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 August 20, 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 August 20, 2014).

Share This




More Plants & Animals News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Disquieting Times for Malaysia's 'fish Listeners'

Disquieting Times for Malaysia's 'fish Listeners'

AFP (Aug. 19, 2014) Malaysia's last "fish listeners" -- practitioners of a dying local art of listening underwater to locate their quarry -- try to keep the ancient technique alive in the face of industrial trawling and the depletion of stocks. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
USDA Cracks Down On Imports From Foreign Puppy Mills

USDA Cracks Down On Imports From Foreign Puppy Mills

Newsy (Aug. 18, 2014) New USDA measures to regulate dog imports aim to crack down on buying dogs from overseas puppy mills. Video provided by Newsy
Powered by NewsLook.com
Bone Marrow Drug Regrows Hair In Some Alopecia Patients

Bone Marrow Drug Regrows Hair In Some Alopecia Patients

Newsy (Aug. 18, 2014) Researchers performed an experiment using an FDA-approved drug known as ruxolitinib. They found it to be successful in the majority of patients. 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