Featured Research

from universities, journals, and other organizations

Detailed image shows how genomes are copied

Date:
December 1, 2013
Source:
Ume universitet
Summary:
For the first time, researchers have succeeded in showing how the DNA polymerase epsilon enzyme builds new genomes. The detailed image produced by these researchers shows how mutations that can contribute to the development of colorectal cancer and cervical cancer lead to changes in the structure of the protein.

DNA polymeras epsilon.
Credit: Ume University

For the first time, researchers at Ume University have succeeded in showing how the DNA polymerase epsilon enzyme builds new genomes. The detailed image produced by these researchers shows how mutations that can contribute to the development of colorectal cancer and cervical cancer lead to changes in the structure of the protein. This study will be published in the journal Nature Structural and Molecular Biology.

Genomes are built from pairs of long strands of DNA. In previous collaborations with American researchers, Ume University scientists have shown that DNA polymerase epsilon is one of the three enzymes that build DNA strands in all higher-level organisms from yeast to humans. When the DNA of an organism's genome is copied, DNA polymerase epsilon is responsible for building about half of the DNA. This process occurs quickly and with very high accuracy to avoid producing mutations that can be detrimental to the cell and to the organism as a whole.

To understand on a molecular level how DNA polymerase epsilon builds new DNA so quickly and accurately, researchers at Ume University have used X-ray crystallography techniques to produce a highly detailed picture of the protein caught in the act of building a new piece of DNA. They discovered that DNA polymerase epsilon has a unique protein structure -- a domain that has never been seen in any other polymerase. This new domain suggests that DNA polymerase epsilon has developed a unique way of holding on to the DNA that it is copying without falling off and having to start over again.

The researchers performed further experiments to confirm their new model and showed that the new domain (that they have called the P-domain) is, indeed, critically important for the protein's ability to build long strands of DNA without falling off. This is an important property of DNA polymerase epsilon that allows it to fulfil its role in copying DNA and reproducing the genome as a cell divides.

The human genome has now been mapped. Today there are large on-going international studies in which the DNA of tumor cells and of families with hereditary conditions are being sequenced to see if there are any special mutations that have caused the tumors to form or that have led to the hereditary conditions. As part of this work, a series of mutations within DNA polymerase epsilon have recently been discovered that can be directly linked to the development of colorectal and cervical cancers.

"The structure of the polymerase that we have solved makes it possible to see where these mutations lead to changes in the structure of DNA polymerase epsilon," says Erik Johansson, Professor at the Department of Medical Biochemistry and Biophysics, "This can help us to understand why a certain mutation contributes to the development of a certain cancer." Professor Johansson conducted the study in collaboration with others including Elisabeth Sauer-Eriksson, Professor at the Department of Chemistry.

The article describing this work will be published in the January edition of the journal Nature Structural and Molecular Biology. In addition, leading researchers in this field have also been invited to write a commentary on these discoveries in the journal's 'News and Views' section.


Story Source:

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


Journal Reference:

  1. Matthew Hogg, Pia Osterman, Gran O Bylund, Rais A Ganai, Else-Britt Lundstrm, A Elisabeth Sauer-Eriksson, Erik Johansson. Structural basis for processive DNA synthesis by yeast DNA polymerase ɛ. Nature Structural & Molecular Biology, 2013; DOI: 10.1038/nsmb.2712

Cite This Page:

Ume universitet. "Detailed image shows how genomes are copied." ScienceDaily. ScienceDaily, 1 December 2013. <www.sciencedaily.com/releases/2013/12/131201174328.htm>.
Ume universitet. (2013, December 1). Detailed image shows how genomes are copied. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2013/12/131201174328.htm
Ume universitet. "Detailed image shows how genomes are copied." ScienceDaily. www.sciencedaily.com/releases/2013/12/131201174328.htm (accessed September 20, 2014).

Share This



More Health & Medicine News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sierra Leone's Nationwide Ebola Curfew Underway

Sierra Leone's Nationwide Ebola Curfew Underway

Newsy (Sep. 20, 2014) Sierra Leone is locked down as aid workers and volunteers look for new cases of Ebola. Video provided by Newsy
Powered by NewsLook.com
Changes Found In Brain After One Dose Of Antidepressants

Changes Found In Brain After One Dose Of Antidepressants

Newsy (Sep. 19, 2014) A study suggest antidepressants can kick in much sooner than previously thought. Video provided by Newsy
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
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