Following a major Northwestern Medicine breakthrough that identified a common converging point for all forms of amyotrophic lateral sclerosis (ALS and Lou Gehrig's disease), a new finding from the same scientists further broadens the understanding of why cells in the brain and spinal cord degenerate in the fatal disease.
Less than three months ago, Northwestern research found that the crucial recycling system for cells in the brain and spinal cord was broken in people with ALS. And one mutated gene had a key role. Like a loafing worker, it wasn't doing its job to recycle damaged cells.
Now, scientists have discovered a second faulty gene -- a new loafing worker -- in the same recycling pathway. The finding is reported in Archives of Neurology.
"Now that we have two bad players, it shines more light on this broken pathway," said senior author Teepu Siddique, M.D., the Les Turner ALS Foundation/Herbert C. Wenske Professor of the Davee Department of Neurology and Clinical Neurosciences at Northwestern's Feinberg School and a neurologist at Northwestern Memorial Hospital. "This gives us a clear target to develop drug therapies to try to fix this problem. It strengthens our belief that this broken system is at the heart of ALS."
The new "bad player" is called sequestosome1. The previously identified mutated gene is ubiquilin2. Because these two genes aren't doing their jobs to recycle damaged proteins, those proteins – as well as sequestosome1 and ubiquilin2 -- accumulate abnormally in the motor neurons in the spinal cord and cortical and hippocampal neurons in the brain. The protein accumulations resemble twisted skeins of yarn -- characteristic of ALS -- and cause the degeneration of the neurons.
In the new study, sequestosome1 genetic mutations were identified in 546 ALS patients; 340 with an inherited form of the disease, called familial, and 206 with a non-inherited form of the disease, called sporadic.
About 90 percent of ALS is sporadic and 10 percent is familial. To date, mutations in about 10 genes, several of which were discovered at Northwestern, including SOD1 and ALSIN, account for about 30 percent of classic familial ALS, noted Faisal Fecto, M.D., study lead author and a PhD candidate in neuroscience at Feinberg.
ALS affects an estimated 350,000 people worldwide, including children and adults, with about 50 percent of people dying within three years of its onset. In the motor disease, people progressively lose muscle strength until they become paralyzed and can no longer move, speak, swallow and breathe. ALS/dementia targets the frontal and temporal lobes of the brain, affecting patients' judgment, the ability to understand language and to perform basic tasks like planning what to wear or organizing their day.
The discovery of the breakdown in protein recycling may also have a wider role in other neurodegenerative diseases, particularly the dementias. These include Alzheimer's disease and frontotemporal dementia as well as Parkinson's disease, all of which are characterized by aggregations of proteins, Siddique said. The removal of damaged or misfolded proteins is critical for optimal cell functioning, he noted.
The study was supported by the National Institute of Neurological Disorders and Stroke, the Les Turner ALS Foundation, the Herbert and Florence C. Wenske Foundation and other sources.
Marla Paul | EurekAlert!
Turning carbon dioxide into liquid fuel
06.08.2020 | DOE/Argonne National Laboratory
Tellurium makes the difference
06.08.2020 | Friedrich-Schiller-Universität Jena
Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.
Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...
An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.
Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...
Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...
“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.
Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...
An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.
Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...
23.07.2020 | Event News
21.07.2020 | Event News
07.07.2020 | Event News
06.08.2020 | Earth Sciences
06.08.2020 | Power and Electrical Engineering
06.08.2020 | Life Sciences