Signal transduction tyrosine kinases

Post-kinase Signal Transduction Tyrosine-phosphorylated Proteins. 34... 

POST-KINASE SIGNAL TRANSDUCTION TYROSINE-PHOSPHORYLATED PROTEINS... 

Sorafenib is a multitargeted cancer therapy that inhibits VEGFR, PDGFR, KIT, fetal liver tyrosine kinase 3 (FLT-3), and the serine/threonine kinase RAF. RAF kinase is a key downstream effector of Ras in the MAPK/Ras signal-transduction pathway that has been linked to various cancers. Sorafenib is both a tyrosine kinase inhibitor and serine/threonine signal-transduction inhibitor. Sorafenib has been approved in renal cancer. 

In contrast to tyrosine kinases, Tyrosine phosphatases (PTPs) are enzymes which act on phosphorylated proteins and catalyze the transfer of a phosphate group from a tyrosine residue to a water molecule, generating orthophosphates in a process which is referred to as dephosphorylation. PTPs are involved in many cellular signal transduction pathways. 

One main line of future research could be in the inhibitory/activating effect on key enzymes involved in the pathogenesis of arteriosclerosis. In particular, enzymes regulating signal transduction involved in phosphorylation of proteins, such as PKC and tyrosine protein kinase, seems to be somehow modulated by different polyphenols and may represent a possible target for polyphenol activity. 

Veillette A, Bookman MA, Horak EM, Samelson LE, Bolen JB. Signal transduction through the CD4 receptor involves the activation of the internal membrane tyrosine-protein kinase p561ck. Nature 1989 338(6212) 257—259. 

Ullrich, A., and Schlessinger, J. (1990). Signal transduction by receptors with tyrosine kinase activity. Cell 61 203-212. 

Signal Transduction through Protein Tyrosine Kinases... 

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