HOUSTON - (Nov. 6, 2008)- Memories turned on and off with a flick of a switch - the idea is the basis for the award winning research of Dr. Mauro Costa-Mattioli, assistant professor of neuroscience at Baylor College of Medicine in Houston.
Costa-Mattioli is being honored with the prestigious Eppendorf and Science Prize for Neurobiology for his work identifying a single molecule that when modified can affect memory.
His findings are outlined in his winning essay titled "Switching memories ON and OFF" that can be found in the current publication of Science.
"This is certainly one of the first steps to one day being able to help those suffering from age-related memory loss or even the more devastating memory loss caused by Alzheimer's disease," Costa-Mattioli said. "It is imperative to understand how the brain's basic molecular processes function to generate corresponding insights in cognitive disorders."
It is well known that making long-lasting memories is dependent on the ability of brain cells to create new proteins. Costa-Mattioli found that by reducing activity of a key protein called translation initiation factor 2 alpha, eiF2α, the expression of genes and proteins needed for the formation of a long-lasting memory is increased. Costa-Mattioli and colleagues genetically reduced eiF2α activity in mice. The test mice were then tested in a variety of behavioral paradigms. For instance, to study spatial memory, which underlie our ability to remember people, events and a particular environment; mice were trained in the Morris Water. In this task, mice swimming in a pool of opaque water search for a submerged platform. The mice used visual cues that are placed on the walls of the room to remember the location of the platform.
The mice with reduced activity of eiF2α were able to find the platform significantly faster than the average mice.
"Unlike normal mice, mice with decreased eIF2α activity knew exactly where the platform was located and swam straight towards it," he said.
Researchers also looked at the strength of the connections between neurons, called synapse, what is believed to be a "cellular model" to study learning and memory. Usually weak stimulation elicits a short lasting response or a transient enhancement of such synaptic connections, while strong or repeated activity triggers a long-lasting persistent enhancement of the strength of synaptic connections. Strikingly, in the test mice weak stimulation induced longer lasting strengthening of the synaptic connections between neurons, indicating that a short exposure to a given experience created long term memories.
"It usually takes several attempts to memorize a passage of a textbook, practice makes it perfect" Costa-Mattioli said. "A human equivalent of these mice would get the information if he reads it just once."
An important aspect of Costa-Mattioli's studies is that treatment of mice with a drug which increases the activity of eIF2α block the formation of long-lasting changes and long-term memory.
"The ability to erase specific memories would be crucial in the treatment of patients suffering from traumatic memories such as post-traumantic stress disorder," he said.
Dr. Michael Friedlander, chair of the department of neuroscience at BCM and the director of Neuroscience Initiatives at the College, said, "We are extremely fortunate to have recruited Dr. Costa-Mattioli to BCM. His recent discoveries on the role of specific protein synthesis in the conversion of short-term to long-term memories have dramatically re-awakened the world neuroscience community's interest in this critical molecular process. These new insights will drive experimental innovation in basic neurobiology of memory and diseases such as Alzheimer's that rob us of this most precious function."
Costa-Mattioli's recruitment to Houston was supported by the Cynthia and George Mitchell Foundation. He joins a growing memory research community in the Department of Neuroscience and in the new Mitchell Center for Brain Aging and Dementia and the Center for Memory and Learning at BCM.
Costa-Mattioli's studies were started at McGill University in Canada in the laboratory of Nahum Sonenberg.
The Eppendorf and Science Prize for Neurobiology acknowledges the role of neurobiology in advancing our understanding of the functioning of the brain and the nervous system. It is awarded annually for the most outstanding neurobiological research by a young scientist.
The award ceremony will be held in Washington, D.C. on Nov. 16.
Once the embargo lifts the essay can be found at http://www.sciencemag.org/.
For more information on basic science research at Baylor College of Medicine, please go to www.bcm.edu/fromthelab.
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Science