Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers develop new way to see single RNA molecules inside living cells

08.04.2009
Biomedical engineers have developed a new type of probe that allows them to visualize single ribonucleic acid (RNA) molecules within live cells more easily than existing methods. The tool will help scientists learn more about how RNA operates within living cells.

Techniques scientists currently use to image these transporters of genetic information within cells have several drawbacks, including the need for synthetic RNA or a large number of fluorescent molecules. The fluorescent probes developed at the Georgia Institute of Technology circumvent these issues.

"The probes we designed shine bright, are small and easy to assemble, bind rapidly to their targets, and can be imaged for hours. These characteristics make them a great choice for studying the movement and location of RNA inside a single cell and the interaction between RNA and binding proteins," said Philip Santangelo, an assistant professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University.

Details of the probe production process and RNA imaging strategy were published online in the journal Nature Methods on April 6. In addition to Santangelo, Georgia Tech graduate student Aaron Lifland, Emory University associate professor Gary Bassell and Vanderbilt University professor James Crowe Jr. also contributed to this research. This research was funded by new faculty support from Georgia Tech.

In the study, the probes – produced by attaching a few small fluorescent molecules called fluorophores to a modified nucleic acid sequence and combining the sequences with a protein – exhibited single-molecule sensitivity and allowed the researchers to target and follow native RNA and non-engineered viral RNA in living cells.

"The great thing about these probes is that they recognize RNA sequences and bind to them using the same base pairing most people are familiar with in regards to DNA," explained Santangelo. "By adding only a few probes that would bind to a region of RNA, we gained the ability to distinguish a targeted RNA molecule from a single unbound probe because the former lit up two or three times brighter."

For their experiments, the team used a bacterial toxin to transport the probes into living cells – a delivery technique that when combined with the high affinity of the probes for their targets, required significantly fewer probes than existing techniques. The toxin created several tiny holes in the cell membrane that allowed the probes to enter the cell's cytoplasm.

The researchers tested the sensitivity of conventional fluorescence microscopy to image individual probes inside a cell. Previous studies showed that these techniques were able to image an accumulation of probes inside a cell, but the current study demonstrated that individual probes without cellular targets could be observed homogenously distributed in the cytoplasm with no localization or aggregation.

With single-molecule sensitivity accomplished, the researchers investigated whether they could visualize individual RNA molecules using the probes. To do this, they simultaneously delivered probes designed to target a human messenger RNA (mRNA) sequence region and a probe designed with no target in the human genome. They were able to image unbound probes of both types as well as individual RNA molecules that had attached to the former probes.

The imaging technique also allowed the researchers to observe a process called dynamic RNA-protein co-localization, which is the joining of RNA molecules and RNA binding proteins in a single cell.

"We observed substantial transient interactions between proteins and viral RNA molecules that I don't think had ever been seen before with non-engineered RNA," noted Santangelo. "We saw one of the proteins move into a viral RNA granule and reside within it for over a minute before it was released, and we also saw another protein that appeared to dock with a viral RNA granule."

Santangelo is currently trying to improve the probes by making them smaller and brighter, while also using them to investigate viral pathogenesis and other biological phenomena.

"We are excited to use this imaging strategy to study how single viral RNAs travel from the nucleus of a cell to a virus assembly site, how mRNAs are regulated by location and time, and RNA trafficking in neurons," added Santangelo.

Abby Vogel | EurekAlert!
Further information:
http://www.gatech.edu

More articles from Life Sciences:

nachricht Designer cells: artificial enzyme can activate a gene switch
22.05.2018 | Universität Basel

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>