Document Detail


Mitogens regulate the production of insulin-like growth factor-binding protein by Swiss 3T3 cells.
MedLine Citation:
PMID:  1703479     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Quiescent Swiss 3T3 cells can be stimulated to reenter the cell cycle by various mitogens used in synergistic combinations with insulin-like growth factors (IGFs). The cells constitutively secrete an IGF-binding protein (IGFBP), which can modulate the interaction of IGFs with their receptors and could, therefore, alter cellular responsiveness to IGFs. We have now characterized the IGFBP secreted by Swiss 3T3 cells and tested whether its secretion is regulated by heterologous mitogens. Ligand blotting using [125I]IGF-I revealed a major IGFBP of 40,000 mol wt, and treatment of the cells with tunicamycin reduced the mol wt of this protein to about 32,000. mRNA from Swiss 3T3 cells hybridized to a 32P-labeled oligonucleotide (50-mer) complementary to rat IGFBP-3. Taken together, these results indicate that the principal IGFBP secreted by Swiss 3T3 cells is probably the N-glycosylated IGFBP-3. Production of this IGFBP by Swiss 3T3 cells was stimulated by 50-150% by the mitogens bombesin, vasopressin, platelet-derived growth factor, epidermal growth factor, and 12-O-tetradecanoylphorbol 13-acetate and also by IGF-I. The increased production of IGFBP was first detected after 4-6h of incubation and was then maintained for 48-72 h. Agents that elevate intracellular cAMP and the glucocorticoid dexamethasone reduced IGFBP output. In cells in which protein kinase-C had been down-modulated, the stimulation of IGFBP output by 12-O-tetradecanoylphorbol 13-acetate was abolished, but the stimulation induced by the other mitogens was not prevented. Thus, the production of IGFBP by Swiss 3T3 cells can be regulated by a number of different signalling pathways.
Authors:
A N Corps; K D Brown
Related Documents :
2505719 - Identification of aggregation substances of enterococcus faecalis cells after induction...
19036709 - Classification of cell subpopulations using multiple cellular parameters from high-cont...
2832739 - Temperature-sensitive transport of glycoproteins to the surface of a variant mouse lymp...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Endocrinology     Volume:  128     ISSN:  0013-7227     ISO Abbreviation:  Endocrinology     Publication Date:  1991 Feb 
Date Detail:
Created Date:  1991-03-04     Completed Date:  1991-03-04     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  0375040     Medline TA:  Endocrinology     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1057-64     Citation Subset:  AIM; IM    
Affiliation:
Department of Biochemistry, Institute of Animal Physiology and Genetics Research, Cambridge, United Kingdom.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Carrier Proteins / chemistry,  genetics,  metabolism*
Cell Line
Electrophoresis
Insulin-Like Growth Factor Binding Proteins
Ligands
Mitogens / pharmacology*
RNA / metabolism
Somatomedins / metabolism
Tunicamycin / pharmacology
Chemical
Reg. No./Substance:
0/Carrier Proteins; 0/Insulin-Like Growth Factor Binding Proteins; 0/Ligands; 0/Mitogens; 0/Somatomedins; 11089-65-9/Tunicamycin; 63231-63-0/RNA

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Ontogeny of pituitary regulation of growth in the developing rat: comparison of effects of hypophyse...
Next Document:  Retinoid modulation of insulin-like growth factor-binding proteins and inhibition of breast carcinom...