Navigation Links
Toxic molecule may cause most common type of muscular dystrophy

Doctors at the University of Virginia Health System have shown for the first time that getting rid of poisonous RNA (ribonucleic acid) in muscle cells can reverse myotonic dystrophy, the most common type of muscular dystrophy in adults.

About 40,000 people in the United States have myotonic muscular dystrophy (MMD). The disease can cause a slow, progressive wasting of the muscles, irregular heartbeat, cataracts and insulin resistance. Many people don't know they have MMD until their teens or twenties.

To prove the theory that toxic RNA is involved in myotonic muscular dystrophy, a research team led by Dr. Mani Mahadevan, a UVa pathologist, duplicated the disease in mice. "We showed in our mouse model that when you make this poisonous RNA the mice get various aspects of myotonic dystrophy," Mahadevan said. "Then, when you take away the toxic RNA, the mice get back to normal."

Mahadevan hopes the research might lead to new therapies for MMD in the next few years. "If we develop a therapy to silence the expression of the toxic RNA molecule, that would be a viable approach to treat people with myotonic muscular dystrophy," he said. Mahadevan's research in published in the September 2006 issue of Nature Genetics and can be found online at: http://www.nature.com/ng/index.html

Making RNA is the second step in the conversion of DNA into proteins that determine the function of the body's cells. Myotonic muscular dystrophy is the first example of a disease caused by toxic RNA.

In 1992, Mahadevan discovered the gene mutation that causes myotonic muscular dystrophy (type 1) as part of a research group in Canada. The mutation is an increased number of CTG repeats in a gene called DMPK. Everyone with myotonic muscular dystrophy has that mutation on chromosome 19, which is now part of a genetic, diagnostic test for myotonic dystrophy.

In their latest research, Mahadevan and c olleagues created a new type of mouse model with many extra copies of the CTG repeats, each attached to DNA for a protein that glows green under a microscope. They also integrated an "on switch" for MMD in the mice, activated by giving them doxycycline, an antibiotic, in their drinking water.

When mice began to produce many copies of RNA with CTG repeats, they developed the hallmarks of type 1 MMD within a few weeks, including an inability to relax muscles and heart rhythm abnormalities. When doxycycline was stopped, mice stopped producing toxic RNA and returned to normal, except in cases when the heart was severely damaged.

So far, however, Mahadevan and other scientists can't explain exactly what happens inside the cell to cause someone to get myotonic dystrophy. "The prevailing theory is that the RNA remains in the nucleus, rather than moving out of it, and proteins get stuck to the RNA and aren't able to do their job," Mahadevan said.

This toxic RNA in not found in every cell of body, Mahadevan said. Rather, it is produced in higher levels in muscle cells, in the heart and brain, in the lining of the intestines and in the lens and muscles of the eyes.


'"/>

Source:University of Virginia Health System


Related biology news :

1. Solution to Pollution: New Bacteria Eats Toxic Waste
2. Duke Chemists Isolating Individual Molecules Of Toxic Protein In Alzheimers, Parkinsons Disease
3. Same-Sex Mating Discovered in a Toxic Fungus
4. Toxic flood lifts lid on common urban pollution problem
5. Chemists create Superbowl molecule; May lead to better health
6. Key molecule in plant photo-protection identified
7. Inflammatory molecules released by pollen trigger allergies
8. Researchers discover molecule that causes secondary stroke
9. Yale researchers identify molecule for detecting parasitic infection in humans
10. Scientists identify molecule that regulates well-known tumor suppressor
11. Medical molecules designed to respond to visible light that can penetrate tissue
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/28/2016)... GOTHENBURG, Sweden , April 28, 2016 ... 1,491.2 M (139.9), up 966% compared with the first quarter of ... Operating profit totaled SEK 589.1 M (loss: 18.8) and the operating ... SEK 7.12 (loss: 0.32) Cash flow from operations was ... , The 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. ...
(Date:4/15/2016)... 15, 2016  A new partnership announced today ... underwriting decisions in a fraction of the time ... and high-value life insurance policies to consumers without ... With Force Diagnostics, rapid testing (A1C, Cotinine and ... (blood pressure, weight, pulse, BMI, and activity data) ...
(Date:3/31/2016)... 31, 2016   ... the "Company") LegacyXChange is excited to release ... soon to be launched online site for trading 100% ... ) will also provide potential shareholders a sense of ... to an industry that is notorious for fraud. The ...
Breaking Biology News(10 mins):
(Date:5/23/2016)... , May 23, 2016 - Leading ... 40% - Frontage Implement a Single Platform to Manage ... and Traceability Within the Bioanalytical lab Frontage Laboratories, a ... United States and China , has ... laboratory facilities. In addition to serving as the global electronic lab ...
(Date:5/23/2016)... ... May 23, 2016 , ... ... molecular nanotechnology, announced the winners for the 2015 Foresight Institute Feynman Prizes. ... given in two categories, one for experiment and the other for theory in ...
(Date:5/20/2016)... San Diego, CA (PRWEB) , ... May 20, 2016 , ... ... announce that 10 of its most experienced veterinary clients have treated over 100 of ... this cutting edge technology to provide the highest level of care for their patients. ...
(Date:5/20/2016)... ... ... Korean researchers say Manumycin A triggers apoptosis, or natural cell death, in ... disease. Surviving Mesothelioma has just posted an article on the new study. Click ... mesothelioma study on the fact the Manumycin A, a derivative of Streptomyces parvulus, is ...
Breaking Biology Technology: