Featured Research

from universities, journals, and other organizations

Transcription factor DksA polices the intersection of replication and transcription

Date:
May 13, 2010
Source:
Baylor College of Medicine
Summary:
DNA replication, the process by which a strand of DNA is copied during cell proliferation , and DNA transcription, the process by which the message in the DNA is translated into messenger RNA, involve the same "track" or DNA template. What happens when the two mechanisms are on the same track at the same time? Baylor College of Medicine researchers have identified the director -- the transcription factor DksA

DNA replication, the process by which a strand of DNA is copied during cell proliferation , and DNA transcription, the process by which the message in the DNA is translated into messenger RNA, involve the same "track" or DNA template. What happens when the two mechanisms are on the same track at the same time? Baylor College of Medicine researchers have identified the director -- the transcription factor DksA.

Related Articles


Dr. Jue D. (Jade) Wang, assistant professor of molecular and human genetics at Baylor College of Medicine, focuses her attention on replication -- the process by which a strand of DNA is copied during cell proliferation (growth and division).

Dr. Christophe Herman, also an assistant professor of molecular and human genetics at BCM, zeroes in on transcription -- the process by which the message in the DNA is translated into messenger RNA and ultimately the proteins that are workhorses of the cell.

Scientists in the two fields rarely communicate, but the two processes involve the same "track" or DNA template.

"What happens when two machines are on the same track but going in opposite directions?" said Wang. "These two processes are happening at the same time and use the same template."

Combining skills

The two laboratories combined their skills to answer that question and came up with a director -- the transcription factor DksA. A transcription factor is a protein that helps regulates expression (or the level) of gene activity.

A report on their work appears in the current issue of the journal Cell.

"We think this factor is one of the reason there are not more traffic jams," said Wang. "It is there to make sure that the traffic flows."

Director prevents conflict

Their experiments show that DksA acts on the process of transcription directly to prevent conflict between transcription and replication.

"The factor began our collaboration," said Herman. "We saw that it was regulating the process of transcription. It also tags along with RNA polymerase (the enzyme that prompts the process of making a strand of RNA from the DNA strand)."

When it sees the DNA polymerase (an enzyme critical to replication) come along, "it removes the RNA polymerase from the track," said Herman. That allows replication to take place and prevents the two "machines" from colliding.

The two did their work in a form of Escherichia coli (E. coli), a bacterium often used as a model organism in the laboratory. When DksA was not present in the bacteria, the cell was unstable, prompting a DNA damage response from halted replication.

"Stress can promote endogenous DNA damage," said Herman. Starvation is one method of such stress, he said. When DksA is present, it prevents disruption of replication and maintains the integrity of the DNA.

Findings raise questions

Previously, it was thought that the DNA polymerase simply knocked the RNA polymerase out of the way, said Herman.

"That is not the case. You need to have specific factors to remove the RNA polymerase," he said.

The findings raise as many questions as they answer, said Wang. Does the factor work before or after the enzymes collide?

"We don't know the mechanism yet," she said.

Others who took part in this work include Ashley K. Tehranchi, Matthew D. Blankschien, Yan Zhang, Jennifer Halliday, Anjana Srivatsan and Jia Peng, all of BCM.

Funding for this work came from a Human Frontier Young Investigator Grant, the Robert A. Welch Foundation and the National Institutes of Health.


Story Source:

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


Journal Reference:

  1. Ashley K. Tehranchi, Matthew D. Blankschien, Yan Zhang, Jennifer A. Halliday, Anjana Srivatsan, Jia Peng, Christophe Herman, Jue D. Wang. The Transcription Factor DksA Prevents Conflicts between DNA Replication and Transcription Machinery. Cell, 2010; 141 (4): 595 DOI: 10.1016/j.cell.2010.03.036

Cite This Page:

Baylor College of Medicine. "Transcription factor DksA polices the intersection of replication and transcription." ScienceDaily. ScienceDaily, 13 May 2010. <www.sciencedaily.com/releases/2010/05/100513123706.htm>.
Baylor College of Medicine. (2010, May 13). Transcription factor DksA polices the intersection of replication and transcription. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2010/05/100513123706.htm
Baylor College of Medicine. "Transcription factor DksA polices the intersection of replication and transcription." ScienceDaily. www.sciencedaily.com/releases/2010/05/100513123706.htm (accessed October 30, 2014).

Share This



More Health & Medicine News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Mind-Controlled Prosthetic Arm Restores Amputee Dexterity

Reuters - Innovations Video Online (Oct. 29, 2014) A Swedish amputee who became the first person to ever receive a brain controlled prosthetic arm is able to manipulate and handle delicate objects with an unprecedented level of dexterity. The device is connected directly to his bone, nerves and muscles, giving him the ability to control it with his thoughts. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Google To Use Nanoparticles, Wearables To Detect Disease

Google To Use Nanoparticles, Wearables To Detect Disease

Newsy (Oct. 29, 2014) Google X wants to improve modern medicine with nanoparticles and a wearable device. It's all an attempt to tackle disease detection and prevention. Video provided by Newsy
Powered by NewsLook.com
Can Drinking Milk Lead To Early Death?

Can Drinking Milk Lead To Early Death?

Newsy (Oct. 29, 2014) Researchers in Sweden released a study showing heavy milk drinkers face an increased mortality risk from a variety of causes. Video provided by Newsy
Powered by NewsLook.com
Obama: The US Will Not 'run and Hide' From Ebola

Obama: The US Will Not 'run and Hide' From Ebola

AP (Oct. 29, 2014) Surrounded by health care workers in the White House East Room, President Barack Obama said the U.S. will likely see additional Ebola cases in the weeks ahead. But he said the nation can't seal itself off in the fight against the disease. (Oct. 29) 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