The DENN domain is a common, evolutionarily ancient, and conserved protein module, yet it
has gone largely unstudied; until recently, little was known regarding its functional roles.
New studies reveal that various DENN domains interact directly with members of the Rab
family of small GTPases and that DENN domains function enzymatically as Rab-specific
guanine nucleotide exchange factors. Thus, DENN domain proteins appear to be
generalized regulators of Rab function. Study of these proteins will provide new insights into …