A study by Johns Hopkins researchers has shown that a widely
accepted model of long-term memory formation — that it hinges on
a single enzyme in the brain — is flawed. The new study,
published in the Jan. 2 issue of Nature, found that mice lacking
the enzyme that purportedly builds memory were in fact still
able to form long-term memories as well as normal mice could.
"The prevailing theory is that when you learn something, you
strengthen connections between your brain cells called
synapses," explains Richard Huganir, Ph.D., a professor and
director of the Johns Hopkins University School of Medicine's
Department of Neuroscience. "The question is, how exactly does
this strengthening happen?" A research group at SUNY Downstate,
led by Todd Sacktor, Ph.D., has suggested that key to the
process is an enzyme they discovered, known as PKM-zeta. In
2006, Sacktor's group made waves when it created a molecule that
seemed to block the action of PKM-zeta — and only PKM-zeta. When
the molecule, dubbed ZIP, was given to m