Mitogen-mediated protein phosphorylation in Werner's syndrome fibroblasts.

Lysophosphatidic acid prevents apoptosis in fibroblasts via G(i)-protein-mediated activation of mitogen-activated protein kinase.

Lysophosphatidic acid (LPA) is a naturally occurring phospholipid with multiple biological functions. In the present study, we demonstrate that, besides its mitogenic activity, LPA is a potent survival factor, preventing serum-deprivation-induced apoptosis in fibroblasts and other cell types. Both the proliferative effect and survival activity of LPA are sensitive to the action of pertussis tox...

Modulation of testicular receptor 4 activity by mitogen-activated protein kinase-mediated phosphorylation.

Testicular receptor 4 (TR4) is an orphan member of the nuclear receptor superfamily. Despite the lack of identified ligands, its functional role has been demonstrated both in animals and cell cultures. However, it remains unclear how the biological activity of TR4 is regulated without specific ligands. In this study, we showed that in the absence of specific ligands the activity of TR4 could be...

Mitogen- and stress-activated protein kinase 1 activity and histone h3 phosphorylation in oncogene-transformed mouse fibroblasts.

Activation of the Ras-Raf-mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase-ERK signal transduction pathway or the SAPK2/p38 pathway results in the activation of mitogen- and stress-activated protein kinase 1 (MSK1). This activation of MSK1 leads to a rapid phosphorylation of histone H3 at Ser(10). Previously, we had demonstrated that Ser(10) phosphorylated H3 was ele...

Protein Kinase and Apoptotic Features Phosphorylation of p38 Mitogen-Activated Respond to Collagenous C1q with Cutting Edge: Proliferating Fibroblasts

Mitogen Receptors in Chick Embryo Fibroblasts

Insulin, a mitogen for cultured chick embryo fibroblasts (Temin, H. M. (1968) Cancer 3,771-787), has been employed to characterize the effects of mitogen/cell membrane interactions as it relates to growth. The specific binding of ‘*“I-insulin to substratum-attached cells is timeand temperature dependent and is optimum at a pH of 7.0. Fetal calf and chicken sera, somatomedin “A/C mixed,” and des...