The findings of two recent studies involving the genes of fruit flies may provide clues that will help researchers better understand Alzheimer's disease.

As highlighted in the Feb. 18 issue of Current Biology, researchers at Cold Spring Harbor Laboratory in New York identified dozens of genes required for long-term memory that might be involved in human learning. They also identified another large group of memory genes that are either switched on or off in the fly brain during memory formation.

According to the researchers, many of the fruit fly genes they uncovered have counterparts in humans. Because these genes might be involved in human learning and memory, they may be important for understanding human memory deficit disorders such as Alzheimer's disease. The genes are also potential targets for the development of therapies to treat such disorders.

Previous studies have shown that boosting the expression level in the fly brain of a gene called CREB provides flies a form of photographic memory. Preliminary research now indicates that drugs that boost the expression level of the mouse CREB gene can improve memory in mice. Human memory, particularly in patients with Alzheimer's disease, may well be improved by the same kind of drug, according to the researchers.

Meanwhile, researchers at Brown University and the Salk Institute for Biological Studies found a new genetic mutation that prompts adult fruit flies to develop symptoms similar to Alzheimer's disease.

"This is the first fruit fly mutant to show some of the outward, physical manifestations common to certain major human neurodegenerative diseases," said lead researcher Michael McKeown, a biology professor at Brown University.

The researchers found the mutation in a gene they named "blue cheese." Reporting in the Feb. 15 issue of the Journal of Neuroscience, the researchers describe blue cheese mutations that lead normal-appearing adult flies to die early from extensive cell death in the brain, neural degeneration and build-up of protein aggregates.

According to study author Kim D. Finley, a biologist at the Salk Institute for Biological Studies, the fruit fly genes contain the same proteins that are the major components of plaques that form in the brains of human Alzheimer's patients.

"The presence of these proteins in human plaques is at times used as a diagnostic tool for Alzheimer's disease," Finley said, noting that the findings may provide new insights that could result in potential treatments of these disorders.

Other sources: Cold Spring Harbor Laboratory, Brown University