Featured Research

from universities, journals, and other organizations

Newly discovered ancestral enzyme facilitates DNA repair

Date:
November 20, 2013
Source:
Centro Nacional de Investigaciones Oncologicas (CNIO)
Summary:
Researchers have discovered how a new human enzyme, the protein PrimPol, is capable of recognizing DNA lesions and facilitate their repair during the DNA copying process, thus avoiding irreversible and lethal damage to the cells and, therefore, to the organism.

Every day, the human body produces new cells to regenerate tissues and repair those that have suffered injury. Each time this happens, the cells make copies of their DNA that they will pass on to the resulting daughter cells. This process of copying the DNA, also called replication, is very delicate, given that it can generate severe alterations in the DNA that are associated with malignant transformation or ageing.

Related Articles


Researchers from the Spanish National Cancer Research Centre (CNIO), led by Juan Méndez, head of the DNA Replication Group, together with Luis Blanco, from the Severo Ochoa Molecular Biology Centre (CBM-CSIC), have discovered how a new human enzyme, the protein PrimPol, is capable of recognising DNA lesions and facilitate their repair during the DNA copying process, thus avoiding irreversible and lethal damage to the cells and, therefore, to the organism.

The results are published in the online edition of the journal Nature Structural and Molecular Biology. This study represents the continuation of a prior study, published recently by the same researchers in the journal Molecular Cell, in which they described the existence and biochemical properties of the PrimPol enzyme.

The DNA that resides in the nucleus of cells is the carrier of the genes, the instruction manuals that dictate how the cell works. "DNA structure is very stable, except during replication which normally takes approximately eight hours in human cells; during that period it becomes more fragile and can break," says Méndez. These eight hours are therefore critical for cells: they have to ensure the fidelity of copying DNA, and if errors are found or the DNA is damaged, they have to repair them as efficiently as possible.

Avoiding Collapse

DNA polymerases are the enzymes responsible for synthesising new DNA. "When a DNA polymerase finds an obstacle in the DNA [a chemical alteration introduced by solar ultraviolet radiation, for example], the copy is interrupted and the process stops until the error is repaired. This interruption can cause breaks in the DNA, translocations of fragments from some chromosomes to others, and even cause cell death or malignant transformation," says Méndez.

The research carried out by CNIO and CSIC demonstrates that the PrimPol enzyme prevents the copying process from being interrupted when there is damage: it recognises lesions and skips over them, and they are repaired when the copy is finished.

In evolutionary terms, PrimPol is a very old enzyme, and similar proteins have been found in archaebacteria, one of the first life forms that inhabited the Earth. "Millions of years ago, life conditions were more difficult [high salinity, extreme temperatures, etc.], so PrimPol has probably adapted to synthesising DNA in these conditions that encourage damage," says Méndez, adding that: "in exchange, these primitive DNA polymerases are less exact than the more evolved copying systems and can introduce mutations."

The scientists anticipate that this increase in mutations could have played a key role in the evolution of genomes, as well as having an impact on the ageing of cells and the development of cancer. Having identified and characterised this new protein in human beings, the researchers tell us that they are already studying its role in disease development.


Story Source:

The above story is based on materials provided by Centro Nacional de Investigaciones Oncologicas (CNIO). Note: Materials may be edited for content and length.


Journal Reference:

  1. Silvana Mourón, Sara Rodriguez-Acebes, María I Martínez-Jiménez, Sara García-Gómez, Sandra Chocrón, Luis Blanco, Juan Méndez. Repriming of DNA synthesis at stalled replication forks by human PrimPol. Nature Structural & Molecular Biology, 2013; DOI: 10.1038/nsmb.2719

Cite This Page:

Centro Nacional de Investigaciones Oncologicas (CNIO). "Newly discovered ancestral enzyme facilitates DNA repair." ScienceDaily. ScienceDaily, 20 November 2013. <www.sciencedaily.com/releases/2013/11/131120100623.htm>.
Centro Nacional de Investigaciones Oncologicas (CNIO). (2013, November 20). Newly discovered ancestral enzyme facilitates DNA repair. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2013/11/131120100623.htm
Centro Nacional de Investigaciones Oncologicas (CNIO). "Newly discovered ancestral enzyme facilitates DNA repair." ScienceDaily. www.sciencedaily.com/releases/2013/11/131120100623.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) — IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) — A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) — The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) — An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) 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:

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