Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tracking viral DNA in the Cell

17.10.2013
Cell biologists and chemists from the University of Zurich 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.

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).
Literature:
I-Hsuan Wang, Maarit Suomalainen, Vardan Andriasyan, Samuel Kilcher, Jason Mercer, Anne Neef, Nathan W. Luedtke & Urs F. Greber. Tracking viral genomes in host cells at single molecule resolution. Cell Host Microbe, October 16, 2013. http://dx.doi.org/10.1016/j.chom.2013.09.004
Contacts:
Prof. Dr. Urs Greber
Institute of Molecular Life Sciences
University of Zurich
Tel. +41 44 635 48 41
E-Mail: urs.greber@imls.uzh.ch

Nathalie Huber | Universität Zürich
Further information:
http://www.mediadesk.uzh.ch

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>