Featured Research

from universities, journals, and other organizations

Clocking In And Out Of Gene Expression

Date:
June 15, 2007
Source:
Baylor College of Medicine
Summary:
A chemical signal acts as time clock in the expression of genes controlled by a master gene called a coactivator, according to a recent article.

Dr. Bert O'Malley
Credit: Baylor College of Medicine

A chemical signal acts as time clock in the expression of genes controlled by a master gene called a coactivator, said Baylor College of Medicine researchers in a report that recently appeared in the journal Cell.

"We have long known that our bodies live by a daily and monthly and even yearly clock and that cells have clocks as well," said Dr. Bert O'Malley, chair of molecular and cellular biology at BCM and senior author of this report. "We have actually taken this concept to the gene now and said that we are made up of 25,000 genes that have clocks too." Genes get expressed and carry out their functions through proteins, he said. Gene expression involves the machinery of the cell translating the gene's code into a protein that carries out function. This process has to have a beginning and an end.

"That sets the time clock," said O'Malley. "The question is, 'How is this done"'" The answer lies in coactivators -- master genes that turn other genes on and off.

"Inherent to the structure of these coactivators is a clock," he said. "But the clock needs to be set off." In studies of breast cancer cells, O'Malley and his colleagues showed how the clock works. Using steroid receptor coactivator-3 (SRC-3), they demonstrated that activation requires addition of a phosphate molecule to the protein at one spot and addition of an ubiquitin molecule at another point. Each time the message of the gene is transcribed into a protein, another ubiquitin molecule is chained on. Five ubiquitins in the chain and the protein is automatically destroyed.

"It's built-in self destruction," said O'Malley. "It prevents you from activating a potent factor in the cells that just keeps the clock running and the gene continuing to be expressed." In that scenario, the result could be cancer, too much growth or an abnormal function.

"It means there's a fixed length of time that the molecule can work. When it's activated, it's already preprogrammed to be destroyed. The clock's running and each time an ubiquitin is added, it is another tick of the clock." When the clock system fails, problems result.

"If you can't start the clock, you can't stop the clock. If you stop the clock before you should or if it is running too slow or too fast, it causes problems in the cells," he said.

Others who took part in this work included Drs. Ray-Chang Wu, Qin Feng and David M. Lonard, all of BCM's department of molecular and cellular biology.

Funding for this research came from the Welch Foundation and the National Institute of Child Health and Human Development and the Nuclear Receptor Signaling Atlas of the National Institute of Diabetes and Digestive and Kidney Diseases.


Story Source:

The above story is based on materials provided by Baylor College of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Baylor College of Medicine. "Clocking In And Out Of Gene Expression." ScienceDaily. ScienceDaily, 15 June 2007. <www.sciencedaily.com/releases/2007/06/070614121506.htm>.
Baylor College of Medicine. (2007, June 15). Clocking In And Out Of Gene Expression. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2007/06/070614121506.htm
Baylor College of Medicine. "Clocking In And Out Of Gene Expression." ScienceDaily. www.sciencedaily.com/releases/2007/06/070614121506.htm (accessed October 23, 2014).

Share This



More Plants & Animals News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
Goofy Dinosaur Blends Barney and Jar Jar Binks

Goofy Dinosaur Blends Barney and Jar Jar Binks

AP (Oct. 22, 2014) A collection of dinosaur bones reveal a creature that is far more weird and goofy-looking than scientists originally thought when they found just the arm bones nearly 50 years ago, according to a new report in the journal Nature. (Oct. 22) Video provided by AP
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) 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


Plants & Animals

Earth & Climate

Fossils & Ruins

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