Featured Research

from universities, journals, and other organizations

New knowledge about muscular dystrophy uncovered

Date:
May 5, 2014
Source:
Aarhus University
Summary:
A previously unknown function of a cellular enzyme that can disperse toxic aggregates in the cells of patients with muscular dystrophy has been uncovered by researchers. The most common form of muscular dystrophy among adults is dystrophia myotonica type 1 (DM1), where approximately 1 in every 8000 is affected by the disease. The severity of the disease varies from mild forms to severe congenital forms. It is dominantly inherited and accumulates through generations, gaining increased severity and lowered age of onset.

The research team behind the new results of muscular dystrophy (from left): Thomas G. Jensen, Rune Thomsen, Olof Pettersson, Lars Aagaard og Christian Damgaard (Diana Andrejeva is missing in the photo).
Credit: Lisbeth Heilesen

The most common form of muscular dystrophy among adults is dystrophia myotonica type 1 (DM1), where approximately 1 in every 8000 is affected by the disease. The severity of the disease varies from mild forms to severe congenital forms. It is dominantly inherited and accumulates through generations, gaining increased severity and lowered age of onset. DM1 is characterized by accumulating toxic aggregates of ribonucleic acids (RNA) from a specific mutated gene.

When this RNA, which contains thousands of CUG nucleotide repeats, builds up in the cell, it attracts several cellular proteins, including muscleblind 1 (MBNL1). This binding inhibits the normal function of MBNL1, which means that the cellular level of a number of specific proteins becomes deregulated and the disease develops.

Enzyme characterization in muscular dystrophy patients

The researchers work at the Department of Molecular Biology and Genetics and the Department of Biomedicine, Aarhus University, where they characterized an enzyme called DDX6, found in both normal cells and cells from muscular dystrophy patients.

The enzyme constantly tries to disperse the toxic aggregates and release MBNL1 in cells from muscular dystrophy patients, which means that the protein can carry out its normal function. The enzyme is found in many different cell types, where it performs a number of vital functions. The researchers showed that an artificial increase in the level of DDX6 in muscular dystrophy cells reduces the number of RNA aggregates, while more are formed when DDX6 is removed from the cells.

DDX6 belongs to a class of enzymes called helicases, which can change RNA structure and also regulate the ability of proteins to bind RNA. By purifying DDX6 from human cells, the researchers succeeded in getting the enzyme to bind and carry out an enzymatic reaction outside the cell, thus changing the structure of the toxic RNA.

These results indicate that DDX6 has a direct impact on toxic RNA aggregation in cells from muscular dystrophy patients in addition to its normal functions.

It remains unlikely that DDX6 can be used directly in the treatment of muscular dystrophy, since the enzyme carries out a number of important processes in the cell, which could potentially become deregulated leading to other diseases. However, the results provide important insights into the basic mechanisms of the disease, and natural differences in enzyme levels in different types of cells (or individuals) could possibly explain observed tissue-specific differences in the development of the disease.


Story Source:

The above story is based on materials provided by Aarhus University. The original article was written by Lisbeth Heilesen. Note: Materials may be edited for content and length.


Journal Reference:

  1. O. J. Pettersson, L. Aagaard, D. Andrejeva, R. Thomsen, T. G. Jensen, C. K. Damgaard. DDX6 regulates sequestered nuclear CUG-expanded DMPK-mRNA in dystrophia myotonica type 1. Nucleic Acids Research, 2014; DOI: 10.1093/nar/gku352

Cite This Page:

Aarhus University. "New knowledge about muscular dystrophy uncovered." ScienceDaily. ScienceDaily, 5 May 2014. <www.sciencedaily.com/releases/2014/05/140505104355.htm>.
Aarhus University. (2014, May 5). New knowledge about muscular dystrophy uncovered. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2014/05/140505104355.htm
Aarhus University. "New knowledge about muscular dystrophy uncovered." ScienceDaily. www.sciencedaily.com/releases/2014/05/140505104355.htm (accessed August 20, 2014).

Share This




More Health & Medicine News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) — A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Raw: World's Oldest Man Lives in Japan

Raw: World's Oldest Man Lives in Japan

AP (Aug. 20, 2014) — A 111-year-old Japanese was certified as the world's oldest man by Guinness World Records on Wednesday. Sakari Momoi, a native of Fukushima in northern Japan, was given a certificate at a hospital in Tokyo. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) — A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Freetown a City on Edge

Ebola-Hit Sierra Leone's Freetown a City on Edge

AFP (Aug. 19, 2014) — Residents of Sierra Leone's capital voice their fears as the Ebola virus sweeps through west Africa. Duration: 00:56 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins