Mayo Clinic Researchers Find Unexpected Discovery, Which Could Indicate New Target for ALS Therapy
Published: Feb 12, 2013
ALS, which is also known as Lou Gehrig's Disease, is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. Eventually, people with ALS lose the ability to initiate and control muscle movement, which often leads to total paralysis and death within two to five years of diagnosis. There is no cure, and only one drug approved by the U.S. Food and Drug Administration (FDA) modestly extends survival.
The study, conducted by Peter Ash and Kevin Bieniek under the guidance of Leonard Petrucelli, Ph.D., of the Mayo Clinic in Jacksonville, Fla., showed that mutations in the C9ORF72 gene cause cells to create an unusual protein-like molecule that is not found in healthy individuals or in people with other neurologic diseases. Mutations in the C9ORF72 gene are responsible for between 20 percent and 40 percent of familial ALS. The mutation causes cells to create long, repetitive chains of a cellular molecule called RNA.
The researchers found that when the cell's protein-making machinery latches on to this repetitive RNA, it creates a protein-like chain called a RAN-translated peptide, which the researchers have termed C9RANT. The peptide's own repetitive structure makes it stick to itself, and the researchers found clumps of the peptide in the brains of people who had died of ALS.
It is still unknown whether these peptides are contributing to disease or are uninvolved in it. But in either case, they offer researchers a specific marker for ALS caused by the C9ORF72 gene and potentially a way to measure disease activity and response to therapy.
"This discovery highlights the complexity of the ALS disease process," said ALS Association Chief Scientist Lucie Bruijn, Ph.D. "But it also may provide a new window into that process and offer a way to track how neurons are responding to treatments in this form of the disease. In that respect, this finding could be an important step forward."
"Just as new therapies are being developed to break down the protein aggregates associated with Alzheimer's and Parkinson's diseases, developing a therapeutic strategy to target C9RANT aggregates may also prove beneficial," said Dr. Petrucelli, Chair of Neuroscience.
The ALS Association provided support for this research through its Translational Research Advancing Therapies for ALS (TREAT ALS) program, to Dr. Petrucelli and to Kevin Boylan, M.D., also of the Mayo Clinic and also an author in this study.
About The ALS Association
The ALS Association is the only national non-profit organization fighting Lou Gehrig's Disease on every front. By leading the way in global research, providing assistance for people with ALS through a nationwide network of chapters, coordinating multidisciplinary care through certified clinical care centers, and fostering government partnerships, The Association builds hope and enhances quality of life while aggressively searching for new treatments and a cure. For more information about The ALS Association, visit our website at www.alsa.org.
SOURCE The ALS Association
Carrie Martin Munk, The ALS Association, email@example.com,