ISSN:
1432-0827
Keywords:
Epidermal growth factor
;
Transcription factor
;
Osteoblasts
;
Protein kinase C
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
,
Physics
Notes:
Abstract The nuclear signaling events activated when epidermal growth factor (EGF) interacts with osteoblasts to produce effects on growth and differentiation are not clearly understood, and may include induction of immediate early genes such as Egr-1, a zinc finger transcription factor. In the present study, Northern analyses were performed to define the effects of EGF on the expression of Egr-1 mRNA in MC3T3-E1 mouse osteoblastic cells. Following treatment of quiescent, subconfluent MC3T3-E1 cells with 0.1–100 ng/ml EGF for various periods, maximal induction of Egr-1 mRNA occurred when cells were treated for 30–60 minutes with 1–10 ng/ml EGF. Inhibition of protein kinase C activity by pretreatment with 1 μM chelerythrine chloride or by prolonged stimulation with 50 ng/ml tetradecanoyl phorbol acetate (TPA) partially diminished the induction of Egr-1 by EGF. . Using an immunohistochemical approach, 10 ng/ml EGF was this induction was localized to the nucleus. These observations indicate that EGF induces Egr-1 mRNA and protein via protein kinase C and other signaling pathways, and that Egr-1 may be part of the regulatory network mediating the actions of EGF on growth and differentiation of osteoblasts.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00301949
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