Abstract
The binding of epidermal growth factor (EGF) and of glucagon to their receptors has been examined in single-cell suspensions obtained from livers and other organs of newborn mice homozygous for a perinatally lethal deletion that includes the albino (c) locus on chromosome 7. Competition experiments with 125I-labeled and nonradioactive EGF and Scatchard analysis of equilibrium binding data showed that hepatocytes from deletion homozygotes had only approximately equal to 20% of the number of specific EGF receptors present in cells from normal littermates. In contrast, EGF binding to single-cell suspensions from organs other than the liver was normal in deletion homozygotes. Similar results were obtained in competitive displacement experiments with 125I-labeled and nonradioactive glucagon: hepatocytes from deletion mutants showed only approximately equal to 30% of the specific glucagon binding sites found in cells from normal littermates. As in the case of EGF, the decreased binding was due to decreased numbers of glucagon receptors per cell rather than alterations in receptor affinity, and glucagon binding to single-cell suspensions from organs other than the liver was normal in the deletion mutants. The reductions in numbers of EGF and glucagon receptors are liver-cell specific as are the previously described ultrastructural and biochemical abnormalities in these mutants. The significance of cell membrane integrity and hormone-receptor interactions in the control of normal liver cell differentiation is discussed.
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Selected References
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- Adamson E. D., Deller M. J., Warshaw J. B. Functional EGF receptors are present on mouse embryo tissues. Nature. 1981 Jun 25;291(5817):656–659. doi: 10.1038/291656a0. [DOI] [PubMed] [Google Scholar]
- Amsterdam A., Jamieson J. D. Structural and functional characterization of isolated pancreatic exocrine cells. Proc Natl Acad Sci U S A. 1972 Oct;69(10):3028–3032. doi: 10.1073/pnas.69.10.3028. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carpenter G., Cohen S. 125I-labeled human epidermal growth factor. Binding, internalization, and degradation in human fibroblasts. J Cell Biol. 1976 Oct;71(1):159–171. doi: 10.1083/jcb.71.1.159. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Carpenter G., Cohen S. Epidermal growth factor. Annu Rev Biochem. 1979;48:193–216. doi: 10.1146/annurev.bi.48.070179.001205. [DOI] [PubMed] [Google Scholar]
- Gluecksohn-Waelsch S. Genetic control of morphogenetic and biochemical differentiation: lethal albino deletions in the mouse. Cell. 1979 Feb;16(2):225–237. doi: 10.1016/0092-8674(79)90001-1. [DOI] [PubMed] [Google Scholar]
- Goldfeld A. E., Firestone G. L., Shaw P. A., Gluecksohn-Waelsch S. Recessive lethal deletion on mouse chromosome 7 affects glucocorticoid receptor binding activities. Proc Natl Acad Sci U S A. 1983 Mar;80(5):1431–1434. doi: 10.1073/pnas.80.5.1431. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goldfeld A. E., Rubin C. S., Siegel T. W., Shaw P. A., Schiffer S. G., Gluecksohn-Waelsch S. Genetic control of insulin receptors. Proc Natl Acad Sci U S A. 1981 Oct;78(10):6359–6361. doi: 10.1073/pnas.78.10.6359. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maxfield F. R., Schlessinger J., Shechter Y., Pastan I., Willingham M. C. Collection of insulin, EGF and alpha2-macroglobulin in the same patches on the surface of cultured fibroblasts and common internalization. Cell. 1978 Aug;14(4):805–810. doi: 10.1016/0092-8674(78)90336-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Trigg M. J., Gluecksohn-Waelsch S. Ultrastructural basis of biochemical effects in a series of lethal alleles in the mouse. Neonatal and developmental studies. J Cell Biol. 1973 Sep;58(3):549–563. doi: 10.1083/jcb.58.3.549. [DOI] [PMC free article] [PubMed] [Google Scholar]