Phosphorylation

Over the past two decades, it has become clear that tyrosine phosphorylation plays a pivotal role in a variety of important signaling pathways in multicellular organisms. In the typical vertebrate cell, phosphotyrosine represents only a tiny fraction of total protein phosphorylation. Yet it is sufficient enough to induce malignant transformation (1), as unregulated phosphotyrosine signaling causes a breakdown in the normal regulation of cellular processes leading to several human diseases (2).

Phosphotyrosine is the phosphorylated version of the amino acid tyrosine, which results from the activation of intracellular protein kinases (e.g. via growth factors) during normal growth and development, well as in transformation and oncogenesis. Phosphorylation of histidine, serine, threonine and tyrosine residues acts as a signaling system to control many cellular signaling pathways.

We at Novus Biologicals place a lot of emphasis on the kinase signaling pathways. Kinases, or phosphotransferase enzymes play a key role in phosphorylation signaling. Over 500 human protein kinases have so far been discovered. They play essential roles in glucose metabolism, apoptosis, lipid transport, cell migration, cellular differentiation and other cellular functions.