Phosphorylation is an essential process in biological events and is considered critical for
biological functions. In tissues, protein phosphorylation mainly occurs on tyrosine (Tyr) …

At high concentrations, free radicals and radical-derived, nonradical reactive species are
hazardous for living organisms and damage all major cellular constituents. At moderate …

Protein phosphatases are the essential opposite to protein kinases; together, these enzymes
regulate all protein phosphorylation and most cellular processes. To better understand the …

There are many misconceptions surrounding the roles of protein phosphatases in the
regulation of signal transduction, perhaps the most damaging of which is the erroneous view …

A typical protein kinase must recognize between one and a few hundred bona fide
phosphorylation sites in a background of∼ 700,000 potentially phosphorylatable residues …

Publisher Summary The chapter introduces the mitogen-activated protein (MAP) kinase
(MAPK) module. The identification of MAP kinase pathways exemplifies the power of …

The structure of the SHP-2 tyrosine phosphatase, determined at 2.0 Å resolution, shows how
its catalytic activity is regulated by its two SH2 domains. In the absence of a tyrosine …

The tumor suppressor PTEN regulates cell migration, growth, and survival by removing the
3′-phosphate of phosphoinositides. Exposure of purified PTEN or of cells to H 2 O 2 …

The PTEN tumor suppressor is mutated in diverse human cancers and in hereditary cancer
predisposition syndromes. PTEN is a phosphatase that can act on both polypeptide and …

The second messenger hydrogen peroxide is required for optimal activation of numerous
signal transduction pathways, particularly those mediated by protein tyrosine kinases …