Navigation Links
Stopgap DNA repair needs a second step
Date:5/4/2009

One can have a dream, two can make that dream so real, goes a popular song. Now a Weizmann Institute study has revealed that it takes two to perform an essential form of DNA repair.

Prof. Zvi Livneh of the Weizmann Institute's Biological Chemistry Department has been studying DNA repair for some two decades: 'Considering that the DNA of each cell is damaged about 20,000 times a day by radiation, pollutants and harmful chemicals produced within the body, it's obvious that without effective DNA repair, life as we know it could not exist. Most types of damage result in individual mutations genetic 'spelling mistakes' that are corrected by precise, error-free repair enzymes. Sometimes, however, damage results in more than a mere spelling mistake; it can cause gaps in the DNA, which prevent the DNA molecule from being copied when the cell divides, much like an ink blot or a hole on a book page interferes with reading. So dangerous are these gaps that the cell resorts to a sloppy but efficient repair technique to avoid them: It fills in the missing DNA in an inaccurate fashion. Such repair can save the cell from dying, but it comes at a price: this error-prone mechanism, discovered at the Weizmann Institute and elsewhere about a decade ago, is a major source of mutations.'

In a recent study he conducted with graduate students Sigal Shachar and Omer Ziv, as well as researchers from the US and Germany, Livneh revealed how the error-prone repair works. The team found that such repair proceeds in two steps and requires two types of enzymes, belonging to the family of enzymes called DNA polymerases, which synthesize DNA. First, one repair enzyme, 'the inserter,' does its best to fit in a genetic 'letter' into the gap, opposite the damaged site in the DNA molecule; several enzymes can perform this initial step, which often results in the insertion of an incorrect genetic letter. Next, another enzyme, 'the extender,' helps to restore regular copying of DNA by attaching additional DNA letters after the damaged site; only one repair enzyme is capable of performing this vital second step. These findings were published recently in the EMBO Journal.

Understanding how this major form of DNA repair works can have significant clinical implications. Since defects in this process increase the risk of cancer, clarifying its nuts and bolts might one day make it possible to enhance it in people whose natural DNA repair is deficient. In addition, manipulating this mechanism can improve the effectiveness of cancer drugs. Cancer cells can resist chemotherapy by exploiting their natural repair mechanisms, and blocking these mechanisms may help overcome this resistance, leading to a targeted destruction of the cancerous tumor.


'/>"/>

Contact: Yivsam Azgad
news@weizmann.ac.il
972-893-43856
Weizmann Institute of Science
Source:Eurekalert

Related medicine news :

1. Stem Cells Repair Damaged Corneas in Mice
2. Molecule prompts damaged heart cells to repair themselves after a heart attack
3. MEDRAD Multi Vendor Service Launches TotalRepair(SM) on Select Ultrasound Probes
4. Penn researchers identify new protein important in breast cancer genes role in DNA repair
5. Long-term outlook good for rotator cuff repairs
6. Latin American Market for Hernia Repair Devices Achieving Double-Digit Growth
7. Using a Balloon to Repair a Broken Back
8. Mount Sinai first in US to implant FDA-cleared ring for mitral valve repair
9. Quick Orthopedic Repair Can Save Young Shoulders
10. Nurses to Congress: Expanding Medicare Could Reverse Job Losses, and Repair Our Broken Healthcare System and Safety Net
11. Brooke Shields and the Makers of COPPERTONE(R) Join Together to Launch COPPERTONE(R) NutraShield(TM) - New Sunscreen Contains Antioxidants That Promote Natural Skin Repair
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/24/2017)... ... 24, 2017 , ... Accordant Technology, a trusted IT solutions ... an analytics-first approach, layered with machine learning, that provides real-time visibility into the ... cloud to the edge. Through the new partnership, customers get the real-time situational ...
(Date:5/24/2017)... ... May 24, 2017 , ... Fiberstar, Inc., ... the food and beverage industry offers Citri-Fi®, a natural citrus fiber, to improve ... decision process. As a result, labels need to deliver simple, transparent and clear ...
(Date:5/23/2017)... , ... May 23, 2017 , ... Allegheny Health ... open The Alexis Joy D’Achille Center for Women’s Behavioral Health at West Penn ... in western Pennsylvania for women suffering from pregnancy-related depression. Construction of the Center ...
(Date:5/23/2017)... , ... May 23, 2017 , ... ... body for exercise professionals, is pleased to announce the organization’s Certified Strength Coach ... The NCSF Certified Strength Coach (CSC) program validates the competency of qualified candidates ...
(Date:5/23/2017)... York (PRWEB) , ... May 23, 2017 , ... ... LifeLabs, a leading equipment provider in the modern ART laboratory, to provide hands-on ... in Ft. Lauderdale, Florida. , NextGen LifeLabs, a MedTech Group Purchasing vendor ...
Breaking Medicine News(10 mins):
(Date:5/18/2017)...  Bayer announced today that the latest research from ... the 53 rd Annual Meeting of the American ... in Chicago . ... liver and thyroid cancers, as well as lymphomas, and ... trial of copanlisib in patients with relapsed or refractory ...
(Date:5/11/2017)... , May 11, 2017  Thornhill Research ... has been awarded an $8,049,024 USD five-year, firm-fixed-priced, ... through the Canadian Commercial Corporation (CCC) ( ... Anesthesia Systems to administer general anesthesia to patients ... "The US Marine Corps have been ...
(Date:5/10/2017)... May 10, 2017 Radiology has become the ... costs have also spiraled to the number one ranking ... radiology than ever before as the most complete and ... patient with lower back pain an MRI may confirm ... for pain, resulting in entirely different treatment protocols.  In ...
Breaking Medicine Technology: