Fibroblasts cultured from normal human forearm or genital skin were exposed to dexamethasone (DM) 10-9-10-7M, deoxycorticosterone (DOC) 10-6, or vehicle for 4-16 h and [-35S]methionine-labelled proteins compared by two-dimensional gel electrophoresis. No effects on cell number or [-35S]methionine incorporation were seen with either steroid, nor any effects of DOC on patterns of protein synthesis. In contrast, after 4 h incubation DM consistently (24/24 gels) caused increased abundance of a protein spot designated κ (kappa; Mr ∼ 41000, pKi, ∼ 6.5). After 16 h steroid exposure, levels of protein κ remained elevated; abundance of a second protein spot ω (omega; Mr ∼ 42000, pK1 ∼5.4) was consistently (8/8 gels) lower than in control fibroblasts. We interpret these data as evidence for glucocorticoid-specific effects on human skin fibroblasts, and that (within the pK1 and molecular weight range studied) the observed changes in abundance of proteins κ and ω constitute the human fibroblast glucocorticoid domain.
- two-dimensional gel electrophoresis