A team of scientists, including faculty at the University of Massachusetts Medical School (UMMS), have discovered a gene that influences survival time in amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's disease).
The study, published today in Nature Medicine, describes how the loss of activity of a receptor called EphA4 substantially extends the lifespan of people with the disease. When coupled with a UMMS study published last month in Nature identifying a new ALS gene (profilin-1) that also works in conjunction with EphA4, these findings point to a new molecular pathway in neurons that is directly related to ALS susceptibility and severity.
"Taken together, these findings are particularly exciting because they suggest that suppression of EphA4 may be a new way to treat ALS," said Robert Brown, MD, DPhil, a co-author on the study and chair of neurology at UMass Medical School.
ALS is a progressive, neurodegenerative disorder affecting the motor neurons in the central nervous system. As motor neurons die, the brain's ability to send signals to the body's muscles is compromised. This leads to loss of voluntary muscle movement, paralysis and eventually respiratory failure. The cause of most cases of ALS is not known. Approximately 10 percent of cases are inherited. Though investigators at UMMS and elsewhere have identified several genes shown to cause inherited or familial ALS, almost 50 percent of these cases have an unknown genetic cause. There are no significant treatments for the disease.
Wim Robberecht, MD, PhD, lead investigator of the Nature Medicine study and a researcher at the University of Leuven in Belgium and the Vesalius Research Center, screened for genes in zebrafish that blunt the adverse effect of the ALS mutant gene SOD1. Through this process, his team identified EphA4 as an ALS modifier. Dr. Robberecht's team went on to show that when this gene is inactivated in mice with ALS, the mice live longer.
Dr. Robberecht then turned to UMass Medical School to confirm that turning off EphA4 in human ALS cells would slow the progression of the disease. Dr. Brown and his team identified two human ALS cases with mutations in the EphA4 gene which, like the zebrafish and the mice, had unusually long survival times. This suggests that blocking EphA4 in patients with ALS may be a potential therapeutic target in the future.
In an exciting, related development, a new ALS gene (profilin-1) identified last month by UMMS scientists works in conjunction with EphA4 in neurons to control outgrowth of motor nerve terminals. In effect, gene variants at both the top and the bottom of the same signaling pathway are shown to effect ALS progression. Together these discoveries highlight a new molecular pathway in neurons that is directly related to ALS susceptibility and severity and suggests that other components of the pathway may be implicated in ALS."It is exciting that these two studies identify the same pathway in ALS," said John Landers, PhD, associate professor of neurology and lead author of the PFN1 study. "Hopefully this discovery will accelerate efforts to finding a treatment for ALS."
Forthcoming Nature Medicine Paper: Van Hoecke A, Schoonaert L, Lemmens R, Timmers M, Staats KA, Laird AS, Peeters E, Philips T, Goris A, Dubois B, Andersen P, Al-Chalabi A, Thijs V, Turnley AM, van Vught PW, Veldink JH, Van Den Bosch L, Gonzalez-Perez P, Van Damme P, Brown RH Jr, van den Berg LH, Robberecht W. Genetic screening in zebrafish identifies EphA4 of the ephrin axonal repellent system as a disease modifier of amyotrophic lateral sclerosis in rodent models and patients. In press, Nat Medicine.
Profilin1 Paper: Wu C-H, Fallini C, Ticozzi N, Keagle PJ, Sapp PC, Piotrowska K, Lowe P, Koppers M, McKenna-Yasek D, Baron D, Kost E, Gonzalez-Perez P, Fox AD, Adams J, Taroni F, Tiloca C, Leclerc AL, Chafe SC, Mangroo D, Moore MJ, Zitzewitz J, Xu Z-S, van den Berg LH, Glass JD, Siciliano G, Cirulli ET, Goldstein DB, Salachas F, Meninger V, Rossoll W, Ratti A, Gellera C, Bosco DA, Bassell GJ, Silani V, Drory VE, Brown RH Jr., Landers JE. Mutations in the profilin 1 gene cause familial amyotrophic lateral sclerosis. Nature. 2012 Jul 15
Jim Fessenden | EurekAlert!
Modern genetic sequencing tools give clearer picture of how corals are related
17.08.2017 | University of Washington
The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
17.08.2017 | Physics and Astronomy
17.08.2017 | Earth Sciences
17.08.2017 | Physics and Astronomy