Protein kinases transfer phosphate groups from ATP to serine, threonine, or tyrosine residues on protein peptide substrates, directly affecting the activity and function of the target. Radiolabel studies suggest that approximately 30% of proteins in eukaryotic cells are subject to phosphorylation. Kinase activity, a crucial post-translational modification, regulates a broad range of cellular activities including the cell cycle, differentiation, metabolism, and neuronal communication. In addition, abnormal activity of Akt, ERK, JNK, PKC, PKA, p38, and other MAPK are implicated in many disease states. Sino Biological Inc. offers a range of quality products for the detection of protein phosphorylation, which include kinase activity assays, phospho-specific antibodies, ELISA, and more.
Extracellular signals, such as hormones, neurotransmitters, and growth factors, regulate a wide variety of cellular activities, including ion channel modulation, neuronal excitation, cell growth, cell differentiation, and insulin secretion events (1). Intracellular transduction systems receive these signals via receptors and transmit them quickly and precisely, resulting in the amplification of specific biological responses. However, cells often are exposed to several messengers simultaneously, and maintaining the fidelity of these networks is crucial in eliciting the appropriate physiological response. Doing so requires the accurate selection of effector molecules for regulated activation and deactivation, often by phosphorylation and dephosphorylation events. A principal strategy in achieving this selection specificity is compartmentalization of signaling enzymes