Featured Research

from universities, journals, and other organizations

Tracking viral DNA in the cell: New method to generate virus particles containing labeled viral DNA genomes

Date:
October 16, 2013
Source:
University of Zurich
Summary:
Cell biologists and chemists reveal how viral DNA traffics in human cells. They have developed a new method to generate virus particles containing labeled viral DNA genomes. This allowed them to visualize, for the first time, single viral genomes in the cytoplasm and the nucleus by using fluorescence microscopy in regular or superresolution mode. The new findings enhance our understanding of how viral disease occurs, and how cells respond to infections.

Grape-like structures of viral replication territories in the nucleus of a human cell visualized by click-chemistry and immuno-fluorescence confocal microscopy. Newly synthesized adenoviral DNA labeled by click chemistry is depicted in red, a viral DNA-binding protein in green, and the cellular DNA in blue. The cell nucleus with a faint blue periphery is 18 x 22 micrometers in size.
Credit: Nathalie Huber

The medical, humanitarian and economical impact of viral diseases is devastating to humans and livestock. There are no adequate therapies available against most viral diseases, largely because the mechanisms by which viruses infect cells are poorly known. An interdisciplinary team of researchers from the University of Zurich headed by cell biologist Prof. Urs Greber now presents a method that can be used to display viral DNA in host cells at single-molecule resolution. The method gives unexpected insights into the distribution of viral DNA in cells, and the reaction of cells to viral DNA.

Click chemistry detects viral DNA

For their studies, Greber and his team with PhD students I-Hsuan Wang, Vardan Andriasyan and senior research scientist Dr. Maarit Suomalainen used cell cultures and human adenoviruses causing respiratory disease and conjunctivitis, herpes viruses and vaccinia virus, the latter in collaboration with Dr. Jason Mercer and his PhD student Samuel Kilcher from the ETH Zurich. To label the DNA of an intact virus, the scientists turned to click chemistry -- widely applicable chemical reaction types. Prof. Nathan Luedtke from the Institute of Organic Chemistry at the University of Zurich, and PhD student Anne Neef developed a new class of "clickable" chemical molecules. "Our molecule is incorporated into viral DNA without affecting the biological functions of the DNA, and it can be used to label the DNA for fluorescence microscopy," says Luedtke.

Defense response of infected cells visible for the first time

Greber and his team infected human cells in culture with the chemically labeled viruses, and observed the behavior of the viral DNA during entry into cells. "Using this elegant method, we can reveal that not all the incoming viral DNA enters the cell nucleus as originally expected, but a significant fraction remains in the cytosol, the fluids of the cytoplasm," explains Greber. According to the scientists, this phenomenon may be part of the antiviral defense reaction. "For the first time, we can display the localization of incoming viral DNA, and link it to anti-viral defense or infection mechanisms," says Greber. The researchers show that cells of the same type take up different amounts of viral DNA into their nucleus. Greber suspects that the nucleus has antiviral defense reactions, akin to the cytosol, and these defense reactions are variable between cells. With the new method in hand, this is now subject to future studies. The scientists suggest that their procedure can be applied to other DNA viruses, or the HI virus (HIV).


Story Source:

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


Journal Reference:

  1. I-Hsuan Wang, Maarit Suomalainen, Vardan Andriasyan, Samuel Kilcher, Jason Mercer, Anne Neef, NathanW. Luedtke, UrsF. Greber. Tracking Viral Genomes in Host Cells at Single-Molecule Resolution. Cell Host & Microbe, 2013; 14 (4): 468 DOI: 10.1016/j.chom.2013.09.004

Cite This Page:

University of Zurich. "Tracking viral DNA in the cell: New method to generate virus particles containing labeled viral DNA genomes." ScienceDaily. ScienceDaily, 16 October 2013. <www.sciencedaily.com/releases/2013/10/131016123034.htm>.
University of Zurich. (2013, October 16). Tracking viral DNA in the cell: New method to generate virus particles containing labeled viral DNA genomes. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2013/10/131016123034.htm
University of Zurich. "Tracking viral DNA in the cell: New method to generate virus particles containing labeled viral DNA genomes." ScienceDaily. www.sciencedaily.com/releases/2013/10/131016123034.htm (accessed July 23, 2014).

Share This




More Plants & Animals News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Stone Fruit Listeria Scare Causes Sweeping Recall

Stone Fruit Listeria Scare Causes Sweeping Recall

Newsy (July 22, 2014) The Wawona Packing Company has issued a voluntary recall on the stone fruit it distributes due to a possible Listeria outbreak. Video provided by Newsy
Powered by NewsLook.com
Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
CDC Head Concerned About a Post-Antibiotic Era

CDC Head Concerned About a Post-Antibiotic Era

AP (July 22, 2014) Sounding alarms about the growing threat of antibiotic resistance, CDC Director Tom Frieden warned Tuesday if the global community does not confront the problem soon, the world will be living in a devastating post-antibiotic era. (July 22) 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:
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