The protein kalirin-7 is responsible for triggering the remodeling of neuronal connections that is critical for learning, which, when malfunctioning, play a role in mental retardation, schizophrenia, and drug addiction, according to scientists at Northwestern University Feinberg School of Medicine.
The researchers sought to understand the biological machinery controlling the enlargement of dendritic spines on mature neurons when they undergo a learning-related strengthening process called long-term potentiation (LTP). The spines are the receiving stations for neurotransmitters. The enlargement of the spines strengthens signaling between neurons.
Experiments with cultured neurons revealed that activation of neurons during LTP triggers kalirin-7 to turn on the machinery for remodeling spines, causing spines to become enlarged.
The researchers also found that kalirin-7 controls the number of neurotransmitter receptors, which is the other major process necessary for strengthening neuronal signaling connections.
The study is published in the November 21, 2007, issue of Neuron.