Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biologists describe mechanism promoting multiple DNA mutations

31.07.2014

Research could lead to development of new cancer therapies

DNA mutations—long known to fuel cancer as well as evolutionary changes in a living organism—had been thought to be rare events that occur randomly throughout the genome.

However, recent studies have shown that cancer development frequently involves the formation of multiple mutations that arise simultaneously and in close proximity to each other. These groups of clustered mutations are frequently found in regions where chromosomal rearrangements take place.

The discovery, published in the journal Cell Reports, may one day lead to new cancer therapies, according to a University of Iowa biologist and her colleagues, and a group of researchers from the National Institute of Environmental Health Sciences led by Senior Associate Scientist Dmitry Gordenin.

The formation of clustered mutations may result from the process of DNA repair.

Anna Malkova, associate professor of biology in the UI College of Liberal Arts and Sciences, notes that the DNA repair pathway, known as break-induced replication (BIR), can promote clusters of DNA mutations.

“Previously, we have shown that double-strand DNA breaks, which can result from oxidation, ionizing radiation and replication errors, can be repaired by BIR,” says Malkova.

“During BIR, one broken DNA end is paired with an identical DNA sequence on another chromosome and initiates an unusual type of replication, which proceeds as a migrating bubble and is associated with the accumulation of large amounts of single-strand DNA,” she says.

In the Cell Reports study, researchers subjected yeast cells undergoing BIR to alkylating (cancer cell-killing agents) damage. “We found that the single-stranded DNA regions that accumulate during BIR are susceptible to damage that leads to the formation of mutation clusters,” explains Cynthia Sakofsky, postdoctoral fellow at the UI and one of two co-first authors on the paper. “These clusters are similar to those found in human cancer,” she says.

Importantly, say the researchers, the paper provides a mechanism to potentially explain how genetic changes form in human cancers. Thus, it will be critical for future research to determine whether BIR can form clustered mutations that lead to cancer in humans. If this turns out to be true, it may lead to the discovery of new targets for developing therapies against human cancers.

In addition to Malkova, Gordenin and Sakofsky, co-authors of the paper are: Steven A. Roberts, co-first author, and Michael A. Resnick, both of the National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina; and Ewa Malc and Piotr A. Mieczkowski, both of the Department of Genetics, Lineberger Comprehensive Cancer Center and Carolina Center for Genome Sciences, University of North Carolina, Chapel Hill, North Carolina.

The paper, titled “Break-Induced Replication Is a Source of Mutation Clusters Underlying Kataegis,” was published in the May 29 issue of Cell Reports.

The research was funded by NIH grants R01GM084242 (to A.M.) and 5R01GM052319-17 (to P.A.M.) and by the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences (project ES065073, to M.A.R). S.A.R. was supported by NIH Pathway to Independence Award K99ES022633-01.

Contacts

Anna Malkova, Department of Biology, 319-384-1285
Gary Galluzzo, Strategic Communications, 319-384-0009

Gary Galluzzo | Eurek Alert!
Further information:
http://now.uiowa.edu/2014/07/biologists-describe-mechanism-promoting-multiple-dna-mutations

Further reports about: Cell DNA Environmental clusters damage mechanism mutations repair replication

More articles from Life Sciences:

nachricht Nerves control the body’s bacterial community
26.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Ageless ears? Elderly barn owls do not become hard of hearing
26.09.2017 | Carl von Ossietzky-Universität Oldenburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The fastest light-driven current source

Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.

Graphene is up to the job

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Nerves control the body’s bacterial community

26.09.2017 | Life Sciences

Four elements make 2-D optical platform

26.09.2017 | Physics and Astronomy

Goodbye, login. Hello, heart scan

26.09.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>