Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Develop Powerful Fluorescence Tool, Light the Way to New Insights Into RNA of Living Cells

01.08.2011
The ability to tag proteins with a green fluorescent light to watch how they behave inside cells so revolutionized the understanding of protein biology that it earned the scientific teams who developed the technique Nobel Prizes in 2008. Now, researchers at Weill Cornell Medical College have developed a similar fluorescent tool that can track the mysterious workings of the various forms of cellular RNA.

In the July 29 issue of Science, the Weill Cornell investigators report how they developed an RNA mimic of green fluorescent protein (GFP) -- which they dubbed Spinach -- and describe how it will help unlock the secrets of the complex ways that RNA sustains human life as well as contributes to disease.

"These fluorescent RNAs offer us a tool that will be critical for understanding the diverse roles that RNA plays in human biology," says the study's senior author, Dr. Samie Jaffrey, an associate professor of pharmacology at Weill Cornell Medical College.

In recent years, the many roles played by RNA have become clearer. "Scientists used to think that RNA's function was limited to making proteins and that these proteins alone dictated everything that happened in cells," he says. "But now we are understanding that cells contain many different forms of RNA -- and some RNAs influence cell signaling and gene expression without ever being used for synthesizing proteins."

The list of known types of RNA has grown rapidly over the past several years -- from messenger RNA that codes for proteins, to diverse "non-coding" RNAs that affect translation and gene expression, and in some cases bind to proteins and regulate their function -- yet little is known about how these RNAs work, the researchers say.

The study's first author, Dr. Jeremy Paige, who conducted the research as a graduate student in pharmacology at Weill Cornell Medical College, adds that the new technology may provide insights into the development of common disorders. "More and more diseases are being linked to misregulation of RNA, but without being able to see the RNA, we can't understand how these processes lead to disease.

"We hope our RNA mimics of GFP open up the road to discovery," he says.

The RNAs developed by the Jaffrey group function like GFP, a natural protein expressed in jellyfish that exhibits a green fluorescence. GFP has enabled scientists to watch how proteins move in cells, providing powerful new insights into their roles in cell function. The DNA that encodes GFP is placed next to a gene that encodes for a protein, resulting in the expression of a protein fused to GFP, which can be observed by specialized forms of microscopy.

To make an RNA that functions like GFP, the Weill Cornell investigators took advantage of the ability of RNA to fold into complex three-dimensional shapes. Their goal was to create two new entities: a synthetic RNA sequence that would adopt a specific shape, and a small molecule that would bind to the new RNA and begin to fluoresce. "These were two huge challenges," says Dr. Jaffrey. "One challenge was to come up with an RNA sequence that could 'switch on' a small molecule. The other big hurdle was to find a small molecule that would fluoresce only when we wanted it to and would not be toxic to cells."

They tried a number of molecules, most of which stuck to oily lipids in the cell membrane and started fluorescing, or they would kill the cell. Finally, the team realized that GFP itself had a molecule, a fluorophore, within it that switched its light on when it was bound in a certain way within the protein. They created chemical molecules based on the shape of this fluorophore and then developed an artificial RNA sequence, or "aptamer," that held the fluorophore in exactly the same way that GFP held its fluorophore. They named this RNA "Spinach" for its bright green fluorescence.

The researchers went even further. They also developed several other RNA-fluorophore pairs, in addition to Spinach, that each emit a different fluorescent color, just as GFP has been evolved to exhibit a palette of colors that helps researchers track many proteins at once. Whereas GFP derivatives are often named after fruits, the Weill Cornell researchers named their RNA mimics of GFP after vegetables -- Spinach, Carrot and Radish.

The Weill Cornell investigators have already begun to use Spinach to track non-coding RNAs in cells. "Our laboratory has been very interested understanding why defects in RNA trafficking and translocation lead to developmental disorders in children, such as mental retardation," says Dr. Jaffrey. Using Spinach, they were able to watch as a non-coding RNA, fluorescing green, rapidly clusters in response to cellular stress. "We expect that Spinach will provide new insights into RNA trafficking in cells, and how this is affected in medical disorders," he says.

"There is still a lot of mystery surrounding RNA in biology. Fluorescent labeling and imaging has proved to be a powerful tool for scientists in the past, and we are hoping that Spinach too will be a tool that helps accelerate scientific discovery," says Dr. Paige.

Dr. Karen Wu of the Department of Pharmacology is a co-author on the study.

The work was supported by the McKnight Neuroscience Technology Innovation Award and the National Institutes of Neurological Disorders and Stroke.

Weill Cornell Medical College has filed a patent application on the technology.

Weill Cornell Medical College
Weill Cornell Medical College, Cornell University's medical school located in New York City, is committed to excellence in research, teaching, patient care and the advancement of the art and science of medicine, locally, nationally and globally. Physicians and scientists of Weill Cornell Medical College are engaged in cutting-edge research from bench to bedside, aimed at unlocking mysteries of the human body in health and sickness and toward developing new treatments and prevention strategies. In its commitment to global health and education, Weill Cornell has a strong presence in places such as Qatar, Tanzania, Haiti, Brazil, Austria and Turkey. Through the historic Weill Cornell Medical College in Qatar, the Medical College is the first in the U.S. to offer its M.D. degree overseas. Weill Cornell is the birthplace of many medical advances -- including the development of the Pap test for cervical cancer, the synthesis of penicillin, the first successful embryo-biopsy pregnancy and birth in the U.S., the first clinical trial of gene therapy for Parkinson's disease, and most recently, the world's first successful use of deep brain stimulation to treat a minimally conscious brain-injured patient. Weill Cornell Medical College is affiliated with NewYork-Presbyterian Hospital, where its faculty provides comprehensive patient care at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. The Medical College is also affiliated with the Methodist Hospital in Houston. For more information, visit weill.cornell.edu.

Andrew Klein | Newswise Science News
Further information:
http://www.cornell.edu

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>