AKTS

AKTs, or Akt kinases, are a family of serine/threonine protein kinases that play a crucial role in cell signaling, particularly in response to growth factors and other extracellular stimuli. They are activated by phosphorylation on specific residues, typically Thr308 and Ser473, which are located in the activation loop of the kinase domain. Once activated, AKTs phosphorylate a variety of substrates, including Bad, FOXO, and GSK-3β, leading to changes in cell survival, proliferation, and metabolism.

AKTs are divided into three main isoforms: Akt1, Akt2, and Akt3. Akt1 is the most widely studied and is often referred to as the prototypical Akt. Akt2 and Akt3 have more limited tissue distribution and are less well understood. All three isoforms are activated by the phosphatidylinositol 3-kinase (PI3K) pathway, which is a critical regulator of cell growth and survival.

AKTs are involved in numerous cellular processes, including cell cycle progression, apoptosis, and metabolism. They are also implicated in various diseases, such as cancer, diabetes, and cardiovascular disease. For instance, Akt activation is often dysregulated in cancer cells, leading to increased cell survival and proliferation. In diabetes, Akt activation contributes to insulin resistance and glucose intolerance. In cardiovascular disease, Akt activation is associated with hypertension and heart failure.

AKTs are regulated by a variety of mechanisms, including phosphorylation, ubiquitination, and interaction with other proteins. For example, Akt can be phosphorylated by PDK1 and mTORC2, leading to its activation. Conversely, Akt can be deactivated by phosphatases, such as PP2A and PTEN, and by ubiquitination and proteasomal degradation.

In summary, AKTs are a family of serine/threonine protein kinases that play a critical role in cell signaling and are involved in various cellular processes and diseases. They are regulated by a variety of mechanisms and are a promising target for therapeutic intervention in several diseases.