Featured Research

from universities, journals, and other organizations

Emerging Class Of Viruses Found To Change Shape To Infect Humans

Date:
December 27, 2004
Source:
Harvard Medical School
Summary:
The binding of a viral RNA and a viral protein brings about a physical transformation that dupes host cells into enthusiastically copying the invading pathogen, according to a team of researchers from Harvard Medical School (HMS) and Massachusetts Institute of Technology (MIT).

Boston (December 16, 2004) -- The binding of a viral RNA and a viral protein brings about a physical transformation that dupes host cells into enthusiastically copying the invading pathogen, according to a team of researchers from Harvard Medical School (HMS) and Massachusetts Institute of Technology (MIT).

In the December 17 issue of Science, collaborators led by professor Lee Gehrke of the Harvard-MIT Division of Health Sciences and Technology publish dramatic three-dimensional images of RNA-protein interactions in alfalfa mosaic virus (AMV), a safe model for investigating single-strand, positive-sense RNA viruses. AMV's dangerous relatives include flaviviruses that cause dengue fever, Japanese encephalitis and West Nile disease.

Gehrke and other molecular virologists knew that AMV was not infectious unless its genomic RNAs bound viral protein, but the details were unknown. Laura Guogas, a graduate student in Gehrke's lab, decided to seek answers with x-ray crystallography.

What Guogas found is "stunning and unexpected," says James Hogle, an structural biologist and professor of biological chemistry and molecular pharmacology at Harvard Medical School. He and David Filman, also of HMS, contributed to this study.<

RNA binding turned the viral coat protein from a floppy coil into a tight, springy helix. The RNA, a smooth strand punctuated by bumpy "hairpin structures," developed a kink that looks like a mountain turn on the Tour de France. The researchers attribute this kink to the formation of additional links between the two sides of the hairpins, another surprise from the three-dimensional structure. RNA and protein fold together in a way that locks them into place.

This distinctive, stable structure turns one end of the viral RNA into a handsome stranger. "It sticks out like a beacon compared with other RNAs in the cell," says Gehrke, who proposes that the host cell's replicating enzyme "jumps right on" and begins making more copies of the infecting virus.

Ordinarily, the translation of viral RNA into protein is triggered by a string of a particular RNA building block, adenosine, at one end of a typical RNA, a so-called "poly-A tail" that flaviviruses lack. AMV substitutes the striking RNA-protein complex that Guogas identified; other viruses in the family probably form different structures that make the ends of their RNA attractive to the cell's replicating machinery.

Future research will look for ways to translate differences between cellular and flavivirus RNAs into vaccines and treatments for dengue fever, West Nile virus, and similar emerging infections. The researchers hope to build on the synergy between biochemistry and structural biology demonstrated by Guogas's study. "This project is a great example of the role a talented student can play in a collaboration between two labs with complementary interests and expertise," says Hogle.


Story Source:

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


Cite This Page:

Harvard Medical School. "Emerging Class Of Viruses Found To Change Shape To Infect Humans." ScienceDaily. ScienceDaily, 27 December 2004. <www.sciencedaily.com/releases/2004/12/041219162121.htm>.
Harvard Medical School. (2004, December 27). Emerging Class Of Viruses Found To Change Shape To Infect Humans. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2004/12/041219162121.htm
Harvard Medical School. "Emerging Class Of Viruses Found To Change Shape To Infect Humans." ScienceDaily. www.sciencedaily.com/releases/2004/12/041219162121.htm (accessed October 21, 2014).

Share This



More Plants & Animals News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Goliath Spider Will Give You Nightmares

Goliath Spider Will Give You Nightmares

Buzz60 (Oct. 20, 2014) An entomologist stumbled upon a South American Goliath Birdeater. With a name like that, you know it's a terrifying creepy crawler. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
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


Plants & Animals

Earth & Climate

Fossils & Ruins

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