How neurons lose their connections
Strengthening and weakening the connections between neurons, known as synapses, is vital to the brain’s development and everyday function. One way that neurons weaken their synapses is by swallowing up receptors on their surfaces that normally respond to glutamate, one of the brain’s excitatory chemicals. In a new study, MIT neuroscientists have detailed how this receptor reabsorption takes place, allowing neurons to get rid of unwanted connections and to dampen their sensitivity in cases of overexcitation. “Pulling in and putting out receptors is a dynamic process, and it’s highly regulated by a neuron’s environment,” says Elly Nedivi, a professor of brain and cognitive sciences and member of MIT’s Picower Institute for Learning and Memory. “Our understanding of how receptors are pulled in and how regulatory pathways impact that has been quite poor.” Nedivi and colleagues found that a protein known as CPG2 is key to this regulation, which is notable because mutations in...