Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Discover New Gene Essential For The Development Of Normal Brain Connections Resulting From Sensory Input

09.01.2004


Biologists at the University of California, San Diego and the Johns Hopkins University have discovered a gene that plays a key role in initiating changes in the brain in response to sensory experience, a finding that may provide insight into certain types of learning disorders.


Images of neurons from normal mice (left) and from mice lacking CREST gene (right) Credit: Anirvan Ghosh



After birth, learning and experience change the architecture of the brain dramatically. The structure of individual neurons, or nerve cells, changes during learning to accommodate new connections between neurons. Neuroscientists believe these structural changes are initiated when neurons are activated, causing calcium ions to flow into cells and alter the activity of genes.

In a paper featured on the cover of the January 9th issue of the journal Science, biologists at UCSD and the Johns Hopkins University medical school report the discovery of the first gene, CREST, known to mediate these changes in the structure of neurons in response to calcium.


“We discovered the gene CREST using a new method we developed to identify genes that are switched on in the presence of calcium,” says Anirvan Ghosh, a professor of biology at UCSD who headed the study. “The brains of mice lacking CREST appear normal at birth, but do not develop normally in response to sensory experience after birth. This parallels some learning disorders in humans where the child appears normal initially, but by the age of two or three years it becomes clear that there are failures in the acquisition of new knowledge.”

Neurons from normal mice develop a highly branched tree-like structure. In fact, much of the growth of the brain that occurs soon after birth is the development and branching of dendrites—the part of a nerve cell that receives input from other neurons. Thus, this branching allows neurons to form many different synapses, or connections, with many other neurons, permitting much cross talk between them. Neurons taken from mice lacking the CREST gene are more linear, like a plant shoot.

In addition, when individual neurons kept alive in a Petri dish are stimulated with calcium ions, they respond by developing highly branched dendrites, but neurons taken from mice lacking CREST fail to branch in response to calcium.

“CREST is the first example of a transcription factor—a protein that turns genes on and off—that appears to be specifically required for the development of brain neurons after birth," explains Ghosh, who conducted the study at his former laboratory at Johns Hopkins.

His new laboratory at UCSD is currently working to determine what gene is targeted by CREST. Ghosh suspects the CREST gene might be turning on the production of chemicals called growth factors, for the stimulatory effect they have on cell development.

The CREST protein produced by that gene is made in several regions of the brain immediately after birth. In adults, the protein is produced in a region of the brain known as the hippocampus, which plays an important role in learning and memory. Because of this, Ghosh suspects that CREST may be necessary for the storage of new memories and the ability to learn. His laboratory is currently developing mice in which CREST expression is normal throughout most of development, so the brain develops normally, but then shuts off in the hippocampus when the mice reach adulthood. In this way, the researchers can test the specific role of CREST in learning and memory in adults.

“Humans also have CREST, and the CREST gene sequence is highly similar between mice and humans,” says Ghosh. “If it turns out that CREST plays a role in learning and memory in the mouse, then it is very likely it also plays a similar role in humans.”

The other researchers involved in the study are Hiroyuki Aizawa, Shu-Ching Hu, Kathryn Bobb, Karthik Balakriashnan, Inga Gurevich and Mitra Cowan. The study was supported by the National Institutes of Health, the March of Dimes Birth Defects Foundation, the Klingenstein Foundation, Merck and the Uehara Memorial Foundation.


Media Contact: Sherry Seethaler (858) 534-4656
Comment: Anirvan Ghosh (858) 822-4142

Sherry Seethaler | UCSD
Further information:
http://ucsdnews.ucsd.edu/newsrel/science/screst.asp

More articles from Life Sciences:

nachricht A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>