Featured Research

from universities, journals, and other organizations

Closer look at cells: Fluorescence microscopy lets scientists observe exchanges across cell membranes

Date:
July 28, 2011
Source:
Ecole Polytechnique Fédérale de Lausanne
Summary:
Many substances and nutrients are exchanged across the cell membrane. Scientists in Switzerland have developed a method to observe these exchanges, by taking a highly accurate count of the number of proteins found there.

Many substances and nutrients are exchanged across the cell membrane. Scientists at Ecole Polytechnique Fédérale de Lausanne in Switzerland have developed a method to observe these exchanges, by taking a highly accurate count of the number of proteins found there.

Their research has just been published in the online journal PLoS ONE.

Proteins on the cell surface play an essential role in the survival of the cell. They govern the exchanges between the interior and the exterior. Now, EPFL scientists have found a way to observe them in action. They have developed a method based on fluorescence microscopy that gives them a very precise image of the composition of the membrane and the exchanges taking place there. Their results are published July 26 in an article in Plos One, an online journal specializing in science and medicine, as well as in a June 12, 2011 letter to the journal Nature Methods.

"It is important to study the membrane because it is an exchange platform between the cell and its environment," explains Aleksandra Radenovic, Professor in the Laboratory of Nanoscale Biology and one of the study's authors.

Permeable to some molecules but closed off to others, the membrane controls the movement of substances and nutrients between the interior and the exterior of the cell. The proteins in the membrane play critical roles in the cell, particularly in energy transfer, gene expression and nutrient transport.

Using the method they developed, the scientists can now count these proteins very accurately. In so doing, they obtain valuable information on their interactions and their evolution. It allows them to know more about how a cell reacts to the administration of a drug or exposure to an external agent (such as a pollutant), and why a given cell behaves differently from another cell. "Eventually, this technique could thus help us develop more effective drugs," Radenovic says.

Capturing light

This research is based on very high resolution data provided by a special fluorescence microscopy technique called Photo Activated Localization Microscopy (PALM). Developed just under five years ago, this technology has revolutionized molecular imaging. It works on the principle of capturing light that is emitted -- either naturally or upon combination with a fluorescent substance (fluorochrome) -- by certain bodies at the nanometer scale.

Once the biological sample is placed under the microscope, the scientist "illuminates" the molecules with a series of successive flashes. The assemblage of images then forms a very high resolution image, which allows the scientists to pinpoint the location of proteins at extremely small scales.

The Laboratory of Nanoscale Biology is continuing its investigations, in order to refine the use of this technology and the quantification of elements present in the membrane in the most reliable manner possible. In particular, they are working on a "photoactivatable" protein called mEos2.


Story Source:

The above story is based on materials provided by Ecole Polytechnique Fédérale de Lausanne. Note: Materials may be edited for content and length.


Journal References:

  1. Paolo Annibale, Stefano Vanni, Marco Scarselli, Ursula Rothlisberger, Aleksandra Radenovic. Quantitative Photo Activated Localization Microscopy: Unraveling the Effects of Photoblinking. PLoS ONE, 2011; 6 (7): e22678 DOI: 10.1371/journal.pone.0022678
  2. Paolo Annibale, Stefano Vanni, Marco Scarselli, Ursula Rothlisberger, Aleksandra Radenovic. Identification of clustering artifacts in photoactivated localization microscopy. Nature Methods, 2011; 8 (7): 527 DOI: 10.1038/nmeth.1627

Cite This Page:

Ecole Polytechnique Fédérale de Lausanne. "Closer look at cells: Fluorescence microscopy lets scientists observe exchanges across cell membranes." ScienceDaily. ScienceDaily, 28 July 2011. <www.sciencedaily.com/releases/2011/07/110727121701.htm>.
Ecole Polytechnique Fédérale de Lausanne. (2011, July 28). Closer look at cells: Fluorescence microscopy lets scientists observe exchanges across cell membranes. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2011/07/110727121701.htm
Ecole Polytechnique Fédérale de Lausanne. "Closer look at cells: Fluorescence microscopy lets scientists observe exchanges across cell membranes." ScienceDaily. www.sciencedaily.com/releases/2011/07/110727121701.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) — Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) — A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) — The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) — A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. 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