Featured Research

from universities, journals, and other organizations

Protein's ability to inhibit HIV release discovered

Date:
August 25, 2014
Source:
University of Missouri-Columbia
Summary:
A family of proteins that promotes virus entry into cells also has the ability to block the release of HIV and other viruses, researchers have found. The scientists performed a series of experiments that revealed the protein's ability to inhibit HIV-1 release, resulting in diminished viral production and replication.

A family of proteins that promotes virus entry into cells also has the ability to block the release of HIV and other viruses, University of Missouri researchers have found.

"This is a surprising finding that provides new insights into our understanding of not only HIV infection, but also that of Ebola and other viruses," said Shan-Lu Liu, MD, PhD, associate professor in the MU School of Medicine's Department of Molecular Microbiology and Immunology.

The study was recently published in the Proceedings of the National Academy of Sciences. Liu, the corresponding author of the study, is also an investigator with the Christopher S. Bond Life Sciences Center at MU.

According to estimates from the Centers for Disease Control and Prevention, more than one million Americans currently are living with HIV infection. AIDS, which stands for acquired immunodeficiency syndrome, is a condition characterized by progressive failure of the immune system. It is caused by the human immunodeficiency virus type 1 (HIV-1).

When HIV-1 or any virus infects a cell, it replicates and spreads to other cells. One type of cellular protein -- T cell immunoglobulin and mucin domain, or TIM-1 -- has previously been shown to promote entry of some highly pathogenic viruses into host cells. Now, the MU researchers have found that the same protein possesses a unique ability to block the release of HIV-1 and Ebola virus.

"This study shows that TIM proteins keep viral particles from being released by the infected cell and instead keep them tethered to the cell surface," said Gordon Freeman, PhD, an associate professor of medicine with Harvard Medical School's Dana-Farber Cancer Institute, who was not affiliated with the study. "This is true for several important enveloped viruses including HIV and Ebola. We may be able to use this insight to slow the production of these viruses."

Under the supervision of Liu, Minghua Li, a graduate student in the MU Pathobiology Area Program, performed a series of experiments that revealed the protein's ability to inhibit HIV-1 release, resulting in diminished viral production and replication.

HIV-1 attacks cells that are vital to the body's immune system, such as T cells. These white blood cells play an important role in the body's response to infection, but HIV-1 disrupts the cells' ability to fight back against infection. When the virus enters a host cell, it infects the cell and replicates, producing viral particles that spread to and infect other cells. The researchers found that as the viral particles attempt to bud from, or leave, the infected cell, the TIM-family proteins located on the surface of the cell can attach to lipids on the surface of the viral particle.

These lipids -- known as phosphatidylserine (PS) -- are normally present on the inner side of the cellular membrane but can be exposed to the outer side upon viral infection. When the TIM-family proteins come in contact with PS, the viral particle becomes attached to the host cell, keeping the particle from being released from the cell. Because TIM-family proteins and PS are present on the surface of the cell and the viral particle, the viral particles get stuck to one another, forming a network of viral particles that accumulate on the surface of the host cell, rather than being released to infect other cells.

By using molecular, biochemical and electron microscopic approaches, the researchers observed the TIM and PS interactions in human cells. The next step is for the researchers to study the biological significance of TIM-family proteins in animals and patients and to determine the fate of the infected cell once it accumulates a buildup of viral particles.

"We are not at the point to draw a conclusion as to whether this is a positive or a negative factor," Liu said. "However, this discovery furthers our ultimate goal of understanding the biology of TIM-family proteins and potentially developing applications for future antivirus therapies."

The study, "TIM-Family Proteins Inhibit HIV-1 Release," is supported in part by the National Institutes of Health and the University of Missouri. In addition to Liu and Li, researchers include Eric Freed, PhD, senior investigator with the National Cancer Institute (NCI) HIV Drug Resistance Program; Sherimay Ablan, biologist with the NCI HIV Drug Resistance Program; Marc Johnson, PhD, associate professor in the MU Department of Molecular Microbiology and Immunology; Chunhui Miao and Matthew Fuller, graduate students in the MU Department of Molecular Microbiology and Immunology; Yi-Min Zheng, MD, MS, senior research specialist with the Christopher S. Bond Life Sciences Center at MU; Paul Rennert, PhD, founder and principal of SugarCone Biotech LLC in Holliston, Massachusetts; and Wendy Maury, PhD, professor of microbiology at the University of Iowa.


Story Source:

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


Journal Reference:

  1. M. Li, S. D. Ablan, C. Miao, Y.-M. Zheng, M. S. Fuller, P. D. Rennert, W. Maury, M. C. Johnson, E. O. Freed, S.-L. Liu. TIM-family proteins inhibit HIV-1 release. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1404851111

Cite This Page:

University of Missouri-Columbia. "Protein's ability to inhibit HIV release discovered." ScienceDaily. ScienceDaily, 25 August 2014. <www.sciencedaily.com/releases/2014/08/140825185838.htm>.
University of Missouri-Columbia. (2014, August 25). Protein's ability to inhibit HIV release discovered. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/08/140825185838.htm
University of Missouri-Columbia. "Protein's ability to inhibit HIV release discovered." ScienceDaily. www.sciencedaily.com/releases/2014/08/140825185838.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How Nigeria Beat Its Ebola Outbreak

How Nigeria Beat Its Ebola Outbreak

Newsy (Oct. 20, 2014) The World Health Organization has declared Nigeria free of Ebola. Health experts credit a bit of luck and the government's initial response. Video provided by Newsy
Powered by NewsLook.com
Another Study Suggests Viagra Is Good For The Heart

Another Study Suggests Viagra Is Good For The Heart

Newsy (Oct. 20, 2014) An ingredient in erectile-dysfunction medications such as Viagra could improve heart function. Perhaps not surprising, given Viagra's history. Video provided by Newsy
Powered by NewsLook.com
Ebola Worries End for Dozens on U.S. Watch Lists

Ebola Worries End for Dozens on U.S. Watch Lists

Reuters - US Online Video (Oct. 20, 2014) Forty-three people who had contact with Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., were cleared overnight of twice-daily monitoring after 21 days of showing no symptoms. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
CDC Calls for New Ebola Safety Guidelines

CDC Calls for New Ebola Safety Guidelines

AP (Oct. 20, 2014) Centers for Disease Control and Prevention Director Dr. Tom Frieden laid out new guidelines for health care workers when dealing with the deadly Ebola virus including new precautions when taking off personal protective equipment. (Oct. 20) 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