Featured Research

from universities, journals, and other organizations

New Mechanism In Development Of Severe Inherited Disease Discovered

Date:
September 5, 2007
Source:
Helmholtz Association
Summary:
Scientists have shown that the genetic defect that causes Cockayne Syndrome affects a key function of the cell - the transcription of genes coding for ribosomal RNA. Cockayne Syndrome is a recessively inherited disorder that belongs to a group of diseases in which defects in one of the numerous DNA repair systems lead to non-functioning proteins and, thus, to severe health impairments. These disorders also include, for example, Xeroderma pigmentosum and a type of hereditary bowel cancer.

Scientists of the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) have shown that the genetic defect that causes Cockayne Syndrome affects a key function of the cell - the transcription of genes coding for ribosomal RNA.

Cockayne Syndrome is a recessively inherited disorder that belongs to a group of diseases in which defects in one of the numerous DNA repair systems lead to non-functioning proteins and, thus, to severe health impairments. These disorders also include, for example, Xeroderma pigmentosum and a type of hereditary bowel cancer.

However, symptoms of Cockayne Syndrome, which is a very rare disease, are particularly severe, including dwarfism, mental retardation, hearing and vision impairments; affected individuals have a characteristically formed small head, they age prematurely and die younger. The scale of these defects suggested that a dysfunctional DNA repair mechanism alone cannot be responsible for this whole range of impairments.

Cockayne Syndrome is characterized by a defect in the CSB protein, which is the main component of a particular DNA repair system. Research results of several working groups had already suggested that CSB is additionally involved in transcription, i.e. the conversion of DNA to RNA. However, the exact mechanism had remained unknown.

In each cell, various RNA types are responsible for specific tasks. Thus, the so-called rRNA is a key component of the ribosomes, the protein factories of the cell. A research group headed by Professor Dr. Ingrid Grummt of the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) has now shown that CSB is pivotal in the production of rRNA molecules.

A basic prerequisite for the conversion of DNA to RNA is the accessibility of genes, which are normally tightly packed in the chromosome. Only if the genes are accessible can the enzyme RNA polymerase go about its work and synthesize new RNA molecules according to the DNA code. This is where CBS comes into play: It functions as an adapter between polymerase and the G9a protein, which acts like an icebreaker - making specific regions of the genetic material accessible for polymerase by chemically modifying the protein scaffold of the chromosome.

Without functioning CBS, the binding of polymerase I and G9a fails and the genes coding for rRNAs remain inaccessible for polymerase. The lack of rRNAs eventually leads to a standstill of protein synthesis in the cell - the most dramatic of imaginable consequences for an organism. This newly discovered function of CBS explains why a defect of this enzyme has such severe effects on the organism.

Xuejun Yuan, Weiijun Feng, Axel Imhof, Ingrid Grummt and Yonggang Zhou: Activation of RNA polymerase I transcription by Cockayne Syndrome group B (CSB) protein and histone methyltransferase G9a. Molecular Cell, August 19, 2007

The task of the Deutsches Krebsforschungszentrum in Heidelberg (German Cancer Research Center, DKFZ) is to systematically investigate the mechanisms of cancer development and to identify cancer risk factors. The findings resulting from basic research are expected to lead to new approaches in the prevention, diagnosis, and treatment of cancer. Funding is provided by the Federal Ministry of Education and Research (BMBF; 90 percent) and by the State of Baden-Wuerttemberg (10 percent). The German Cancer Research Center is a member of the Helmholtz Association of National Research Centers (Helmholtz-Gemeinschaft Deutscher Forschungszentren e.V.).


Story Source:

The above story is based on materials provided by Helmholtz Association. Note: Materials may be edited for content and length.


Cite This Page:

Helmholtz Association. "New Mechanism In Development Of Severe Inherited Disease Discovered." ScienceDaily. ScienceDaily, 5 September 2007. <www.sciencedaily.com/releases/2007/08/070831201855.htm>.
Helmholtz Association. (2007, September 5). New Mechanism In Development Of Severe Inherited Disease Discovered. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2007/08/070831201855.htm
Helmholtz Association. "New Mechanism In Development Of Severe Inherited Disease Discovered." ScienceDaily. www.sciencedaily.com/releases/2007/08/070831201855.htm (accessed October 2, 2014).

Share This



More Health & Medicine News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com
Insertable Cardiac Monitor

Insertable Cardiac Monitor

Ivanhoe (Oct. 1, 2014) A heart monitor the size of a paperclip that can save your life. The “Reveal Linq” allows a doctor to monitor patients with A-Fib on a continuous basis for up to 3 years! Video provided by Ivanhoe
Powered by NewsLook.com
Attacking Superbugs

Attacking Superbugs

Ivanhoe (Oct. 1, 2014) Two weapons hospitals can use to attack superbugs. Scientists in Ireland created a new gel resistant to superbugs, and a robot that can disinfect a room in minutes. Video provided by Ivanhoe
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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