Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Jefferson scientists identify a new protein involved in longevity

10.05.2010
Researchers in the Department of Biochemistry and Molecular Biology at Thomas Jefferson University have found that the level of a single protein in the tiny roundworm C. elegans determines how long it lives. Worms born without this protein, called arrestin, lived about one-third longer than normal, while worms that had triple the amount of arrestin lived one-third less.

The research also showed that arrestin interacts with several other proteins within cells to regulate longevity. The human version of one of these proteins is PTEN, a well-known tumor suppressor. The study, to be published in the online edition of the Journal of Biological Chemistry, was chosen by the journal as the "Paper of the Week" – considered in the top one percent of published articles.

Because most proteins in worms have human counterparts, these findings may have relevance to human biology and the understanding of cancer development, said Jeffrey L. Benovic, Ph.D., professor and chair of the department.

"The links we have found in worms suggest the same kind of interactions occur in mammals although human biology is certainly more complicated. We have much work to do to sort out these pathways, but that is our goal," said Dr. Benovic.

Researchers use the roundworm as a model because it offers a simple system to study the function of genes and proteins that are relevant to human biology. The worm, for example, has one arrestin gene, whereas humans have four. Worms only have 302 neurons compared to the 100 billion or so in the human brain. In addition, their short lifespan of two to three weeks allows for timely observation of effects on longevity.

Dr. Benovic and the study's first author, Aimee Palmitessa, Ph.D., a postdoctoral research fellow, studied signaling pathways activated by G protein-coupled receptors. These receptors bind to all kinds of hormones, sensory stimuli (such as light, odorants and tastants), neurotransmitters, etc., which then activate a cascade of signals inside the cell. They regulate many physiological processes and are the target for about half of the drugs currently on the market.

"When it comes to receptors, worms are actually more complex," said Dr. Benovic. "Humans have about 800 different kinds of G protein-coupled receptors while the worm has about 1,800. It relies upon these receptors to respond to sensory stimuli as well as various neurotransmitters and hormones."

Arrestins were initially found to turn off the activation of G protein-coupled receptors inside cells. "Their name comes from the fact that they arrest the activity of receptors, so the worm offers a good way to study how its single arrestin protein interacts with protein receptors," says Dr. Benovic. Two of the four arrestins that humans have are devoted to regulating receptors that respond to visual stimuli while the other two regulate most other receptors.

In this study, Dr. Palmitessa deleted the single arrestin gene in worms to see what would happen, and found, to her surprise, that these worms lived significantly longer. She also found that over-expressing arrestin in worms shortened their lifespan. "A little less arrestin is good – at least for worms," Dr. Benovic reported.

This isn't the first discovery made regarding longevity in worms. Researchers have already found that activity of the insulin-like growth factor-1 (IGF-1) receptor can influence longevity in worms – a finding that has also been replicated in fruit flies, mice, and humans. Like arrestin, a little less IGF-1 receptor activity is good, Dr. Benovic explained. Further research has shown that caloric restriction can also reduce IGF-1 receptor activation and, conversely, over-expression of the IGF-1 receptor is found in some human cancers.

In this study, Dr. Benovic and Dr. Palmitessa dug a little deeper and found that in the worms, arrestin interacted with two other proteins that play a critical role in its ability to regulate longevity. One of those proteins is the tumor suppressor PTEN; mutations in PTEN are involved in a number of different cancers.

Dr. Benovic said the connection between human arrestin and PTEN is not clear. "We don't know at this point if human arrestins regulate PTEN function or if anything happens to arrestin levels during the development of cancer," he said. "Do increasing levels turn off more PTEN, thus promoting cancer, or do levels decrease and allow PTEN to be more active?

"If it turns out to be the first scenario – that increasing amounts of arrestin turn off the tumor suppressor activity of PTEN, then it may be possible to selectively inhibit that process," he says. "We have some interesting work ahead."

The study was funded in part by the National Institutes of Health. The authors declare no conflict of interest.

Emily Shafer | EurekAlert!
Further information:
http://www.jefferson.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | 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

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>