Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Tagging Technique Enhances View of Living Cells

05.08.2010
Scientists hoping to understand how cells work may get a boost from a new technique to tag and image proteins within living mammalian cells.

The new technique, developed by a research team led by University of Illinois at Chicago assistant professor of chemistry Lawrence Miller, provides the clearest, most dynamic view yet of protein-protein interactions in cells when viewed through a specially modified microscope.

The finding is reported in the Proceedings of the National Academy of Sciences (advanced online July 19.)

Knowing where and when particular proteins interact within the cell is key to understanding life processes at the molecular level.

In a technique called luminescence resonance energy transfer, two proteins in a cell are labeled with differently colored, luminescent molecules that absorb light of one color and give it off as another color. By taking several pictures of the cell and mathematically analyzing the pictures, researchers gain information about the proteins' precise location and whether they are interacting.

Miller and his team used a novel type of luminescent molecule for labeling, making it possible to get the same information using fewer pictures. This simplifies the analysis and allows for five-fold faster data acquisition. Images show a 50-fold improvement in sensitivity.

Working with Jerrold Turner, professor and associate head of pathology at the University of Chicago, Miller used a hybrid chemical/genetic approach to tag the proteins of interest. One of the proteins was genetically modified so that it would bind to a terbium complex. The terbium complex has an unusually long time between light absorption and emission. The second target protein was genetically modified to link to a fluorescent tag with a short emission lifetime. When the two proteins interact, the luminescent tags are brought very close together, generating a unique luminescent signal that can be seen under a microscope.

Miller and his colleagues modified a conventional microscope to exploit the long lifetime of the terbium protein tags. Pulsed light is used to trigger the terbium luminescence, detected after the other luminescent species within cells have gone dark, allowing unwanted background to be removed from the image.

The new technique "increases sensitivity and makes the whole process faster," Miller said. "This increases the time-resolution of the experiment, allowing you to see how interactions change on a faster time scale, which can help to better figure out how certain biological phenomena work."

The technique required a reliable way to deliver the luminescent terbium probe through a living cell membrane without contaminating or damaging the cell. The researchers developed a way to co-opt pinocytosis, the process by which cells drink in small amounts of surrounding fluid.

"With this new tool, we hope cell biologists and others will be able to study things they haven't seen before, such as interactions that couldn't be visualized in live cells in real time," Miller said. "Hopefully the method will yield information that makes it easier to deduce biological mechanisms."

Other authors include UIC graduate students Harsha Rajapakse (the lead author), Nivriti Gahlaut and Shabnam Mohandessi and University of Chicago graduate student Dan Yu. The terbium tag was developed in collaboration with Richmond, Calif.-based Lumiphore, Inc. Major funding was provided by the National Institutes of Health and the Chicago Biomedical Consortium.

Paul Francuch | Newswise Science News
Further information:
http://www.uic.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>