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Induction and Analysis of Epithelial to Mesenchymal Transition
10:37

Induction and Analysis of Epithelial to Mesenchymal Transition

Published on: August 27, 2013

Biphasic effects of type beta transforming growth factor on epidermal growth factor receptors in NRK fibroblasts.

R K Assoian

    The Journal of Biological Chemistry
    |August 15, 1985
    PubMed

    Insights

    Transforming growth factor-beta (TGF-beta) alters epidermal growth factor (EGF) receptors in NRK cells, affecting cell growth. These changes in EGF receptor binding correlate with TGF-beta's dual impact on cell proliferation.

    Area of Science:

    • Cell Biology
    • Molecular Biology
    • Biochemistry

    Background:

    • Transforming growth factor-beta (TGF-beta) is a key regulator of cell growth and differentiation.
    • Epidermal growth factor (EGF) receptors play a crucial role in cell signaling and proliferation.
    • Understanding the interplay between TGF-beta and EGF signaling is vital for comprehending cell growth regulation.

    Purpose of the Study:

    • To investigate the effects of TGF-beta on the subpopulations of plasma membrane epidermal growth factor (EGF) receptors in NRK cells.
    • To elucidate the functional consequences of TGF-beta-induced alterations in EGF receptor binding on EGF-stimulated cell proliferation.

    Main Methods:

    • NRK cells were treated with TGF-beta.
    • Changes in EGF receptor affinity and number were assessed.
    • EGF-stimulated thymidine incorporation was measured to evaluate cell proliferation.

    Main Results:

    • TGF-beta treatment increased the number of low-affinity EGF receptors.
    • High-affinity EGF receptors showed a transient decrease in affinity followed by an increase in number.
    • Cycloheximide inhibited these TGF-beta-induced receptor alterations.
    • TGF-beta modulated EGF sensitivity, enhancing proliferation in the long term and inhibiting it transiently.

    Conclusions:

    • TGF-beta exerts a bifunctional effect on NRK cells by altering EGF receptor dynamics.
    • These biochemical changes in EGF receptor binding are consistent with TGF-beta's observed effects on cell growth.
    • The study highlights a complex regulatory mechanism involving TGF-beta and EGF signaling pathways.

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