MicroRNAs help control HIV life cycle

Jun 25, 2009

Scientists at Burnham Institute for Medical Research (Burnham) have discovered that specific microRNAs (non-coding RNAs that interfere with gene expression) reduce HIV replication and infectivity in human T-cells. In particular, miR29 plays a key role in controlling the HIV life cycle. The study suggests that HIV may have co-opted this cellular defense mechanism to help the virus hide from the immune system and antiviral drugs. The research was published today in the journal Molecular Cell.

Tariq Rana, Ph.D., director of the Program for RNA Biology at Burnham, and colleagues, found that the miR29 suppresses translation of the HIV-1 genome by transporting the HIV mRNA to processing-bodies (P-bodies), where they are stored or destroyed. This results in a reduction of and infectivity. The study also showed that inhibition of miR29 enhances viral replication and infectivity. The scientists further demonstrated that strains of HIV-1 with mutations in the region of the genome that interact with miR29 are not inhibited by miR29.

"We think the may use this mechanism to modulate its own lifecycle, and we may be able to use this to our advantage in developing for HIV," said Dr. Rana. "Retroviral therapies greatly reduce viral load but cannot entirely eliminate it. This interaction between HIV and miR29 may contribute to that inability. Perhaps, by targeting miR29, we can force HIV into a more active state and improve our ability to eliminate it."

Rana's team looked at miR29 expression levels in infected and uninfected cells and found that miR29 expression was enhanced by HIV-1 infection. Blocking the activity of miR29 with interfering RNA resulted in increased replication and infectivity of the virus. The scientists tested the association of miR29 and HIV-1 by mutating both miR29 and its target region on the . When either was altered, miR29s suppression of HIV replication and infectivity was reduced or eliminated. In addition, the team suppressed P-bodies in the cells and noted a similar effect. This suggests that HIV may use miRNAs to become dormant and escape immune response.

Source: Burnham Institute (news : web)

Explore further: Structure of sodium channels different than previously believed

add to favorites email to friend print save as pdf

Related Stories

Herpes drug inhibits HIV replication, but with a price

Nov 06, 2008

The anti-herpes drug acyclovir can also directly slow down HIV infection by targeting the reverse transcriptase (RT) enzyme, researchers report in this week's JBC. This beneficial effect does pose a risk though, as HIV-in ...

Immune exhaustion in HIV infection

May 06, 2008

As HIV disease progresses in a person infected with the HIV virus, a group of cells in the immune system, the CD8+ T lymphocytes, become “exhausted,” losing many of their abilities to kill other cells infected by the ...

Research findings open new front in fight against AIDS virus

Apr 28, 2008

A research group supported by the National Institutes of Health (NIH) has uncovered a new route for attacking the human immunodeficiency virus (HIV) that may offer a way to circumvent problems with drug resistance. In findings ...

MicroRNAs may be key to HIV's ability to hide, evade drugs

Sep 30, 2007

Tiny pieces of genetic material called microRNA (miRNA), better known for its roles in cancer, could be a key to unlocking the secrets of how HIV, the AIDS virus, evades detection, hiding in the immune system. Researchers ...

Recommended for you

Breakthrough points to new drugs from nature

Apr 16, 2014

Researchers at Griffith University's Eskitis Institute have developed a new technique for discovering natural compounds which could form the basis of novel therapeutic drugs.

World's first successful visualisation of key coenzyme

Apr 16, 2014

Japanese researchers have successfully developed the world's first imaging method for visualising the behaviour of nicotine-adenine dinucleotide derivative (NAD(P)H), a key coenzyme, inside cells. This feat ...

User comments : 0

More news stories

NASA's MMS observatories stacked for testing

(Phys.org) —Engineers at NASA's Goddard Space Flight Center in Greenbelt, Md., accomplished another first. Using a large overhead crane, they mated two Magnetospheric Multiscale, or MMS, observatories – ...