Featured Research

from universities, journals, and other organizations

Watching molecule movements in live cells

Date:
July 24, 2013
Source:
Karlsruhe Institute of Technology
Summary:
The newly developed STED-RICS microscopy method records rapid movements of molecules in live samples. By combining raster image correlation spectroscopy (RICS) with STED fluorescence microscopy, researchers have opened up new applications in medical research, e.g. analyzing the dynamics of cell membranes at high protein concentrations.

The STED-RICS microscope scans the fluorescent cell membrane with a light spot and, thus, an image is recorded.
Credit: P. N. Hedde/KIT

The newly developed STED-RICS microscopy method records rapid movements of molecules in live samples. By combining raster image correlation spectroscopy (RICS) with STED fluorescence microscopy, researchers of Karlsruhe Institute of Technology (KIT) opened up new applications in medical research, e.g. analyzing the dynamics of cell membranes at high protein concentrations.

Related Articles


This method is now presented in Nature Communications.

How do individual biomolecules move in live cells, tissues, or organisms? How do the biomolecules interact? These questions have to be answered to better understand the processes of life on the molecular level. STED fluorescence microscopy allows to pursue the movements and interactions of biomolecules in live samples with high spatial and temporal resolution. For this purpose, the structures to be studied are marked selectively using fluorescent dyes. Then, changes with time can be videotaped. However, the image sequence is rather slow, such that rapid molecule movements cannot be recorded directly. A group of KIT researchers around Professor Gerd Ulrich Nienhaus from the Institute of Applied Physics (APH) and the Center for Functional Nanostructures (CFN) now presents a new method to measure such rapid molecule movements in live samples in the Nature Communications journal.

The new method combines two types of microscopy. Using a confocal scanning microscope, fluorescence images are recorded point by point at fixed time intervals. Hence, the images contain an implicit time structure. This information can be used with the help of raster image correlation spectroscopy (RICS) to determine the dynamics of biomolecules, such as proteins, in live cells or tissue samples. However, protein concentrations often are too high to apply RICS together with conventional microscopy. For this reason, the KIT researchers combined the RICS method with STED microscopy (stimulated emission depletion microscopy). When using STED, the light spot scanning the fluorescence image can be reduced considerably. This method has already been used successfully to reach a maximum resolution in the imaging of cells. A STED microscope is a fluorescence microscope, whose resolution is not limited by the Abbe limit.

By combining raster image correlation spectroscopy with STED microscopy, KIT researchers have now succeeded in quantifying molecule dynamics in biological structures based on the raster images recorded. "This means that the STED-RICS method can be used to derive from any fluorescence image a highly resolved map of the number and movability of the marked molecules in the area scanned by the spot," Gerd Ulrich Nienhaus explains.

Professor Nienhaus' working group consists of physicists, chemists, and biologists. Interdisciplinary cooperation is indispensable to cover all aspects when developing new microscopic instruments and methods for biophysical fundamental research. When applications are addressed, other KIT researchers join the team and contribute their knowledge of molecular processes. In the case of the STED-RICS method, the team worked together with scientists from the Institute of Toxicology and Genetics (ITG) and the Cell and Developmental Biology Division of the Zoological Institute.

The STED-RICS method opens up new measurement applications in life sciences. A major application is research into the dynamics of cell membranes. Numerous receptor proteins are embedded in the membranes. By interaction with externally docking ligand molecules, external signals are transmitted into the cell. With the help of STED-RICS, the researchers can now determine precisely and quantitatively the movements of both lipids and receptors. Understanding of these processes is of crucial importance to medical and pharmaceutical research. Many pharmaceutical substances are based on influencing these interactions. "About every second medical substance influences signal transduction of G-protein coupled receptors, an important sub-class," Professor Nienhaus explains.


Story Source:

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


Journal Reference:

  1. Per Niklas Hedde, Renι M. Dφrlich, Rosmarie Blomley, Dietmar Gradl, Emmanuel Oppong, Andrew C.B. Cato, G. Ulrich Nienhaus. Stimulated emission depletion-based raster image correlation spectroscopy reveals biomolecular dynamics in live cells. Nature Communications, 2013; 4 DOI: 10.1038/ncomms3093

Cite This Page:

Karlsruhe Institute of Technology. "Watching molecule movements in live cells." ScienceDaily. ScienceDaily, 24 July 2013. <www.sciencedaily.com/releases/2013/07/130724102607.htm>.
Karlsruhe Institute of Technology. (2013, July 24). Watching molecule movements in live cells. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2013/07/130724102607.htm
Karlsruhe Institute of Technology. "Watching molecule movements in live cells." ScienceDaily. www.sciencedaily.com/releases/2013/07/130724102607.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) — Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) — One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) — Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. 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:

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