Mechanism may explain aspects of brain impairment seen in Fragile X Syndrome
June 9, 2008Scientists report that a protein associated with a common form of mental retardation plays an important role in intracellular trafficking within neurons. The research, published by Cell Press in the June issue of the journal Developmental Cell, reveals new information about how neuronal communication and plasticity are affected in Fragile X Syndrome (FXS).
FXS is a highly prevalent form of inherited mental impairment that also contributes to autism spectrum disorders. Most people with fragile X have a mutation that interferes with production of fragile X mental retardation protein (FMRP). FMRP binds to certain messenger RNAs (mRNAs), molecules that serve as chemical blueprints for production of proteins. Although FMRP targets mRNAs known to be critical for neuronal development and plasticity, exactly how FMRP influences these mRNAs was not well understood.
Neurons extend tendrils called "dendrites" outward from the main body of the cell so that they can communicate with other neuronal cells. These sites of communication, called "synapses", are important for learning and memory. Many neurons normally respond to stimuli, including synaptic signals from other neurons, by shunting certain key mRNAs to their dendrites. Study author Dr. Jason Dictenberg from City University of New York and colleagues, including Dr. Gary J. Bassell from Emory University, used high resolution fluorescence imaging methods in cultured neurons from embryonic mouse brain to explore how FMRP affects the intracellular localization of several target mRNAs in response to neuronal stimulation.
The researchers found that neurons lacking FMRP could not properly traffic mRNAs in response to stimuli. FMRP appeared to act as an adaptor for motor molecules involved in mRNA transport. Importantly, acute suppression of FMRP transport in normal neurons resulted in both diminished mRNA transport and a significant increase in the length and number of dendritic outgrowths called spine protrusions. This phenotype is similar to what is seen in the mouse model and in humans with FXS.
These results suggest that defects in stimulus-induced synaptic localization of FMRP target mRNAs may make a significant contribution to the synaptic and cognitive defects observed in FXS. "The present study has identified several key FMRP targets that are dysregulated in dendrites and may provide insight into new therapeutics for the treatment of FXS that target the mRNA localization pathway and its signaling components," concludes Dr. Bassell.
Source: Cell Press
-
Study links Fragile X Syndrome proteins and RNA editing mistakes at nerve-muscle junction
Oct 30, 2011 |
5 / 5 (1) |
0
-
Workings of brain protein suggest therapies for inherited intellectual disability, autism
Jul 21, 2011 |
4 / 5 (2) |
0
-
Fragile X protein acts as toggle switch in brain cells
Jun 09, 2011 |
5 / 5 (2) |
0
-
'GPS system' for protein synthesis in nerve cells gives clues for understanding brain disorders
Mar 09, 2011 |
not rated yet |
0
-
Fragile X protein loss alters brain pathways responsible for learning and memory
Apr 08, 2010 |
5 / 5 (2) |
0
-
Engineers build first sub-10-nm carbon nanotube transistor
Feb 01, 2012 |
4.9 / 5 (33) |
30
-
Something old, something new: Evolution and the structural divergence of duplicate genes
Jan 31, 2012 |
4.6 / 5 (7) |
1
-
The hidden nanoworld of ice crystals: Revealing the dynamic behavior of quasi-liquid layers
Jan 30, 2012 |
5 / 5 (4) |
1
-
Stock market network reveals investor clustering
Jan 27, 2012 |
3.9 / 5 (23) |
8
-
Of microchemistry and molecules: Electronic microfluidic device synthesizes biocompatible probes
Jan 26, 2012 |
5 / 5 (2) |
0
-
Is Everyday Technology Killing Us?
Feb 08, 2012
-
Exercise and weight loss
Feb 08, 2012
-
Why do we have head aches? Our brains can't feel anything.
Feb 07, 2012
-
"The end of diseases" by David Agus, interview from Daily Show with Jon Stewart
Feb 04, 2012
-
Oncolytic adenovirus
Feb 04, 2012
-
Nutrition label stuffs and diets
Feb 02, 2012
- More from Physics Forums - Medical Sciences
More news stories
Starve a virus, feed a cure? Findings show how some cells protect themselves against HIV
A protein that protects some of our immune cells from the most common and virulent form of HIV works by starving the virus of the molecular building blocks that it needs to replicate, according to research published online ...
11 hours ago |
5 / 5 (2) |
0
|
Overeating may double risk of memory loss
New research suggests that consuming between 2,100 and 6,000 calories per day may double the risk of memory loss, or mild cognitive impairment (MCI), among people age 70 and older. The study was released today and will be ...
Medicine & Health / Neuroscience
7 hours ago |
5 / 5 (2) |
0
|
Injured boomers beware: Know when to see doctor
(AP) -- It happened to nurse Jane Byron years after an in-line skating fall, business owner Haralee Weintraub while doing "men's" push-ups, and avid cyclist Gene Wilberg while lifting a heavy box.
12 hours ago |
5 / 5 (1) |
0
Declining health-care productivity in England: Who says so?
Reports that the National Health Service in England has been declining in productivity in the last decade appear to have been accepted as fact. However, a Viewpoint published Online First by The Lancet disputes this. The Vi ...
5 hours ago |
1 / 5 (1) |
0
FDA-approved drug rapidly clears amyloid from the brain, reverses Alzheimer's symptoms in mice
Neuroscientists at Case Western Reserve University School of Medicine have made a dramatic breakthrough in their efforts to find a cure for Alzheimer's disease. The researchers' findings, published in the journal Science, show t ...
Medicine & Health / Neuroscience
Feb 09, 2012 |
4.9 / 5 (58) |
17
|
Scientists discover molecular secrets of 2,000-year-old Chinese herbal remedy
For roughly two thousand years, Chinese herbalists have treated Malaria using a root extract, commonly known as Chang Shan, from a type of hydrangea that grows in Tibet and Nepal. More recent studies suggest that halofuginone, ...
New method to examine batteries -- MRI from the inside
There is an ever-increasing need for advanced batteries for portable electronics, such as phones, cameras, and music players, but also to power electric vehicles and to facilitate the distribution and storage of energy derived ...
Google might launch Drive for cloud storage soon
(PhysOrg.com) -- Google's next big move, according to the Wall Street Journal, is a cloud storage service called Drive. Hardly first to the plate, Google is simply catching up to introducing its cloud reposi ...
A mitosis mystery solved: How chromosomes align perfectly in a dividing cell
Although the process of mitotic cell division has been studied intensely for more than 50 years, Whitehead Institute researchers have only now solved the mystery of how cells correctly align their chromosomes during symmetric ...
Lab study raises questions over nano-particle impact
Tests involving chickens have raised questions about the impact on health from engineered nano-particles, the ultra-fine grains commonly used in drugs and processed foods, scientists said on Sunday.
Researchers find extensive RNA editing in human transcriptome
In a new study published online in Nature Biotechnology, researchers from BGI, the world's largest genomics organization, reported the evidence of extensive RNA editing in a human cell line by analysis of RNA-seq data, demons ...