Featured Research

from universities, journals, and other organizations

Engineered coral pigment helps scientists to observe protein movement

Date:
July 27, 2010
Source:
National Oceanography Centre, Southampton (UK)
Summary:
Scientists have shown that a variant form of a fluorescent protein originally isolated from a reef coral has excellent properties as a marker protein for super-resolution microscopy in live cells.

Fluorescence of mouth region of the reef coral Lobophyllia hemprichii.
Credit: Image courtesy of National Oceanography Centre, Southampton (UK)

Scientists in Southampton, UK, and Ulm and Karlsruhe in Germany have shown that a variant form of a fluorescent protein (FP) originally isolated from a reef coral has excellent properties as a marker protein for super-resolution microscopy in live cells.

Related Articles


Their findings have been published online by Nature Methods and will appear in print in the upcoming August issue of that journal.

Fluorescent proteins produced by a range of marine animals glow with a rainbow of colours, adding to the visual spectacle of coral reefs. Over recent years, molecular biologists have isolated a number of FPs and their genes, and used them to create genetically engineered variant FPs with particular light-emission characteristics.

"Fluorescent pigments from corals and related animals have proved to be invaluable lead structures to produce advanced markers for biomedical research," said Dr Jörg Wiedenmann of the University of Southampton's School of Ocean and Earth Science (SOES) based at the National Oceanography Centre, Southampton: "They enable a plethora of exciting experiments, including non-invasive study of dynamical processes within live cells,"

Photoactivatable FPs (PA-FPs)can, as their name suggests, be switched on by light. When light of a particular wavelength is shone upon them they start to glow, emitting light of characteristic hue.

Wiedenmann and his collaborators previously described EosFP, a PA-FP from the reef-building coral Lobophyllia. Genetic engineering yielded the variant IrisFP with dual photoactivation capacity. In one mode it is irreversibly 'photo-converted' from a green- to a red-emitting form under violet light. In a second mode, these two light-emitting forms can be switched on and off more or less at will using light of different wavelengths ('photo-switching').

For use in cell biology experiments, PA-FPs are genetically fused to proteins of interest, and expressed in live cells. Small regions of the cell are then illuminated with laser light of specific wavelength, causing the marker proteins to emit light at another wavelength. This allows dynamical cell processes to be visualised and studied under the microscope.

In the native state, four molecules of IrisFP join together to form a tetramer, creating problems for fusion-protein applications. To get round this, the researchers have now modified the protein by introducing four mutations. This makes individual IrisFP molecules (monomers) more stable, reducing their tendency for form tetramers.

"The monomeric variant, mIrisFP, maintains dual photoactivation capacity and has excellent properties as a genetically encoded fluorescent marker protein," explained Wiedenmann.

To test the usefulness of mIrisFP, the researchers genetically fused it with a number of other proteins within cultured cells. These included transcription factors, which regulate the expression of genes within the cell nucleus, and constituent proteins of the cell skeleton ('cytoskeleton'). In all cases, the fusion proteins functioned normally.

Further experiments demonstrated that mIrisFP fusion proteins could, as hoped, be used to study dynamical processes within live cells with a spatial resolution beyond the limits of conventional light microscopy. Specifically, the researchers successfully combined so-called pulse-chase experiments with photoactivation localisation microscopy (PALM) imaging to follow the movement of fluorescently marked fusion proteins over time and at very high spatial resolution.

"The dual photoactivation capability and the monomeric nature of mIrisFP should allow cell biologists to perform a wider range of experiments than possible using only conventional PA-FPs," said Wiedenmann.

"Marine animals such as corals and anemones are not only beautiful and important for ecosystem functioning, but also as source of fluorescent proteins of enormous value to biomedical research," he added.

The research was supported supported by the Deutsche Forschungsgemeinschaft and the State of Baden-Württemberg through the Center for Functional Nanostructures, by Deutsche Forschungsgemeinschaft grant NI 291/9, Landesstiftung Baden-Württemberg and Fonds der Chemischen Industrie.

The researchers are Jochen Fuchs, Susan Boehme,Per Niklas Hedde and Ulrich Nienhaus(Karlsruhe Institute of Technology),Franz Oswald(University of Ulm), Maike Krause (Institute of Biophysics, Ulm), and Jörg Wiedenmann(SOES).


Story Source:

The above story is based on materials provided by National Oceanography Centre, Southampton (UK). Note: Materials may be edited for content and length.


Journal Reference:

  1. Fuchs, J., Boehme, S., Oswald, F., Hedde, P. N., Krause, M., Wiedenmann, J. & Nienhaus, G. U. A photoactivatable marker protein for pulse-chase imaging with superresolution. Nature Methods, 2010; DOI: 10.1038/nmeth.147

Cite This Page:

National Oceanography Centre, Southampton (UK). "Engineered coral pigment helps scientists to observe protein movement." ScienceDaily. ScienceDaily, 27 July 2010. <www.sciencedaily.com/releases/2010/07/100727112835.htm>.
National Oceanography Centre, Southampton (UK). (2010, July 27). Engineered coral pigment helps scientists to observe protein movement. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2010/07/100727112835.htm
National Oceanography Centre, Southampton (UK). "Engineered coral pigment helps scientists to observe protein movement." ScienceDaily. www.sciencedaily.com/releases/2010/07/100727112835.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) — The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Kids Die While Under Protective Services

Kids Die While Under Protective Services

AP (Dec. 18, 2014) — As part of a six-month investigation of child maltreatment deaths, the AP found that hundreds of deaths from horrific abuse and neglect could have been prevented. AP's Haven Daley reports. (Dec. 18) Video provided by AP
Powered by NewsLook.com
When You Lose Weight, This Is Where The Fat Goes

When You Lose Weight, This Is Where The Fat Goes

Newsy (Dec. 17, 2014) — Can fat disappear into thin air? New research finds that during weight loss, over 80 percent of a person's fat molecules escape through the lungs. Video provided by Newsy
Powered by NewsLook.com
The Hottest Food Trends for 2015

The Hottest Food Trends for 2015

Buzz60 (Dec. 17, 2014) — Urbanspoon predicts whicg food trends will dominate the culinary scene in 2015. Mara Montalbano (@maramontalbano) has the story. Video provided by Buzz60
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