Featured Research

from universities, journals, and other organizations

Researchers identify the source of 'noise' in HIV

Date:
April 20, 2010
Source:
Cell Press
Summary:
New research identifies a molecular mechanism that the human immunodeficiency virus (HIV) appears to utilize for generating random fluctuations called "noise" in its gene expression. The study pinpoints the likely source of HIV gene-expression noise and provides intriguing insight into the role of this noise in driving HIV's fate decision between active replication and latency.

New research identifies a molecular mechanism that the human immunodeficiency virus (HIV) appears to utilize for generating random fluctuations called "noise" in its gene expression. The study, published by Cell Press in the April 20th issue of the Biophysical Journal, pinpoints the likely source of HIV gene-expression noise and provides intriguing insight into the role of this noise in driving HIV's fate decision between active replication and latency.

Related Articles


After infecting a human cell, HIV integrates into the genome and typically begins to actively replicate. However, the virus can also enter a long-lived latent state, which remains the greatest barrier to eradicating virus from the patient. Senior study author, Dr. Leor S. Weinberger, a molecular virologist and systems biologist from the Department of Chemistry and Biochemistry at the University of California, San Diego, recently showed that noise in HIV gene-expression critically influences the viral decision to enter either active replication or latency. However, the source of the noise was not clear.

To probe the source of this inherent noise in HIV gene expression, Dr. Abhyudai Singh working in Dr. Weinberger's laboratory exploited a technique from electrical engineering that analyzes how noise changes across different levels of expression. The researchers examined cells carrying a single integrated copy of HIV engineered to produce a quantifiable protein, and measured HIV-1 expression noise at dozens of different viral integration sites which act as distinct genetic environments for viral gene expression.

Surprisingly, the authors find that HIV noise levels are substantially higher than measured in other organisms, and that HIV gene expression occurs in randomly timed bursts. During these expression bursts multiple copies of HIV gene products are produced which leads to the high noise levels in HIV gene expression. The bursting model argues that during active expression HIV cycles between periods of silence and bursting and provides insight into how HIV may be activated by host signaling molecules.

"We know that noise in gene-expression can critically influence HIV's entry to proviral latency. These new results point to transcriptional bursting as a major source of the noise" says Dr. Weinberger. "This finding that transcriptional bursting generates an exceptionally noisy HIV promoter, noisier than almost all other measured promoters, supports the theory that latency may be fundamental to the HIV life cycle and that HIV evolved for probabilistic entry into latency."

Researchers include Abhyudai Singh, University of California, San Diego, La Jolla, CA; Brandon Razooky, University of California, San Diego, La Jolla, CA; Chris D. Cox, University of Tennessee, Knoxville, TN; Michael L. Simpson, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN; and Leor S. Weinberger, University of California, San Diego, La Jolla, CA, Whitaker Institute for Biomedical Engineering, University of California, San Diego, La Jolla, CA


Story Source:

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


Journal Reference:

  1. Abhyudai Singh, Brandon Razooky, Chris D. Cox, Michael L. Simpson, Leor S. Weinberger. Transcriptional Bursting from the HIV-1 Promoter Is a Significant Source of Stochastic Noise in HIV-1 Gene Expression. Biophysical Journal, 2010; 98 (8): L32-L34 DOI: 10.1016/j.bpj.2010.03.001

Cite This Page:

Cell Press. "Researchers identify the source of 'noise' in HIV." ScienceDaily. ScienceDaily, 20 April 2010. <www.sciencedaily.com/releases/2010/04/100420132828.htm>.
Cell Press. (2010, April 20). Researchers identify the source of 'noise' in HIV. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2010/04/100420132828.htm
Cell Press. "Researchers identify the source of 'noise' in HIV." ScienceDaily. www.sciencedaily.com/releases/2010/04/100420132828.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