FSU researchers make observing cell functions easier

May 8, 2008
FSU researchers make observing cell functions easier
This image illustrates fluorescence resonance energy transfer works. With FRET, the illuminated yellow molecules come together, signaling that they are transferring energy in the living cell. Credit: Courtesy of Michael Davidson, National High Magnetic Laboratory

Now that the genome (DNA) of humans and many other organisms have been sequenced, biologists are turning their attention to discovering how the many thousands of structural and control genes -- the “worker bees” of living cells that can turn genes on and off -- function.

To do that, they need to develop new techniques and tools. Scientists in the Optical Microscopy group at the National High Magnetic Field Laboratory at Florida State University, working in collaboration with researchers from the University of Alberta in Canada and the University of California, San Diego, have done just that, and in the process have produced back-to-back articles in the prestigious journal Nature Methods.

In the first paper, magnet-lab biologists Michael Davidson and Kristen Hazelwood worked with researchers from the University of Alberta to create two new fluorescent-protein biosensors, molecular “beacons” that can tell if there is activity within a cell. The biosensors can be used simultaneously to monitor two separate dynamic functions in a single cell -- a key to understanding how different proteins and enzymes (the biomolecules that cause chemical reactions) work together to complete the daily chores that help cells grow and divide. Knowing how cells work together can help researchers learn a great deal more about tumors and developmental biology, among many other things.

The researchers improved a powerful technique used to monitor cellular dynamics called fluorescence resonance energy transfer, or FRET. The technique is used to examine a new class of biosensor molecules that tether two fluorescent proteins together through an intervening peptide (which is like a polymer). Several hundred of these new biosensors have been developed over the past few years and are being used by scientists around the world to study a variety of functions, including programmed cell death, carbohydrate metabolism, cell division, hormone stimulation, acidity changes -- just about any cellular process that can occur.

“In FRET, two molecules that are fluorescent act as ‘molecular beacons’ under the microscope, transferring energy between each other if they interact in the living cell,” said Davidson, who directs the magnet lab’s Optical Microscopy program. “With FRET, we can see that happen, but until now, we have only been able to monitor one biosensor at a time.”

The new technique, called Dual FRET, is outlined in the paper “Fluorescent Protein FRET Pairs for Ratiometric Imaging of Dual Biosensors.” www.nature.com/nmeth/journal/v5/n5/abs/nmeth.1207.html>

Further expanding the capabilities of optical microscopy, Davidson and his team worked with collaborators from the University of California, San Diego to create a new screening method for fluorescent proteins that makes them more stable under the microscope. These proteins are sensitive to light, which can bleach them out after a certain period of time. By making the proteins more stable, microscopists can observe live cell dynamics for longer periods of time. The paper describing their work, “Improving the Photostability of Bright Monomeric Orange and Red Fluorescent Proteins,” was published in the May 4 online edition of Nature Methods. www.nature.com/nmeth/journal/v4/n9/full/nmeth1083.html>

Taken together, the new technique and tool are expected to speed up experiments and expand the utility of optical microscopy by allowing two dynamic processes inside a cell to be observed at once -- and for longer periods of time.

Source: Florida State University

Explore further: Researchers study cellular processes dependent on calcium ions

Related Stories

The skinny on lipid immunology

October 20, 2017

Phospholipids - fat molecules that form the membranes found around cells - make up almost half of the dry weight of cells, but when it comes to autoimmune diseases, their role has largely been overlooked. Recent research ...

Enhancing solar power with diatoms

October 20, 2017

Diatoms, a kind of algae that reproduces prodigiously, have been called "the jewels of the sea" for their ability to manipulate light. Now, researchers hope to harness that property to boost solar technology.

Recommended for you

Two teams independently test Tomonaga–Luttinger theory

October 20, 2017

(Phys.org)—Two teams of researchers working independently of one another have found ways to test aspects of the Tomonaga–Luttinger theory that describes interacting quantum particles in 1-D ensembles in a Tomonaga–Luttinger ...

Using optical chaos to control the momentum of light

October 19, 2017

Integrated photonic circuits, which rely on light rather than electrons to move information, promise to revolutionize communications, sensing and data processing. But controlling and moving light poses serious challenges. ...

Black butterfly wings offer a model for better solar cells

October 19, 2017

(Phys.org)—A team of researchers with California Institute of Technology and the Karlsruh Institute of Technology has improved the efficiency of thin film solar cells by mimicking the architecture of rose butterfly wings. ...

Terahertz spectroscopy goes nano

October 19, 2017

Brown University researchers have demonstrated a way to bring a powerful form of spectroscopy—a technique used to study a wide variety of materials—into the nano-world.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.