Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Uncover Fragile X Syndrome Gene’s Role in Shaping Brain

11.05.2010
Researchers at UT Southwestern Medical Center have discovered how the genetic mutation that causes Fragile X syndrome, the most common form of inherited mental retardation, interferes with the “pruning” of nerve connections in the brain. Their findings appear in the April 29 issue of Neuron.

Soon after birth, the still-developing brain of a mammal produces too many nerve connections that create “noise” in the nervous system. The brain finds it hard to process these signals, like a person trying to have a conversation at a loud party. But as the brain matures and learning takes place, some nerve connections naturally become stronger while others weaken and die, leading to an adult with a properly wired brain.

Fragile X is caused by a mutation in a single gene, Fmr1, on the X chromosome. The gene codes for a protein called FMRP, which plays a role in learning and memory but whose full function is unknown. The protein’s role in pruning nerve connections had been unclear.

“I think we’ve uncovered a core function for the gene involved in this disease, and if we can find other biochemical methods involved in nerve pruning, we might be able to help correct this,” said Dr. Kimberly Huber, associate professor of neuroscience at UT Southwestern and senior author of the study.

In the current study, Dr. Huber and her colleagues examined nerve cells isolated from mice that had been engineered to lack the Fmr1 gene and, therefore, did not produce FMRP protein. They then tested whether the lack of FMRP affected the functions of another protein called MEF2, which is known to be involved in pruning nerve connections.

The researchers found that nerve cells lacking FMRP were unable to respond to MEF2. Adding FMRP to the cells restored MEF2’s normal function.

“We were massively activating the MEF2 gene in the cell, and it did absolutely nothing without FMRP,” Dr. Huber said. Such an all-or-nothing requirement in a biochemical relationship is rare, she said.

The findings also raise questions about how the two proteins interact physically. MEF2 works in the nucleus of a cell, where it controls whether other genes are turned on or off. FMRP shuttles in and out of the cell’s nucleus and into its main body.

“This opens up new ideas about how processes in the cell’s nucleus, near its DNA, can affect the nerve connections, which are very far away at the other end of the cell,” Dr. Huber said. “We think MEF2 is making messenger RNA [ribonucleic acid], which translates the genetic code of the DNA, and FMRP is binding to the RNA and either transporting it to the nerve connections and/or controlling how the RNA makes protein.”

Further research will focus on the relationship between the proteins. For instance, one might directly control the other, or they might work together on a common target, Dr. Huber said.

“This work might not have clinical implications for quite a while,” she said. “The goal for us as scientists is to understand how these genes relate to mechanisms that control the development of nerve connections.”

Like other genetic diseases carried on the X chromosome, Fragile X syndrome strikes boys more often and more severely than girls. Girls have two X chromosomes, so a normal gene on one chromosome can mitigate the effects of the disease if the gene on the other X chromosome is abnormal. Boys, however, have only one X chromosome, so if they inherit an abnormal gene on the X chromosome, they have no protection.

Other UT Southwestern researchers involved in the study were lead author and former graduate student Brad Pfeiffer; Dr. Tong Zang, postdoctoral researcher in neuroscience; Dr. Julia Wilkerson, postdoctoral researcher in neuroscience; Dr. Makoto Taniguchi, postdoctoral researcher in psychiatry; Marina Maksimova, research assistant in neuroscience; Dr. Laura Smith, postdoctoral researcher in psychiatry; and Dr. Christopher Cowan, assistant professor of psychiatry.

The study was funded by the National Institutes of Health, Autism Speaks, the Whitehall Foundation and Simons Foundation.

Aline McKenzie | Newswise Science News
Further information:
http://www.utsouthwestern.edu

Further reports about: Brain DNA FMR1 Gene’s MEF2 RNA Syndrome Uncover X chromosome cell’s nucleus genetic disease nerve cell

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Periodic ventilation keeps more pollen out than tilted-open windows

29.03.2017 | Health and Medicine

Researchers discover dust plays prominent role in nutrients of mountain forest ecoystems

29.03.2017 | Earth Sciences

OLED production facility from a single source

29.03.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>