Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify enzyme that turns on RNA

19.09.2002


Knowing an organism’s genome is good, but knowing what turns on its genes is even better.



Scientists have long searched for triggers that activate ribonucleic acid (RNA), a key component in gene expression. Now, in the Thursday, Sept. 19 issue of the journal Nature, scientists from the University of Wisconsin-Madison report that they have found an enzyme that activates RNA, which could lead to new ways of regulating genetic information.

"One of the big questions in molecular biology is how genes are controlled," says Judith Kimble, a Howard Hughes Medical Institute investigator, a UW-Madison professor of biochemistry and senior author of the paper. "Our finding provides an important piece of the puzzle."


Inside the nucleus of every cell are genes, which are composed of deoxyribonucleic acid (DNA). This genetic information contains all the instructions cells need to make proteins, molecules that enable cells to carry out special functions, such as the transport of oxygen by red blood cells. For these cellular activities to happen, DNA must get copied into RNA, which carry the instructions outside the nucleus to the molecular machinery that makes proteins.

But along the way, things can go awry: If an RNA isn’t activated, Kimble says, "it can get trashed or hidden away. And, if the cell doesn’t have a particular RNA, it won’t have any of the protein the RNA encodes."

Liaoteng Wang, lead author of the article and a graduate student in Kimble’s lab, adds, "a gene won’t do any good if it fails to be expressed."

By studying the embryonic development of the microscopic worm, C. elegans, Kimble and Wang, as well as Marvin Wickens and Christian Eckmann also from UW-Madison’s biochemistry department, identified two proteins - GLD-2 and GLD-3 - that, when bound together to form an enzyme, activate specific RNAs outside the nucleus. This activation would enable the RNA to carry out important steps of germ line, or reproductive, development, such as the formation of sperm or egg cells. In other words, RNA wouldn’t get "trashed."

"People had been looking for this enzyme for a long time," says Kimble. "We were incredibly lucky. We found it serendipitously."

As Kimble explains, Wang and Eckmann had been working independently on the different proteins, both of which are responsible for most stages of germ line development. Wang studied GLD-2 and found that it had a site where reactions could take place, but that it couldn’t bind to an RNA. Eckmann, who studied GLD-3, found that his protein could do just the opposite: it could bind to an RNA, but didn’t have the catalytic site.

"Wang and Eckmann started looking for binding partners for their individual proteins and, amazingly, they found that GLD-2 and GLD-3 bound to each other," says Kimble.

Binding the two proteins together created an enzyme that could not only attach itself to RNA but could also chemically modify the RNA in a specific way that turns it on. And, as Kimble says, "When regulating biologic processes, you don’t want to activate all the RNAs in a cell - you want to activate only the important RNAs at the right time and in the right place."

Researchers have found homologs, or proteins similar to GLD-2, in other organisms, ranging from yeast to humans. Little is known about these homologs, except their amino acid sequences, says Kimble. Proteins similar to GLD-3 have also been found, but only in more complex animals, ranging from worms to humans. Again, how these proteins work remains a mystery.

"More and more organisms’ genomes have been completely sequenced, but sequences don’t tell you the biochemical function of proteins," says Wang. "In this study, we identified the biochemical function of GLD-2, and, since there are proteins in other organisms that have sequences similar to this protein, we can now make more educated guesses about the function of those proteins. It is the idea of ’one stone, many birds.’"

By identifying this enzyme that regulates how genes are expressed in C. elegans, the researchers say it will now be possible for scientists to explore how similar enzymes work in humans, possibly one day leading to new therapies. Says Kimble, "I think this is a big finding for anyone interested in how genes are regulated."


Emily Carlson (608) 262-9772, emilycarlson@facstaff.wisc.edu

Judith Kimble | EurekAlert!

More articles from Life Sciences:

nachricht MicroRNA helps cancer evade immune system
19.09.2017 | Salk Institute

nachricht Ruby: Jacobs University scientists are collaborating in the development of a new type of chocolate
18.09.2017 | Jacobs University Bremen gGmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

Im Focus: Artificial Enzymes for Hydrogen Conversion

Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.

Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

New quantum phenomena in graphene superlattices

19.09.2017 | Physics and Astronomy

A simple additive to improve film quality

19.09.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>