Cyclic AMP Dependent Protein Kinase (also known as protein kinase A or PKA) is an important enzyme involved in cellular signal transduction and regulation. It is activated by cyclic adenosine monophosphate (cAMP), which is a secondary messenger molecule produced in response to various stimuli.
PKA is a serine/threonine kinase, meaning it phosphorylates target proteins on specific serine and threonine residues. When activated by cAMP, PKA is released from its inactive tetrameric form and becomes a catalytically active holoenzyme with two catalytic subunits and two regulatory subunits.
The main function of PKA is to mediate the cellular response to cAMP signaling pathways and regulate numerous cellular processes. It acts on a wide range of target proteins, including enzymes, ion channels, and transcription factors, by phosphorylating them and modifying their activity or function.
PKA is involved in various physiological processes such as metabolic regulation, cell growth and proliferation, neuronal signaling, and hormone secretion. It plays a crucial role in intracellular signal transduction cascades triggered by hormones, neurotransmitters, and other external stimuli.
Abnormal regulation of PKA activity has been implicated in numerous diseases, including cancer, cardiovascular diseases, and neurological disorders. Hence, PKA serves as a potential therapeutic target for developing drugs to modulate its activity and modify the aberrant signaling pathways associated with these diseases.
In summary, cyclic AMP Dependent Protein Kinase (PKA) is an enzyme that plays a pivotal role in cellular signaling and regulation by phosphorylating target proteins in response to cAMP activation, thereby modulating various cellular processes and maintaining physiological homeostasis.
