Navigation Links
Dual systems key to keeping chromosomes intact
Date:3/7/2013

USC scientists have discovered how two different structural apparatuses collaborate to protect repetitive DNA when it is at its most vulnerable while it is being unzipped for replication.

The centromerethe center of the "X" shape of a chromosomecontains repeated DNA sequences that are epigenetically coded to attract so-called heterochromatin proteins. This protects the structure to ensure that the chromosomes separate properly. If the heterochromatin is lost (due to mutations in the cell), the repetitive DNA becomes vulnerable to rearrangements and recombination. This particularly true during DNA replication, when the DNA is transiently unwound to be copied.

If there are also defects in replication fork proteins that cause this process to be delayed or inefficient, the rearrangements are dramatically increased. This "genome instability" can lead to loss of genetic information or genetic changes that can lead to cell death or cause cancer.

Susan Forsburg, who led the USC team that conducted the research, used yeast cells to show that simultaneously disrupting both heterochromatin and replication fork proteins caused significant increases in abnormal chromosomes, and in some cases, cell death.

"The insight here is really understanding the mechanism of how these different mutants create a lethal collaboration," said Forburg, a professor of molecular biology at the USC Dornsife College of Letters, Arts and Sciences. "Importantly, all the genes we study have human equivalentsand mutations of some of these are already linked to cancer."

The research appears online in Cell Reports on March 7. Forsburg worked with Pao-Chen Li, formerly a graduate student at USC and now a post-doctoral researcher at UCSF; as well as Ruben C. Petreaca, Amanda Jensen, Ji-Ping Yuan and Marc D. Green, all from USC.

"We already knew epigenetic modifications change gene expression in cancer," Forsburg said. "Now we see a synergistic effect between the structural role of epigenetic modification that creates heterocrhomatin, and replication fork stability."

The next step will be to identify additional components that show this same synergistic effect and to determine what other functions act with heterochromatin to preserve genome stability.


'/>"/>

Contact: Robert Perkins
perkinsr@usc.edu
213-740-9226
University of Southern California
Source:Eurekalert

Related medicine news :

1. Is it time for regional cardiovascular emergency care systems across the US?
2. Program to coordinate regional systems to speed heart attack care
3. A systems approach to preventing obesity in early life
4. Researchers call for obesity prevention efforts to focus on community-wide systems
5. Cancers with disorganized traffic systems more difficult to treat: U of A research
6. Fitness 4 Home Online Introduces the Saber Strength Adjustable Weight Systems
7. Study looks at efforts to improve local food systems through policy
8. Systems biologist receives $2.5 million Pioneer Award for genome research
9. Students win $100K for 3-D printer to turn waste plastic into composting toilets, rainwater systems
10. In financial ecosystems, big banks trample economic habitats and spread fiscal disease
11. UCAN Selects Defran Systems to Support its Wide Range of Youth and Family Programs
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2017)... ... May 26, 2017 , ... Rob Lowe acts as ... production of the series is on hiking in American. Viewers can reconnect with America ... great benefits of hiking. , Many consumers have looked for an inventive new place ...
(Date:5/26/2017)... ... May 26, 2017 , ... “THE FLINTHILLS FAMILY-Our Journey to the Cross”: the personal journey of ... Cross” is the creation of published authors, Bob and Margaret Massey. Bob Massey is ... is "panther quick and leather tough." His love for others is apparent in all ...
(Date:5/26/2017)... ... ... Jack: Against All Odds”: the story of Coach Cactus Jack and the impact he ... creation of published author, Walter Hubbard, a retired wildlife and fisheries biologist and pharmacy ... Walter and Jane have three adult children and a granddaughter. Walter and ...
(Date:5/24/2017)... ... May 24, 2017 , ... In ... choosing the most appropriate instruments for research and understanding the basic principles that ... webinar will focus on innovations in stereo microscopy for brightfield and fluorescence typically ...
(Date:5/24/2017)... California (PRWEB) , ... May 24, 2017 , ... ... through innovative medical image management and interpretation, has received U.S. Food and Drug ... , Nucleus.io is a web-based, scalable and secure cloud platform for medical image ...
Breaking Medicine News(10 mins):
(Date:5/15/2017)... Inc., a privately-held CNS pharmaceutical company based in ... disease (PD), has enrolled the first patient in the RASMET ... study involving patients with PD and taking place at 12 ... period. The first stage is open label and involves single ... Denver , Boca Raton ...
(Date:5/10/2017)... Global Health Intelligence (GHI), the leading healthcare data analytics ... 2017 ranking of the Best-Equipped Hospitals in Latin America ... GHI,s hospitals database for Latin America , which is ... database covers 86% of the hospitals in Latin ... each institution in key areas such as beds, medical specialties, ...
(Date:5/9/2017)... -- Zimmer Biomet Holdings, Inc. (NYSE and SIX: ZBH), ... has earned a spot on Forbes, "America,s ... ranked among 500 U.S. employers as well as in ... Services. The annual Forbes rankings ... of over 30,000 employees across 25 industries. The survey ...
Breaking Medicine Technology: