Featured Research

from universities, journals, and other organizations

Study On Chromosome Ends May Aid Cancer Research

Date:
August 4, 2000
Source:
Princeton University
Summary:
A Princeton scientist has discovered a mechanism that cells use to control the length of their chromosome ends, a process that is thought to go awry in cancer. The finding, reported in the August 4 issue of Science by Professor of Molecular Biology Virginia Zakian and colleagues, may provide cancer researchers with clues for designing treatments.

PRINCETON, N.J. -- A Princeton scientist has discovered a mechanism that cells use to control the length of their chromosome ends, a process that is thought to go awry in cancer.

Related Articles


The finding, reported in the August 4 issue of Science by Professor of Molecular Biology Virginia Zakian and colleagues, may provide cancer researchers with clues for designing treatments.

Zakian found a naturally occurring protein that inhibits the activity of another protein, called telomerase, which replicates and lengthens the very ends of chromosomes. The protein, called Pif1p, acts directly on the chromosome ends, called telomeres, to keep the lengthening process in check, Zakian's research group reported.

Researchers have been studying telomerase with great intensity for the past 15 years because it appears to play a central role in the way cells age or become cancerous. Studies have shown that telomerase is present in 90 percent of cancer types, but is absent from most healthy cells. Cancer researchers have thus looked for ways to interfere with telomerase. Zakian's research suggests that mimicking or enhancing the action of Pif1p may be a good way to do so.

Telomerase builds structures called telomeres at the ends of chromosomes, like plastic caps at the ends of shoelaces. In normal conditions, telomeres shorten each time a cell divides, eventually exposing the genetic material and causing the cell to die. In cancer cells, however, telomerase keeps rebuilding the telomere caps, preventing the cell from undergoing its normal aging process.

In 1994, Zakian and collaborator Vincent Schulz reported that Pif1p keeps telomeres from lengthening. It remained unclear, however, how Pif1p accomplished that feat. There are many natural substances that could inhibit telomere lengthening in indirect ways,

Zakian said. The new paper shows that Pif1p acts on the telomerase pathway itself and interacts directly with telomeric DNA, a potentially attractive feature for drug developers.

One interesting aspect of Pif1p is that it is special type of enzyme, a helicase, that unwinds the double strands of DNA. Zakian's research team created a small mutation in the gene that encodes Pif1p so that the protein is produced normally yet lacks this unwinding ability. When telomerase-rich cells carried this mutated gene, Pif1p no longer worked and telomere lengthening progressed unchecked. Zakian believes that Pif1p may work by unzipping a temporary bond that forms between telomerase and the chromosome as telomeres are synthesized.

The experiments were done in baker's yeast cells, but Zakian said that telomere regulation has been so important throughout evolution that human cells employ many of the same mechanisms.

"These are very lowly organisms. This is what we use to bake bread," she said. "However, as we show in this paper, humans have a protein very similar to yeast Pif1p. It would be quite gratifying if it turned out that it also functions in a similar way in humans and could give us insights into human cancer."


Story Source:

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


Cite This Page:

Princeton University. "Study On Chromosome Ends May Aid Cancer Research." ScienceDaily. ScienceDaily, 4 August 2000. <www.sciencedaily.com/releases/2000/08/000804075602.htm>.
Princeton University. (2000, August 4). Study On Chromosome Ends May Aid Cancer Research. ScienceDaily. Retrieved March 31, 2015 from www.sciencedaily.com/releases/2000/08/000804075602.htm
Princeton University. "Study On Chromosome Ends May Aid Cancer Research." ScienceDaily. www.sciencedaily.com/releases/2000/08/000804075602.htm (accessed March 31, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Tuesday, March 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Solitair Device Aims to Takes Guesswork out of Sun Safety

Solitair Device Aims to Takes Guesswork out of Sun Safety

Reuters - Innovations Video Online (Mar. 31, 2015) — The Solitair device aims to take the confusion out of how much sunlight we should expose our skin to. Small enough to be worn as a tie or hair clip, it monitors the user&apos;s sun exposure by taking into account their skin pigment, location and schedule. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Soda, Salt and Sugar: The Next Generation of Taxes

Soda, Salt and Sugar: The Next Generation of Taxes

Washington Post (Mar. 30, 2015) — Denisa Livingston, a health advocate for the Dinι Community Advocacy Alliance, and the Post&apos;s Abby Phillip discuss efforts around the country to make unhealthy food choices hurt your wallet as much as your waistline. Video provided by Washington Post
Powered by NewsLook.com
UnitedHealth Buys Catamaran

UnitedHealth Buys Catamaran

Reuters - Business Video Online (Mar. 30, 2015) — The $12.8 billion merger will combine the U.S.&apos; third and fourth largest pharmacy benefit managers. Analysts say smaller PBMs could also merge. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
S. Leone in New Anti-Ebola Lockdown

S. Leone in New Anti-Ebola Lockdown

AFP (Mar. 28, 2015) — Sierra Leone imposed a three-day nationwide lockdown Friday for the second time in six months in a bid to prevent a resurgence of the deadly Ebola virus. Duration: 01:17 Video provided by AFP
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