RAB4B

RAB4B is a gene that encodes a protein belonging to the Ras-related in brain (RAB) small GTPase family. These proteins are involved in regulating intracellular membrane trafficking. The RAB4B protein specifically is thought to play a role in the endosomal-lysosomal pathway, which is crucial for processes like nutrient uptake, waste removal, and receptor recycling.

The RAB4B protein acts as a molecular switch, cycling between an inactive GDP-bound state and an active GTP-bound state. This cycling is regulated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). When RAB4B is in its active GTP-bound form, it can bind to effector proteins that mediate the transport of vesicles along the endosomal pathway.

Dysregulation of RAB4B has been implicated in various cellular processes and potentially in diseases. Research suggests its involvement in cell migration and proliferation, and alterations in its expression or function have been observed in certain types of cancer. Further investigation is ongoing to fully elucidate the precise molecular mechanisms and physiological roles of RAB4B in both normal cellular function and disease pathogenesis. Its interaction with other RAB proteins and its specific contributions to different trafficking pathways remain areas of active study.