Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Team led by Scripps Research scientist identifies new gene for memory

09.09.2010
The findings could shed new light on human learning and neurological and psychiatric disorders

A team led by a Scripps Research Institute scientist has for the first time identified a new gene that is required for memory formation in Drosophila, the common fruit fly. The gene may have similar functions in humans, shedding light on neurological disorders such as Alzheimer's disease or human learning disabilities.

The study was published in the September 9, 2010 edition (Vol. 67, No. 5) of the journal Neuron.

"This is the first time we have a new memory and learning gene that lies outside what has been considered the most fundamental signaling pathway that underlies learning in the fruit fly," said Ron Davis, chair of Scripps Research Department of Neuroscience who led the study. "Since many of the learning and memory genes originally identified in the fruit fly are clearly involved in human neurological or psychiatric diseases, this discovery may offer significant new insights into multiple neurological disorders. We're definitely in the right ballpark."

The study shows that different alleles or mutant forms of the gene, known as gilgamesh (gish), are required for short-term memory formation in Drosophila olfactory associative learning – learning that links a specific odor with a negative or positive reinforcer.

Because Drosophila learning genes are known to be conserved in higher organisms including humans, they often provide new insights into human brain disorders. For example, the Drosophila gene known as dunce, which Davis helped identify several years ago, provided clues to the genetics of the devastating psychiatric condition of schizophrenia. Recent studies have revealed that the human version of the dunce gene is a susceptibility determinant for schizophrenia. In a similar way, any new learning gene identified in Drosophila, including gilgamesh, may provide new clues to genes involved in human neurological or psychiatric disorders.

"We're still early in the process of making connections between Drosophila memory and learning genes and the pathology of human disease," Davis said, "but it's already clear that many of these genes will provide important conceptual information and potential insights into human brain disorders. In addition, there is every reason to believe that their gene products will be one day become the target of new drugs to enhance cognition. Uncovering this new gene and its signaling pathway helps bring us that much closer to this goal."

New Gene, New Pathway

To identify the new gene, Davis and his colleagues used a novel screen for new memory mutants, looking for lines that showed abnormal learning when only one of two copies of the gene was mutant.

"We used a dominant screen because we realized that behavior such as learning and memory are very sensitive to gene dosage," Davis said. "That is, the mutation of just one copy of a gene involved in behavior is often sufficient to produce an abnormality."

The formation of new memories occurs, in part, through the activation of molecular signaling pathways within neurons that comprise the neural circuitry for learning, and for storing and retrieving those memories.

One of the things that makes the function of gish so interesting, Davis noted, is the fact that it is independent of mutations of the rutabaga gene, a Drosophila memory-learning pathway that is known to be essential for memory formation. The rutabaga mutants convert ATP, the energy chip of cells, into cyclic AMP or cAMP, which plays a critical role in olfactory learning in Drosophila.

"The cAMP pathway is the major signaling pathway used by Drosophila neurons to turn on other enzymes and genes that are necessary for memories to form," Davis said. "In fruit flies, memory and learning revolves around mutants of this pathway. It is fundamental to the process."

In the new study, gish provided an answer to a longstanding problem in Drosophila learning and memory research – the unexplained residual memory performance of flies carrying rutabaga mutations, which indicated the existence of an independent signaling pathway for memory formation. While other memory mutants have been identified, until the discovery of gish none have been shown to reduce the residual learning of mutant rutabaga flies.

Interestingly, the study found that the gish gene encodes a kind of casein kinase (which help regulate signal pathways in cells) called Iã (CKIã). This is the first time that this specific kinase has been cited as having a role in memory formation.

The identification of all signaling pathways that are engaged in specific neurons during memory formation and how they interact with one another to encode memories is an issue of great importance, Davis said, one that needs more exploration for a deeper understanding of memory formation and memory failure in humans.

"The truth is that we have an extremely sketchy understanding of what causes diseases like Alzheimer's," Davis said. "We need to understand a lot more than we do now about normal brain functions like memory and learning before we have a high probability of succeeding in the development of a cure."

###

The first author of the study, "Gilgamesh is required for Rutabaga-independent Olfactory Learning in Drosophila," is Ying Tan of Baylor College of Medicine. Other authors include Dinghui Yu and Jennifer Pletting of Baylor College of Medicine.

The study was supported by the National Institutes of Health.

About The Scripps Research Institute

The Scripps Research Institute is one of the world's largest independent, non-profit biomedical research organizations, at the forefront of basic biomedical science that seeks to comprehend the most fundamental processes of life. Scripps Research is internationally recognized for its discoveries in immunology, molecular and cellular biology, chemistry, neurosciences, autoimmune, cardiovascular, and infectious diseases, and synthetic vaccine development. An institution that evolved from the Scripps Metabolic Clinic founded by philanthropist Ellen Browning Scripps in 1924, Scripps Research currently employs approximately 3,000 scientists, postdoctoral fellows, scientific and other technicians, doctoral degree graduate students, and administrative and technical support personnel. Headquartered in La Jolla, California, the institute also includes Scripps Florida, whose researchers focus on basic biomedical science, drug discovery, and technology development. Scripps Florida is located in Jupiter, Florida. For more information, see www.scripps.edu

Mika Ono | EurekAlert!
Further information:
http://www.scripps.edu

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>