Türosiinkinaase

Türosiinkinaas, also known as tyrosine kinase, is a crucial enzyme class that catalyzes the transfer of a phosphate group from ATP to a tyrosine residue on a substrate protein. This phosphorylation event is a key regulatory mechanism in cellular signaling pathways. Tyrosine kinases play vital roles in a wide array of cellular processes, including cell growth, differentiation, proliferation, survival, and migration. Their aberrant activity is frequently implicated in the development and progression of various diseases, most notably cancer.

There are two main categories of tyrosine kinases: receptor tyrosine kinases (RTKs) and non-receptor tyrosine kinases (NRTKs). RTKs are transmembrane proteins that have an extracellular ligand-binding domain and an intracellular catalytic domain. Upon binding of a specific growth factor or hormone, RTKs dimerize and activate their kinase activity, initiating downstream signaling cascades. NRTKs, on the other hand, are located in the cytoplasm or nucleus and are activated by various upstream signals.

The dysregulation of tyrosine kinase activity can lead to uncontrolled cell proliferation and survival, which are hallmarks of cancer. Many targeted cancer therapies, known as tyrosine kinase inhibitors (TKIs), have been developed to block the activity of specific tyrosine kinases that drive tumor growth. These drugs have revolutionized the treatment of several types of cancer, offering improved outcomes for patients. Research continues to explore the complex roles of tyrosine kinases in health and disease, aiming to identify new therapeutic targets and develop more effective treatments.