ADP Ribosylation Factors (ARFs) are a family of small GTPases that play essential roles in intracellular vesicular trafficking and membrane dynamics. They are highly conserved proteins found in eukaryotic organisms, including humans. ARFs are involved in the regulation of numerous cellular processes, such as vesicle formation, cargo sorting, and fusion of intracellular membranes.
The function of ARFs relies on their ability to switch between an inactive GDP-bound state and an active GTP-bound state. This transition is facilitated by guanine nucleotide exchange factors (GEFs) that promote the exchange of GDP for GTP, leading to the activation of ARFs. Once activated, ARFs recruit specific effector proteins to the target membrane, initiating various cellular processes.
ARFs are particularly important in the formation and trafficking of vesicles from the Golgi apparatus, a cellular organelle involved in protein modification and sorting. They help regulate the assembly of coat protein complexes, such as COPI and clathrin, which aid in the budding of vesicles from the Golgi membrane. Additionally, ARFs have been implicated in the regulation of endocytosis, exocytosis, and the transport of membrane proteins between different cellular compartments.
Malfunctions in ARF signaling have been associated with various pathological conditions, including cancer, neurodegenerative disorders, and infectious diseases. Studies on ARFs and their associated pathways have revealed potential targets for therapeutic interventions aimed at modulating intracellular trafficking and membrane dynamics.
