Navigation Links
Carnegie Mellon scientists develop fluorescent proteins for live cell imaging, biosensor design
Date:2/6/2008

PITTSBURGH Scientists at Carnegie Mellon Universitys Molecular Biosensor and Imaging Center have developed new fluorogen activating proteins (FAPs) that will become a key component of novel molecular biosensor technology being created at Carnegie Mellon. The FAPs, which can be used to monitor biological activities of individual proteins and other biomolecules within living cells in real time, are described in the February issue of Nature Biotechnology.

Carnegie Mellon scientists designed the FAPs to emit fluorescent light only when bound to a fluorogen, an otherwise non-fluorescent dye added by the scientists. This feature will allow biologists to track proteins on the cell surface and within living cells in very simple and direct ways, eliminating cumbersome experimental steps.

Scientists say the fluorogen activating proteins are especially useful for developing molecular biosensors, because FAPs allow researchers to not only see where the target protein is within the space of the cell, but also to see color changes when it becomes fluorescent. Color changes may reflect changes in the local environment of the protein, and allow quantitative sensing in real time of the biological activity of proteins and biomolecules that are in close proximity to each other.

Biologists often have a difficult time locating a target biomolecule inside living cells using other dye technologies because of background light given off by any unbound dye molecules. This background light obscures the biomolecules glow and therefore must be removed to successfully carry out the experiment.

The new FAP technology gives off light only when and precisely where the target biomolecule is present, enabling scientists to activate the fluorescence when needed to see exactly where in the cell the biomolecule is located. Scientists also can design fluorogens that can enter the cell and fluorogens that cant. When used with fluorogens that are excluded from the cell, the FAP technology provides an exceptionally selective biosensor for proteins at the outside of the cell surface.

The FAP is a specialized single chain antibody (scFv), a recombinant fragment of full-size antibody proteins that the human immune system uses to identify intruders like bacteria or viruses. The Carnegie Mellon scientists screened billions of scFvs to look for those that bound specifically to either of two fluorogens, malachite green and thiazole orange. The team found several scFvs that, when bound to the fluorogen, emitted bright fluorescent signals. They termed these scFvs fluorogen activating proteins.

These FAPs are the essential first step in developing molecular biosensors that will monitor dynamic changes occurring within cells, said Alan Waggoner, professor of biological sciences and director of the Molecular Biosensor and Imaging Center (MBIC). The ultimate goal is to put molecular biosensors based on FAP technology inside cells, but this current work is immediately useful. We have used the FAPs in conjunction with several fluorogens to visualize proteins at the cell surface and are now using the technology to image proteins inside cells.

The new FAPs are an extension of the genetic approach made popular by the advent of fluorescent proteins, such as green fluorescent protein (GFP), more than a decade ago. GFPs, once expressed in cells, are always aglow when visualized by scientists using special light sources and microscopes. The Carnegie Mellon team has taken GFP technology one step further with the novel FAPs and associated fluorogens, they can control fluorescence in space and time.

The beauty of our system is that we can make FAPs with genetic variations so that we can co-express distinct FAPs within a cell. We can also make synthetic variations of the fluorogen that have different fluorescent and binding properties. Together, these modifications will allows us to image multiple colors inside cells, enabling us to dynamically monitor several proteins and follow complex cellular functions, said Chris Szent-Gyorgyi, a research scientist at the MBIC who spearheaded the isolation of the FAPs.


'/>"/>

Contact: Jocelyn Duffy
jhduffy@andrew.cmu.edu
412-268-9982
Carnegie Mellon University
Source:Eurekalert

Related biology news :

1. Carnegie Mellon scientists develop nanogels that enable controlled delivery of carbohydrate drugs
2. Carnegie Mellon scientists investigate initial molecular mechanism that triggers neuronal firing
3. Carnegie Mellon scientist uses mass spectrometer to weigh virus particle, von Willebrand factor
4. Carnegie Mellon, Pitt Team to study psychosocial stress
5. Mellon awards Carnegie Grant for Ecological Monitoring in South Africa
6. Carnegie Mellon researchers to develop new drug delivery system
7. Carnegie Mellon students win contest
8. Novel mechanism for long-term learning identified by Carnegie Mellon researchers
9. U. Mass Medical School and Carnegie announce licensing agreements with Oxford BioMedica
10. UK scientists working to help cut ID theft
11. Scientists show that mitochondrial DNA variants are linked to risk factors for type 2 diabetes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/22/2016)... June 22, 2016 On Monday, the Department ... industry to share solutions for the Biometric Exit Program. ... and Border Protection (CBP), explains that CBP intends to ... the United States , in order ... defeat imposters. Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/9/2016)... June 9, 2016  Perkotek an innovation leader in attendance control systems is proud ... work hours, for employers to make sure the right employees are actually signing in, ... ... ... ...
(Date:6/2/2016)... 2, 2016   The Weather Company , an IBM ... an industry-first capability in which consumers will be able to ... ask questions via voice or text and receive relevant information ... Marketers have long sought an advertising solution that ... be personal, relevant and valuable; and can scale across millions ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... ... findings on what they believe could be a new and helpful biomarker for ... research. Click here to read it now. , Biomarkers are components ...
(Date:6/27/2016)... -- Liquid Biotech USA , Inc. ... Research Agreement with The University of Pennsylvania ("PENN") ... patients.  The funding will be used to assess ... outcomes in cancer patients undergoing a variety of ... to support the design of a therapeutic, decision-making ...
(Date:6/24/2016)... ... , ... While the majority of commercial spectrophotometers and fluorometers use the z-dimension ... are higher end machines that use the more unconventional z-dimension of 20mm. Z-dimension ... bottom of the cuvette holder. , FireflySci has developed several Agilent flow cell ...
(Date:6/23/2016)... , June 23, 2016   Boston ... of novel compounds designed to target cancer stemness ... has been granted Orphan Drug Designation from the ... treatment of gastric cancer, including gastroesophageal junction (GEJ) ... inhibitor designed to inhibit cancer stemness pathways by ...
Breaking Biology Technology: