GTPase activity

Definition

Target type: molecularfunction

Catalysis of the reaction: GTP + H2O = GDP + H+ + phosphate. [PMID:26832457, PMID:27218782]

GTPase activity is a fundamental molecular function that involves the hydrolysis of guanosine triphosphate (GTP) to guanosine diphosphate (GDP) and inorganic phosphate (Pi). This hydrolysis reaction is catalyzed by a class of enzymes known as GTPases. GTPases play crucial roles in a wide variety of cellular processes, including signal transduction, protein synthesis, vesicle trafficking, cytoskeletal dynamics, and cell cycle regulation. The GTPase cycle is a key regulatory mechanism that allows GTPases to switch between active and inactive conformations. In the active state, GTP is bound to the GTPase, and the protein is able to interact with its downstream effectors. Upon hydrolysis of GTP to GDP, the GTPase undergoes a conformational change, becoming inactive and releasing its effector. This cycle is often regulated by guanine nucleotide exchange factors (GEFs), which promote the exchange of GDP for GTP, and GTPase-activating proteins (GAPs), which stimulate the hydrolysis of GTP. GTPases are highly diverse and can be broadly classified into five families: small GTPases (Ras superfamily), heterotrimeric G proteins, dynamin-like GTPases, translation elongation factors, and AAA+ ATPases. Each family has specific structural features and regulatory mechanisms that contribute to their distinct functions. The GTPase cycle is a versatile molecular switch that enables GTPases to act as molecular timers, signaling relays, and regulators of protein-protein interactions. Their essential roles in numerous cellular processes highlight the importance of GTPase activity in maintaining cellular homeostasis and function.'
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Proteins (67)

Compounds (429)