The interleukin-1 receptor in Raji human B-lymphoma cells. Molecular characterization and evidence for receptor-mediated activation of gene expression.
In a previous paper [Horuk, Huang, Covington & Newton (1987) J. Biol. Chem. 262, 16275-16278] we reported that there were fundamental differences in the biochemical properties of the interleukin-1 (IL-1) receptor between Raji and EL4 cell lines. In the present study we have investigated the basis for these differences. Kinetic studies measuring the on and off rates of IL-1 receptor binding revealed that the low-affinity IL-1-binding sites observed in Raji cells, compared with EL4 cells, result from a combination of a lower association rate and a higher dissociation rate in the Raji cells. The turnover of the Raji IL-1 receptor, measured by inhibiting protein synthesis with cycloheximide, was much faster than that of the EL4 IL-1 receptor, with a half-time of 2 h as against 5 h. Treatment of 125I-IL-1-labelled IL-1 receptors in Raji and EL4 cells with neuraminidase decreased their molecular mass by approx. 2-5 kDa as assessed by SDS/polyacrylamide-gel electrophoresis (PAGE). The covalently labelled IL-1 receptors in both cell types were sensitive to treatment with endoglycosidase F, which decreased their molecular mass on SDS/PAGE by 12-13 kDa. Incubation of Raji cells with maximally stimulating doses of IL-1 resulted in an increase in the nascent RNA levels of several genes, including the IL-2 receptor and the proto-oncogenes c-Ha-ras and c-myc.
Horuk
R
R
Medical Products Division, E.I. du Pont De Nemours & Co., Glenolden Laboratory, PA 19036.
McCubrey
J A
JA
D001402:B-Lymphocytes / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism*; D008223:Lymphoma / Q000235:genetics / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000502:physiology*; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000378:metabolism
D007375:Interleukin-1; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins