Featured Research

from universities, journals, and other organizations

Molecule That Helps DNA Replicate May Make Good Target For Cancer Therapy

Date:
October 25, 2004
Source:
University Of Minnesota
Summary:
In order to divide, cells must first replicate their chromosomes. Cells use an array of proteins to accomplish the job, including a large enzyme complex that synthesizes new strands of DNA.

MINNEAPOLIS / ST. PAUL -- In order to divide, cells must first replicate their chromosomes. Cells use an array of proteins to accomplish the job, including a large enzyme complex that synthesizes new strands of DNA.

Related Articles


In a paper to be published Oct. 22 in the journal Molecular Cell, University of Minnesota researchers report that a particular protein, called minichromosome maintenance protein 10 (Mcm10), protects the enzyme from destruction and, like a molecular tugboat, escorts it to its "port"--the location on a chromosome where DNA replication will begin. Mcm10's versatility implies that it is indispensable for cell division. Therefore, drugs that target Mcm10 could be effective in stopping the uncontrolled cell division seen in cancerous tumors.

The work grew out of a desire to learn the identity of the "tugboat," said Anja Bielinsky, an assistant professor of biochemistry, molecular biology and biophysics, in whose laboratory the work was performed. The first author on the paper is Robin Ricke, a graduate student. The two scientists worked with baker's yeast, an organism often used to study basic biological mechanisms.

First, a little background on how DNA replicates itself: Before DNA replication can begin, the two strands in the DNA double helix must be unwound. Next, multiple molecules of a certain protein attach to the strands to keep them from spontaneously sticking together again. Only then can the star of the show--DNA polymerase alpha, the enzyme complex that synthesizes new DNA strands--be escorted to the specific sites on the DNA strands where it can attach and go to work.

"The big question was, How is polymerase alpha recruited to the first site?" said Bielinsky. "We found that Mcm10 brings the DNA polymerase alpha complex to the chromosomal sites where replication originates. It does this by attaching to the protein that keeps the two DNA strands from reconnecting. But what came as a complete surprise was that Mcm10 also stabilizes the polymerase alpha complex. In cells lacking Mcm10, the catalytic subunit of the complex--the part that attaches to DNA--was degraded so it could not attach." If the complex cannot attach to DNA, cell division is stopped cold.

The proteins that bring about DNA replication have been highly conserved during evolution; that is, the proteins are virtually identical whether the organism is yeast, an invertebrate or a human. Therefore, whatever is learned from yeast--which are much easier to work with than are human cells--is likely applicable to humans, Bielinsky said. Among the next steps for her lab is to find exactly how Mcm10 interacts with the polymerase alpha complex, because disrupting this interaction in a cancer cell might prevent it from multiplying. Also, the researchers want to know what it is in the cell that causes the degradation of the polymerase alpha complex when no Mcm10 is around to protect it. Bielinsky and her group are now beginning to work with chicken blood cells to confirm that Mcm10 works the same way in vertebrates as in yeast.

The work was supported by the Leukemia and Lymphoma Society and the American Cancer Society.


Story Source:

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


Cite This Page:

University Of Minnesota. "Molecule That Helps DNA Replicate May Make Good Target For Cancer Therapy." ScienceDaily. ScienceDaily, 25 October 2004. <www.sciencedaily.com/releases/2004/10/041022110506.htm>.
University Of Minnesota. (2004, October 25). Molecule That Helps DNA Replicate May Make Good Target For Cancer Therapy. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2004/10/041022110506.htm
University Of Minnesota. "Molecule That Helps DNA Replicate May Make Good Target For Cancer Therapy." ScienceDaily. www.sciencedaily.com/releases/2004/10/041022110506.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

UN: Up to One Million Facing Hunger in Ebola-Hit Countries

UN: Up to One Million Facing Hunger in Ebola-Hit Countries

AFP (Dec. 17, 2014) Border closures, quarantines and crop losses in West African nations battling the Ebola virus could lead to as many as one million people going hungry, UN food agencies said on Wednesday. Duration: 00:52 Video provided by AFP
Powered by NewsLook.com
When You Lose Weight, This Is Where The Fat Goes

When You Lose Weight, This Is Where The Fat Goes

Newsy (Dec. 17, 2014) Can fat disappear into thin air? New research finds that during weight loss, over 80 percent of a person's fat molecules escape through the lungs. Video provided by Newsy
Powered by NewsLook.com
Why Your Boss Should Let You Sleep In

Why Your Boss Should Let You Sleep In

Newsy (Dec. 17, 2014) According to research out of the University of Pennsylvania, waking up for work is the biggest factor that causes Americans to lose sleep. Video provided by Newsy
Powered by NewsLook.com
Flu Outbreak Closing Schools in Ohio

Flu Outbreak Closing Schools in Ohio

AP (Dec. 17, 2014) A wave of flu illnesses has forced some Ohio schools to shut down over the past week. State officials confirmed one pediatric flu-related death, a 15-year-old girl in southern Ohio. (Dec. 17) 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