Fifth-year graduate student Jaekyoon Kim is the first-author of a new study in the Journal of Neuroscience (Kim et al., 2016, J Neurosci, 36(11):3309-3321) that examined the role of the membrane estrogen receptor G-protein-coupled estrogen receptor (GPER) in mediating the memory-enhancing effects of estradiol in ovariectomized female mice.  Our previous work showed that activation of the canonical intracellular estrogen receptors, ERα and ERβ, in the dorsal hippocampus mimics the effects of dorsal hippocampal estradiol infusion on memory; like estradiol, agonists of ERα and ERβ enhance object recognition and spatial memory by increasing dorsal hippocampal ERK phosphorylation.  Our new paper demonstrates that although activation of GPER in the dorsal hippocampus also enhances object recognition and spatial memory, it does so by triggering c-Jun N-terminal kinase (JNK) signaling rather than ERK signaling.  Moreover, the ability of estradiol to enhance hippocampal memory was not dependent on either JNK or GPER activation, indicating that estradiol and GPER independently regulate hippocampal memory.  These data suggest the intriguing conclusion that GPER does not function as an estrogen receptor in the dorsal hippocampus to regulate memory consolidation.