Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Muscling toward a longer life: Genetic aging pathway identified in flies

18.10.2011
Researchers at Emory University School of Medicine have identified a set of genes that act in muscles to modulate aging and resistance to stress in fruit flies.

Scientists have previously found mutations that extend fruit fly lifespan, but this group of genes is distinct because it acts specifically in muscles. The findings could help doctors better understand and treat muscle degeneration in human aging.

The results were published online this week by the journal Developmental Cell.

The senior author is Subhabrata Sanyal, PhD, assistant professor of cell biology at Emory University School of Medicine. The first author of the paper is postdoc Alysia Vrailas-Mortimer. Collaborators from Howard University and the University of Athens contributed to the paper.

Vrailas-Mortimer, Sanyal and colleagues started investigating a pair of genes called "p38 MAP kinase" in fruit flies with the expectation that they could play a role in learning and memory. Along the way, they discovered that mutations in these genes speed up the process of aging and make the flies more sensitive to oxidative stress.

"It was really just dumb luck, because we found a mutant that had almost completely lost gene activity, but had enough activity to be born," Sanyal says.

If both genes are defective in the same fly, the flies die very early. They begin to develop motor problems, becoming unable to fly and climb, a few days after birth. The mutant flies are also more sensitive to heat, being deprived of food and water, and exposure to oxidative stress. The researchers could correct the effects of the mutations by restoring the genes' activity in muscles, but not nerve cells.

"The experiment that made us nervous was when we asked whether having more p38 could increase lifespan," Sanyal says. "You can make flies sick and shorten their lives in a hundred different ways easily, but finding one gene that makes a big change in lifespan is more significant."

Fruit flies normally live about fifty days in Sanyal's laboratory, depending on temperature and conditions. Some strains of fly that overproduce p38 MAP kinase live on average about 75 days, 50 percent longer than regular flies (green line in graph below). For this effect, it is sufficient that p38 is overproduced in muscles only.

Vrailas-Mortimer showed that a protein that protects cells against oxidative stress that is found in mitochondria, superoxide dismutase (MnSOD), is responsible for at least some of p38 MAP kinase's effects on aging. A third gene called MEF2 is also involved, in between p38 MAP kinase and MnSOD. Mitochondria are cells' miniature power plants and are more abundant in muscle.

Giving flies more MnSOD can restore a more normal lifespan to the p38 mutants. Other types of antioxidant enzymes don't rescue lifespan in flies with p38 mutations, the researchers found.

P38, MEF2 and MnSOD's action in muscles distinguishes them from a well-studied genetic circuit regulating aging in the worm C. elegans as well as flies and mice, which appears to work through insulin-like hormone responses in the brain and other tissues. Caloric restriction (consistently eating less), an established way of lengthening lifespan, acts through this insulin-like signaling pathway.

"It may be that oxidative stress is especially important in flies' muscles because flies' energy use is so high," Sanyal says. "The role oxidative stress plays in aging is well-known, so its involvement here was not a surprise. I think what's new here is finding a genetic pathway regulating aging that is specific to muscles and separate from insulin signaling."

Sanyal says he and his team plan to examine what kinds of dietary antioxidants can extend lifespan in flies without p38. They also plan to probe how caloric restriction interacts with p38 deficiency.

The research was supported by the National Institutes of Health and Emory's University Research Committee.

Reference:

A. Vrailas-Mortimer et al. A muscle-specific p38 MAPK/Mef2/MnSOD pathway regulates stress, motor function and lifespan in Drosophila. Dev Cell 21, 783-795 (2011).

Holly Korschun | EurekAlert!
Further information:
http://www.emory.edu

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>