GTPázával

GTPázával is a term that can refer to a family of enzymes known as GTPases. GTPases are enzymes that bind to and hydrolyze guanosine triphosphate (GTP), a molecule that plays a crucial role in various cellular processes. This hydrolysis releases energy that can be used to drive other cellular reactions, or the GTPase can act as a molecular switch.

There are two main classes of GTPases: the smaller, monomeric GTPases and the larger, heterotrimeric G proteins. Monomeric GTPases, such as the Ras superfamily, are involved in regulating cell growth, differentiation, and intracellular transport. Heterotrimeric G proteins, on the other hand, are primarily associated with cell surface receptors, mediating signal transduction pathways in response to external stimuli like hormones and neurotransmitters.

The function of GTPases is often regulated by their ability to switch between an active, GTP-bound state and an inactive, GDP-bound state. Guanine nucleotide exchange factors (GEFs) promote the exchange of GDP for GTP, activating the GTPase, while GTPase-activating proteins (GAPs) accelerate the hydrolysis of GTP to GDP, inactivating the GTPase. This dynamic cycle allows GTPases to act as signal integrators and regulators within the cell. Dysregulation of GTPase activity is implicated in a variety of diseases, including cancer and developmental disorders.