adenilátciklázat

Adenilátcikláz, often abbreviated as AC or just adenylyl cyclase, is a crucial enzyme found in virtually all living organisms. It catalyzes the conversion of adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP) and pyrophosphate. This reaction is a fundamental step in signal transduction pathways.

The activity of adenilátcikláz is tightly regulated. It can be activated or inhibited by a variety of signaling molecules, including hormones and neurotransmitters. In many systems, G protein-coupled receptors (GPCRs) play a key role in modulating adenilátcikláz activity. Upon binding of a ligand to a GPCR, a specific G protein is activated, which then interacts with adenilátcikláz, either stimulating or inhibiting its catalytic function.

The cAMP produced by adenilátcikláz acts as a second messenger within the cell. It binds to and activates protein kinase A (PKA), a serine/threonine kinase. PKA then phosphorylates a wide range of target proteins, leading to diverse cellular responses. These responses can include changes in gene expression, enzyme activity, ion channel function, and cell growth and differentiation. Therefore, adenilátcikláz is central to cellular communication and the execution of many physiological processes. There are multiple isoforms of adenilátcikláz, each with distinct regulatory properties and tissue distribution, contributing to the complexity and specificity of cellular signaling.