Cell-matrix interactions induce tyrosine phosphorylation of MAP kinases ERK1 and ERK2 and PLCgamma-1 in two-dimensional and three-dimensional cultures of human fibroblasts.

Using immunoprecipitation and phosphotyrosine detection by Western blotting, intracellular signaling intermediates were analyzed in human primary dermal fibroblasts, either seeded as monolayers on collagen I coats (2D) or seeded within three-dimensional collagen I lattices (3D). Previous results demonstrated that integrin activation in these systems resulted in a cascade of protein tyrosine phosphorylation, including focal adhesion kinase (D. Roeckel and T.