fehérjeszorzót

A fehérjeszorzót, or protein kinase, is a type of enzyme that facilitates and regulates the expression of genes and signal transduction by adding a phosphate group to its substrate protein. This process is known as phosphorylation. Protein kinases are crucial for a vast array of cellular processes, including cell division, cell growth, cell differentiation, and programmed cell death.

The phosphorylation event typically occurs at specific amino acid residues on the target protein, most commonly serine, threonine, or tyrosine. This addition of a phosphate group can alter the protein's conformation, activity, or its ability to interact with other molecules. These changes are often reversible, with phosphatases acting as the opposing enzymes that remove phosphate groups.

The human genome encodes over 500 different protein kinases, highlighting their extensive roles in cellular regulation. Aberrant kinase activity is implicated in numerous diseases, particularly cancer, where mutations or dysregulation of kinases can lead to uncontrolled cell proliferation and survival. Consequently, protein kinases are significant targets for drug development, with many approved cancer therapies being kinase inhibitors. The study of protein kinases, often referred to as "kinomics," is a vital area of molecular biology and pharmacology.