About this Research Topic
Cells are constantly out-of-equilibrium with their surroundings and require a constant influx of energy to remain in that state. Through intracellular membrane trafficking and complicated metabolic pathways, cells have evolved to efficiently transform the energy from their environment into energy storage molecules like ATP. Most of the energy is used to synthesize the biomolecules that provide cells with the tools to survive and interact with their environment. A great part of the remaining energy produced is used to move the cell around, incorporate material from the extracellular space, secrete signaling products, transport cargo along the interior of the cell, and recycle material when necessary. These processes are therefore exquisitely regulated by events where the limiting step requires the release of energy by ATP or GTP in a controlled manner.
A number of energy-dependent proteins can be found to be essential for all the steps involved in the intracellular traffic of cargo. From dynamin during endocytosis, to dynein-mediated movement of lysosomes, and snare-dependent fusion of organelles, ATP and GTP are highly utilized as cellular energy currency to keep a steady-state flux of cargo within organelles inside the cell. To advance our understanding of one of the most complex and widespread networks in biology, it is essential that classic and modern biochemical and cell biology approaches are combined with activity-based assays and advanced proteomics and microscopy techniques. In addition, the development of inhibitors to selectively control the hydrolysis state of ATPases, GTPases and their effectors allows for clear insight into these processes. Finally, it is clear that the dysregulation of the machineries involved in controlling traffic is frequently associated with diseases that include cancer, developmental and degenerative diseases and multiple immunity disorders.
The aim of this Research Topic is to cover recent and novel research trends in the intracellular trafficking field through Original Research and Reviews articles. Areas to be covered may include, but are not limited to:
• Molecular models of small-GTPase structure and function in homeostasis and disease (e.g. Rabs and Arfs and their GAPs and GEFs, membrane scission machinery etc.).
• ATPases in intracellular trafficking (e.g. AAA+ machines).
• Energetics of motor molecules like kinesins, dyneins and myosins.
• State-of-the-art techniques to address the function of energy-consumption in intracellular trafficking.
• Advanced proteomics and lipidomics tools of discovery.
• Manipulating small GTPases and ATPases as therapeutic strategies.
Keywords: ATP, GTP, Small GTPases, Motor Molecules, Membranes