22-Sep-2011 - A new computational approach has predicted numerous human proteins that the human immunodeficiency
virus (HIV) requires to replicate itself, and "constitutes a powerful resource for experimentalists who desire to discover new human proteins
that can control the spread of HIV," according to the authors of a study, which will be published in the open-access journal PLoS
Computational Biology on Thursday 22nd September 2011.
"Drugs used to cure HIV become rapidly ineffective because HIV is able to develop mutations against drugs," author T. M. Murali
of Virginia Tech's Department of Computer Science explained. Since viruses such as HIV have very small genomes, they must exploit the cellular
machinery of the host to spread. Researchers are examining whether human proteins can be targeted to cure HIV as they evolve at a much slower
rate than HIV proteins and accordingly are unlikely to develop mutations that render the drugs ineffective.
Many hundreds of HIV Dependency Factors (HDFs) have already been discovered but the authors hypothesized that it would be
possible to predict new HDFS by their placement within networks of interacting human proteins. To this end, they created an algorithm
called SinkSource.
Brett Tyler, of the Virginia Bioinformatics Institute at Virginia Tech, explained the algorithm using this analogy: "We
treated the human protein network as if it were a system of tanks connected by pipes carrying water. This arrangement allowed us to
study the flow of predictive information (water) from proteins we are certain about (full tanks) to those we are uncertain about
(empty tanks). The further you get from the full tanks, the weaker the trickle, and the less water accumulates in the bottom
of the tank. Mathematically you can show that, over time, every empty tank accumulates some stable level of water. At the
end of the analysis, tanks accumulating lots of water were judged to be good predictions."
The authors found that SinkSource made predictions of high quality and used the algorithm to analyze HDF activities in two
non-human primate species infected with Simian Immunodeficiency Virus (SIV), one of which develops disease and one of which doesn't.
Using data already published by author Michael G. Katze, associate director of the Washington National Primate Research Center, the
authors showed that predicted HDFs had very different patterns of expression in the two species, especially in lymph nodes and
within 10 days after infection with the virus.
The authors concluded that many HDFs are yet to be discovered and they have potential value as prognostic markers to
determine pathological outcome and the likelihood of Acquired Immune Deficiency Syndrome (AIDS) development.
###
FINANCIAL DISCLOSURE: Public Health Service grants P30DA015625, P51RR000166, and R24RR016354 from the
National Institutes of Health to MGK, grants from the Virginia Bioinformatics Institute Fellows program to TMM and BMT, and a grant
from the ASPIRES program at the Virginia Polytechnic Institute and State University to TMM supported this research. The funders
had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
COMPETING INTERESTS: I have read the journal's policy and have the following conflicts: MDD is employed
by and owns stock in Life Technologies.
CITATION: Murali TM, Dyer MD, Badger D, Tyler BM, Katze MG (2011) Network-Based Prediction and Analysis of
HIV Dependency Factors. PLoS Comput Biol 7(9): e1002164. doi:10.1371/journal.pcbi.1002164
PLEASE ADD THIS LINK TO THE FREELY AVAILABLE ARTICLE IN ONLINE VERSIONS OF YOUR REPORT (the link will go live when the embargo
ends): http://www.ploscompbiol.org/doi/pcbi.1002164
CONTACT:
Lynn Nystrom, Director of News and External Relations, College of Engineering, Virginia Tech
Email: tasy@vt.edu
Telephone: 540 231 4371
Disclaimer
This press release refers to an upcoming article in PLoS Computational Biology . The release is provided by journal
staff, or by the article authors and/or their institutions. Any opinions expressed in this release or article are the personal views of the
journal staff and/or article contributors, and do not necessarily represent the views or policies of PLoS. PLoS expressly disclaims any
and all warranties and liability in connection with the information found in the releases and articles and your use of such information.
Media Permissions
PLoS Journals publish under a Creative Commons Attribution License ( http://creativecommons.org/licenses/by/2.5/ ), which
permits free reuse of all materials published with the article, so long as the work is cited (e.g., Brinkworth RSA, O'Carroll DC (2009)
Robust Models for Optic Flow Coding in Natural Scenes Inspired by Insect Biology. PLoS Comput Biol 5(11): e1000555. doi:10.1371/journal.pcbi.1000555). No
prior permission is required from the authors or publisher. For queries about the license, please contact the relative journal contact indicated
here: http://www.plos.org/journals/embargopolicy.php
About PLoS Computational Biology
PLoS Computational Biology ( www.ploscompbiol.org ) features
works of exceptional significance that further our understanding of living systems at all scales through the application of computational
methods. All works published in PLoS Computational Biology are open access. Everything is immediately available subject only
to the condition that the original authorship and source are properly attributed. Copyright is retained.
About the Public Library of Science
The Public Library of Science (PLoS) is a non-profit organization of scientists and physicians committed to making the world's
scientific and medical literature a freely available public resource. For more information,
visit http://www.plos.org .
Emily Rios
erios@emory.edu
404-727-7732
Emory University
Source: EurekAlert!
http://www.eurekalert.org/pub_releases/2011-09/plos-nhp091511.php
|