A competitive game of synaptic tag

LTP maintenance is thought to require an activity-dependent "synaptic tag" that allows potentiated synapses to sequester factors necessary for maintenance. In a paper in this issue of Neuron, Fonseca et al. show that synapses can compete with each other for such maintenance factors, so that additional potentiation of one input results in loss of potentiation of another. These data suggest that LTP maintenance is a dynamic and competitive process.