Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gladstone scientists discover gene 'bursting' plays key role in protein production

09.10.2012
Findings question earlier studies and shed light on fundamental cellular process

Scientists at the Gladstone Institutes have mapped the precise frequency by which genes get turned on across the human genome, providing new insight into the most fundamental of cellular processes—and revealing new clues as to what happens when this process goes awry.

In a study being published this week online in the Proceedings of the National Academy of Sciences, Gladstone Investigator Leor Weinberger, PhD, and his research team describe how a gene's on-and-off switching—called "bursting"—is the predominant method by which genes make proteins.

By gaining an understanding of this underlying mechanism, this discovery has the potential to vastly help researchers learn what happens at the molecular level when this mechanism is disrupted—such as in cancer or when exposed to a particular drug.

The manufacture, or synthesis, of proteins takes place inside every cell. DNA and genes—which house the instructions for making proteins—are stored within the nucleus of each cell. When a gene is switched on, those instructions are transcribed as a copy onto RNA, another type of genetic material that then directs the protein synthesis. Proteins perform a variety of functions within the cell—from the breaking down and digesting fats to resisting foreign invaders, such as bacteria or viruses. The timing and frequency with which a particular protein is synthesized is crucial to maintaining the health of the cell.

"Much like flicking on a light switch, genes get 'switched on' at specific intervals to initiate the fundamental biological process of protein synthesis," said Dr. Weinberger, who is also an associate professor at the University of California, San Francisco (UCSF), with which Gladstone is affiliated. "Until recently, the process was thought to be continuous—once a gene is switched on, it stays on, churning out protein products at a steady pace like a garden hose. But recently, some studies have suggested the opposite—that DNA produces RNA molecules in rapid-fire 'staccato' bursts. We decided to investigate how common this rapid-fire bursting was across the genome."

In laboratory experiments, Dr. Weinberger and his team inserted a green fluorescent protein, or "vector," into the DNA of Jurkat T lymphocytes—a type of white blood cell that helps maintain a healthy human immune system. From this they generated new cells in which the vector was integrated into any one of thousands of gene segments—with each segment glowing green when it was activated, or "switched on." This allowed the researchers to see exactly how gene activation occurred across the entire human genome.

"Our analysis reveals support for the "bursting" hypothesis—the genes acted as a sort of strobe light—transcribing RNA in rapid-fire bursts," said Roy Dar, PhD, a Gladstone postdoctoral fellow and one of the paper's lead authors. "We observed that the bursting frequency increases until, over time, it reaches a particular threshold. At that point higher protein levels are reached by increasing the size of the bursts, eventually coming to a halt when no more protein product is needed. These results are a huge step towards understanding the basic molecular mechanism behind gene regulation."

"Dr. Weinberger and colleagues have shown that there is a single rule governing the behavior of all genes in the genome. Their findings in human cells complement and extend similar findings made recently in other organisms," said Arjun Raj, PhD, assistant professor of bioengineering at the University of Pennsylvania and an expert in imaging single molecules within cells.

The team believes that this new-found understanding of this fundamental biological process—that genomic bursts account for the majority of instances of protein production—holds clues to discovering how the disruption of these bursts could be harmful.

"For example, in certain cancers, genes may be switched on at the wrong times, eventually leading to the formation of tumors," said Brandon Razooky, a Gladstone and UCSF graduate student and the paper's other lead author. "This is also a good example of how the basic science being performed here at Gladstone provides a solid foundation with which to prevent, treat and ultimately cure some of the world's most devastating diseases."

Michael Simpson, PhD, from the Oak Ridge National Laboratory Center for Nanophase Materials Sciences, is also a senior author on this paper. Funding came from a variety of sources, including the NIH Director's Common Fund Program (through the NIH Director's New Innovator Award Program), the National Science Foundation's Graduate Research Fellowship Program, the US Department of Energy, the Pew Scholars Program in the Biomedical Sciences, and the Alfred P. Sloan Foundation

About the Gladstone Institutes Gladstone is an independent and nonprofit biomedical-research organization dedicated to accelerating the pace of scientific discovery and innovation to prevent, treat and cure cardiovascular, viral and neurological diseases. Gladstone is affiliated with the University of California, San Francisco.

Anne Holden | EurekAlert!
Further information:
http://www.gladstone.ucsf.edu

More articles from Life Sciences:

nachricht Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

nachricht Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>