid chromatography. Measurement of the mRNA level of QTP-cyclohydrolase I (GTPCH), which is the rate-limiting enzyme of the de novo pathway of BH4 synthesis. The addition of bFGF to endothelial cells increased the BH4 content and GTPCH mRNA levels in an incubation period- and a concentration-dependent manner. 2,4-Diamino-6- hydroxypyrimidine, an inhibitor of GTPCH, strongly reduced the bFGF-induced increase in BH4 content. These findings suggest that bFGF stimulates BH4 synthesis via a de novo pathway with the induction of GTPCH.

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Insulin, insulin-like growth factor II, and nerve growth factor effects on tubulin mRNA levels and neurite formation.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.82.20.7126 ◽

1985 ◽

Vol 82 (20) ◽

pp. 7126-7130 ◽

Cited By ~ 105

Author(s):

J. F. Mill ◽

M. V. Chao ◽

D. N. Ishii

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Mrna Levels ◽

Insulin Like Growth Factor ◽

Nerve Growth ◽

Factor Ii ◽

Neurite Formation ◽

Tubulin Mrna

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Methionine improves the performance and breast muscle growth of broilers with lower hatching weight by altering the expression of genes associated with the insulin-like growth factor-I signalling pathway

British Journal Of Nutrition ◽

10.1017/s0007114513002419 ◽

2013 ◽

Vol 111 (2) ◽

pp. 201-206 ◽

Cited By ~ 20

Author(s):

Chao Wen ◽

Ping Wu ◽

Yueping Chen ◽

Tian Wang ◽

Yanmin Zhou

Keyword(s):

Growth Factor ◽

Mrna Level ◽

Muscle Growth ◽

Breast Muscle ◽

Broiler Chicks ◽

Mrna Levels ◽

Insulin Like Growth Factor ◽

Factor I ◽

Igf I ◽

Growth Factor I

The present study aimed to investigate the responses of broilers with different hatching weights (HW) to dietary methionine (Met). A total of 192 1-d-old Arbor Acres broiler chicks with different HW (heavy: 48·3 (sem 0·1) g and light: 41·7 (sem 0·1) g) were allocated to a 2 (HW) × 2 (Met) factorial arrangement with six replicates of eight chicks. Control starter (1–21 d) and finisher (22–42 d) diets contained 0·50 and 0·43 % Met, respectively. Corresponding values for a high-Met treatment were 0·60 and 0·53 %. Light chicks had poorer (P< 0·05) growth performance and breast muscle weight and lower (P< 0·05) insulin-like growth factor-I (IGF-I) concentration and mRNA level in breast muscle than heavy chicks when both were fed the control diets. High-Met diets improved performance and promoted breast muscle growth and IGF-I concentration in light chicks (P< 0·05). Increased IGF-I and target of rapamycin (TOR) mRNA levels as well as decreased eIF4E-binding protein 1 (4EBP1), atrogin-1 and forkhead box O 4 (FOXO4) mRNA levels were induced by high-Met diets in light chicks (P< 0·05). In conclusion, the Met requirement of broilers might depend on their HW and Met levels used in the control diets in the present study were adequate for heavy chicks but inadequate for light chicks, resulting in poorer performance and breast muscle growth, which were improved by increasing dietary Met supply presumably through alterations in IGF-I synthesis and gene expression of the TOR/4EBP1 and FOXO4/atrogin-1 pathway.

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Amino acid limitation negatively regulates insulin-like growth factor-II mRNA levels and E-domain peptide secretion at a post-transcriptional step in BRL-3A rat liver cells.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)81373-x ◽

1988 ◽

Vol 263 (34) ◽

pp. 18404-18410

Author(s):

D S Straus ◽

C D Takemoto

Keyword(s):

Amino Acid ◽

Growth Factor ◽

Rat Liver ◽

Liver Cells ◽

Mrna Levels ◽

Insulin Like Growth Factor ◽

Factor Ii ◽

Rat Liver Cells ◽

Domain Peptide ◽

Peptide Secretion

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H19sense and antisense transgenes modify insulin-like growth factor-II mRNA levels

European Journal of Biochemistry ◽

10.1046/j.1432-1327.2000.01438.x ◽

2000 ◽

Vol 267 (13) ◽

pp. 4020-4027 ◽

Cited By ~ 35

Author(s):

Françoise Wilkin ◽

Jean Paquette ◽

Elisabeth Ledru ◽

Catherine Mamelin ◽

Michael Pollak ◽

...

