GTPases are proteins that bind and hydrolyse GTP and act as bimodal switchs that alternates between inactive GDP-bound, and active GTP-bound confirmation to trigger a cellular response. They regulate numerous cellular processes, including signal transduction, cell growth and differentiation, ribosome assembly and protein synthesis, cytoskeletal organization, nuclear transport and spindle assembly, and intracellular protein transport. (Adapted from
PMID:2122258).