Featured Research

from universities, journals, and other organizations

How embryos fight retroviral infection

Date:
June 24, 2010
Source:
Texas A&M University
Summary:
Some viruses insert themselves into the host's DNA during infection in a process called retroviral integration, causing several diseases, including AIDS and cancer, notes a researcher who specializes in fetal diseases. However, stem cells that give rise to the early embryo and yolk sac fight back, inhibiting further infection by aggressively silencing the invading viral DNA, he says.

Some viruses insert themselves into the host's DNA during infection in a process called retroviral integration, causing several diseases, including AIDS and cancer, notes a Texas A&M researcher who specializes in fetal diseases. However, stem cells that give rise to the early embryo and yolk sac fight back, inhibiting further infection by aggressively silencing the invading viral DNA, says Michael Golding of the Department of Veterinary Physiology and Pharmacology.

The work of the researcher was recently published in Cell Stem Cell.

Early mammalian embryos actually possess three stem cell lineages: ES (embryonic stem), TS (trophectoderm stem), and XEN (extraembryonic endoderm), which give rise to the fetus, placenta and yolk sac respectively, the Texas A&M researcher explains. Using the mouse as a model organism, Golding and his colleagues demonstrate that the mechanisms silencing gene expression are different between each of the three stem cell types.

"Much like a closed book cannot be read while an open book can, the DNA encoding genes can either be tightly wound up and silent or in a relaxed, open, active state," Golding explains. "The mechanisms that control this gene packaging are called epigenetic as they represent a level of regulation that is above or 'epi' to genetics."

The study shows "retroviral silencing in XEN cells is epigenetic in origin" and that "the three cell lineages of early mammalian embryo have vastly different viral silencing strategies as well as different capacities to suppress retroviral activity."

To examine the validity of a common assumption that these stem cells use similar mechanisms to silence retroviruses, Golding infected the mouse embryo stem cells with mouse leukemia virus (MLV) and monitored the virus' activity.

ES cells showed a progressive decline in virus activity, while TS cells had a constant level of virus activity. XEN cells, however, exhibited extremely aggressive and rapid silencing of virus activity, according to the study.

"Epigenetics is an exciting new field of research which is altering the way we think about fetal nutrition and exposure to environmental chemicals," Golding adds. "This discovery that all three stem cell types of the early embryo utilize slightly different mechanisms to control gene expression has profound implications for how we diagnose and treat fetal diseases."


Story Source:

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


Journal Reference:

  1. Golding et al. Multiple Epigenetic Modifiers Induce Aggressive Viral Extinction in Extraembryonic Endoderm Stem Cells. Cell Stem Cell, 2010; 6 (5): 457 DOI: 10.1016/j.stem.2010.03.014

Cite This Page:

Texas A&M University. "How embryos fight retroviral infection." ScienceDaily. ScienceDaily, 24 June 2010. <www.sciencedaily.com/releases/2010/06/100624112308.htm>.
Texas A&M University. (2010, June 24). How embryos fight retroviral infection. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2010/06/100624112308.htm
Texas A&M University. "How embryos fight retroviral infection." ScienceDaily. www.sciencedaily.com/releases/2010/06/100624112308.htm (accessed August 21, 2014).

Share This




More Health & Medicine News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Reasons Why Teen Birth Rates Are At An All-Time Low

Reasons Why Teen Birth Rates Are At An All-Time Low

Newsy (Aug. 20, 2014) A CDC report says birth rates among teenagers have been declining for decades, reaching a new low in 2013. We look at several popular explanations. Video provided by Newsy
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:
from the past week

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