The molecular organization of cerebellar long-term depression

Synaptic plasticity is an important cellular mechanism for the formation of memory in neuronal circuits of the brain. Research during the past two decades has revealed surprisingly complex signal-transduction processes that underlie various forms of synaptic plasticity. More than 30 molecules are involved in the induction of long-term depression (LTD)-a unique form of synaptic plasticity in the cerebellum. Here, I review recent data on these molecules, defining their roles as mediators or modulators, coincidence detectors or components of a self-regenerating circuit, and show how they are organized to form an efficient molecular machinery for LTD induction.