Featured Research

from universities, journals, and other organizations

A Protein Complex That Untangles DNA

Date:
July 16, 2006
Source:
Karolinska Institutet
Summary:
Every second, the cells constituting our bodies are replaced through cell division. Researchers at Karolinska Institutet have found a piece of the puzzle of how genetic information remains intact despite this continuous exchange of cells. Their results are presented in the latest issue of the scientific journal Molecular Cell.

Every second, the cells constituting our bodies are replaced through cell division. Researchers at Karolinska Institutet have found a piece of the puzzle of how genetic information remains intact despite this continuous exchange of cells. Their results are presented in the latest issue of the scientific journal Molecular Cell.

Related Articles


An adult human consists of about 50,000 billion cells, 1% of which die and are replaced by cell division every day. In order to ensure cell survival and controlled growth of these new cells, the genetic information, stored in DNA molecules, must first be correctly copied and then accurately distributed during cell division. Moreover, to fully ascertain that the new cells will contain the same genetic information as the parental cells, any damage to the DNA, which is organised into several chromosomes, must be repaired.

"A cancer cell often has chromosomal aberrations that can be linked to erroneous copying, separation, or repair of the DNA molecule. By learning about the normal mechanisms that maintain a stable genome we can gain a better position to understand what goes wrong in cancer", says Camilla Sj๖gren, who leads the research group.

Central to both chromosome repair and distribution during cell division are three related protein complexes.

"Quite a bit is known about two of these complexes. One of them, cohesin, keeps the DNA copies together such that they do not separate too early; while the other, condensin, makes the chromosomes more compact, making the separation easier", says Camilla Sj๖gren.

The research group has studied the third, less well understood, protein complex, known as the Smc5/6 complex. This protein complex was found to bind to locations on the DNA strand that the researchers had artificially damaged, suggesting that it is directly involved in the repair process. Moreover, the Smc5/6 complex also seems to be required for the disentanglement of undamaged chromosomes before cell division. If these tangles, which are a natural consequence of the DNA copying process, are left unresolved the chromosomes cannot be separated and sent to the two nascent daughter cells. Like in the repair process, the Smc5/6 complex appears to resolve these intertwines by direct interaction with the DNA molecules, but this process is differently regulated as compared to the function in repair.

"Evidence points to that the Smc5/6 complex work in two different pathways, one needed for repair and the other for untangling. We now aim to study how this works on a molecular level. This will bring us one step closer to the general goal – a summary of the many mechanisms that collaborate to maintain our genetic stability", says Camilla Sj๖gren.


Story Source:

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


Cite This Page:

Karolinska Institutet. "A Protein Complex That Untangles DNA." ScienceDaily. ScienceDaily, 16 July 2006. <www.sciencedaily.com/releases/2006/07/060716090339.htm>.
Karolinska Institutet. (2006, July 16). A Protein Complex That Untangles DNA. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2006/07/060716090339.htm
Karolinska Institutet. "A Protein Complex That Untangles DNA." ScienceDaily. www.sciencedaily.com/releases/2006/07/060716090339.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) — Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) — One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) — Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
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

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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