Human brain cells use about one-fifth of the body’s energy. Scientists assume that neurons are energy hogs, but know little about how they manage those energy demands, says Timothy Ryan, a biochemist and neuroscientist at Weill Cornell Medical College. The energy needs of presynaptic nerve terminals must be addressed locally, as the synapse can be as far away as one meter from the cell body. Together with colleagues, Ryan has engineered an optical reporter system called Syn-ATP that, when expressed in neurons, can directly measure the number of ATP molecules specifically located at presynaptic nerve terminals.
“Visualizing cellular biochemical processes is one of the most difficult and exciting areas of neurobiology, and this technique is a successful example of this approach,” says neurobiologist Pietro De Camilli of Yale University. “It’s a powerful new tool.”
Using the reporter in cultured rat hippocampal cells, the researchers found that measured levels of ATP ...