The role of G protein-coupled receptors and their ligands in intestinal epithelial cell signaling and proliferation is poorly understood. Here, we demonstrate that arginine vasopressin (AVP) induces multiple intracellular signal transduction pathways in rat intestinal epithelial IEC-18 cells via a V(1A) receptor. Addition of AVP to these cells induces a rapid and transient increase in cytosolic...

Stimulation of rat pheochromocytoma PC12 cells with ionophore A23187, carbachol, or high K+ medium, agents which increase intracellular Ca2+, results in the phosphorylation and activation of tyrosine hydroxylase (Nose, P., Griffith, L. C., and Schulman, H. (1985) J. Cell Biol. 101, 1182-1190). We have identified three major protein kinases in PC12 cells and investigated their roles in the Ca2+-...

The rat neu oncogene product is a member of the epidermal growth factor (EGF) receptor subgroup of the superfamily of growth factor receptor tyrosine kinases. The oncogenic activation of the neu protein occurs by a point mutation within its transmembrane region which results in an increase in its tyrosine kinase activity. Using three different forms of neu expressed in insect cells via baculovi...

This review article outlines the current development of emerging treatment strategies for primary central nervous system lymphoma, a rare brain tumor with, thus far, limited therapeutic options. Small molecule targeted tyrosine kinase inhibitors, immunomodulatory agents, and immune checkpoint inhibitors will be discussed. The mechanisms action, results completed clinical studies, ongoing trials...

TFII-I is a transcription factor that shuttles between the cytoplasm and nucleus and is regulated by serine and tyrosine phosphorylation. Tyrosine phosphorylation of TFII-I can be regulated in a signal-dependent manner in various cell types. In B lymphocytes, Bruton's tyrosine kinase has been identified as a TFII-I tyrosine kinase. Here we report that JAK2 can phosphorylate and regulate TFII-I ...

Integrin-mediated cell adhesion causes activation of MAP kinases and increased tyrosine phosphorylation of focal adhesion kinase (FAK). Autophosphorylation of FAK leads to the binding of SH2-domain proteins including Src-family kinases and the Grb2-Sos complex. Since Grb2-Sos is a key regulator of the Ras signal transduction pathway, one plausible hypothesis has been that integrin-mediated tyro...

OBJECTIVE Glucose 6-phosphate dehydrogenase (G6PD) maintains cellular NADPH levels, which are essential for cellular functions, such as vascular endothelial growth factor (VEGF)-induced angiogenesis. The molecular mechanisms regulating G6PD in angiogenesis are not fully understood. Because tyrosine phosphorylation is a key regulatory pathway for VEGF-mediated endothelial cell (EC) responses, we...

Ligation of the interleukin-7 receptor (IL-7R) results in a rapid phosphorylation of tyrosine residues on multiple substrates. In addition, we have recently shown that the IL-7R mediates activation of phosphatidylinositol-3 (PI-3) kinase. Because PI-3 kinase activity can be immunoprecipitated with antiphosphotyrosine antibodies in most receptor systems studied, it has been examined that either ...

We reported previously that stimulation of RBL-2H3 cells through the high-affinity IgE receptor resulted in tyrosine phosphorylation of a 72-kDa protein (pp72) that was coupled to signal transduction. In the present study, although pp72 tyrosine phosphorylation was induced only by antigen triggering, stimulation of RBL-2H3 cells by either antigen or the calcium-ionophore A23187 led to increased...