Keyword(s):

Growth Factor ◽

Mrna Levels ◽

Insulin Like Growth Factor ◽

Factor Ii

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Glucocorticoids increase insulin-like growth factor-II mRNA accumulation in cultured human phaeochromocytoma cells

Journal of Endocrinology ◽

10.1677/joe.0.1420029 ◽

1994 ◽

Vol 142 (1) ◽

pp. 29-35 ◽

Cited By ~ 4

Author(s):

J Liu ◽

A I Kahri ◽

P Heikkilä ◽

W F Blum ◽

R Voutilainen

Keyword(s):

Gene Expression ◽

Growth Factor ◽

Protein Kinase ◽

Primary Cultures ◽

Cdna Probe ◽

Mrna Levels ◽

Insulin Like Growth Factor ◽

Mrna Accumulation ◽

Cytoplasmic Rna ◽

Factor Ii

Abstract Human phaeochromocytomas abundantly express insulin-like growth factor-II (IGF-II), but its regulation and biological role in these neoplasms is not known at present. To clarify the regulation of IGF-II gene expression in phaeochromocytomas, we studied the effects of glucocorticoids, nerve growth factor (NGF), and protein kinase A and C regulators in primary cultures of human phaeochromocytoma cells. Cytoplasmic RNA was extracted and analysed by Northern and dot blotting with a 32P-labelled cDNA probe for IGF-II. Dexamethasone treatment (500 ng/ml) for 3 and 7 days resulted in a 260% and 515% increase in the accumulation of IGF-II mRNA respectively. The stimulatory effect of dexamethasone was time-and dose-dependent. The increases in the 6·0 and 2·2 kb species of IGF-II mRNAs were the most apparent. Cortisol (1 μg/ml) increased the amount of IGF-II mRNA by threefold compared with the control. NGF (200 ng/ml), dibutyryl cyclic AMP (1 mm) and 12-O-tetradecanoyl phorbol-13-acetate (a protein kinase C activator; 100 ng/ml) had no significant effect on IGF-II mRNA levels. These data suggest that IGF-II gene expression in human phaeochromocytomas may be regulated by microenvironmental glucocorticoids. Journal of Endocrinology (1994) 142, 29–35

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A Functional Sp1 Binding Site Is Essential for the Activity of the Adult Liver-Specific Human Insulin-Like Growth Factor II Promoter

Molecular Endocrinology ◽

10.1210/mend.11.2.9888 ◽

1997 ◽

Vol 11 (2) ◽

pp. 237-250 ◽

Cited By ~ 9

Author(s):

Richard J. T. Rodenburg ◽

P. Elly Holthuizen ◽

John S. Sussenbach

Keyword(s):

Growth Factor ◽

Binding Site ◽

Insulin Like Growth Factor ◽

Start Site ◽

Adult Liver ◽

Transcription Start ◽

Mobility Shift ◽

Enhancer Binding Protein ◽

Factor Ii ◽

Electrophoretic Mobility Shift Assays

Abstract The human gene encoding insulin-like growth factor II contains four promoters (P1–P4) that are differentially activated in various tissues during development. Expression of insulin-like growth factor II in adult liver tissue is directed by P1, which is activated by liver-enriched members of the CCAAT/enhancer binding protein family of transcription factors. In the present report we show that the region around −48 relative to the transcription start site contains a high affinity Sp1 binding site. This was demonstrated by electrophoretic mobility shift assays using nuclear extracts from Hep3B hepatoma cells and with specific antibodies directed against Sp1. Competition electrophoretic mobility shift assays revealed that the Sp1 binding site of P1 and a consensus Sp1 binding site bind Sp1 with comparable efficiencies. Mutation of the Sp1 binding site results in an 85% decrease in P1 promoter activity in transient transfection assays using two different cell lines, COS-7 and Hep3B. Investigation of P1 mutants in which the spacing of the Sp1 binding site and the transcription start site was increased showed that the role of the Sp1 binding site in regulation of P1 is position dependent. Interestingly, the Sp1-responsive element cannot be exchanged by a functional TATA box. Activation of P1 by transactivators CCAAT/enhancer binding protein-β and hepatocyte nuclear factor-3β is strongly impaired after mutation of the Sp1 binding site. These results demonstrate that the specific presence of a binding site for the ubiquitously expressed transcription factor Sp1 is of eminent importance for efficient activation of P1 by liver-enriched transactivators.

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