Genetic Mutation Affecting Proteins Could Cause ALS
Over 5,000 people are diagnosed with ALS each year in the United States. Amyotrophic Lateral Sclerosis is a disease that attacks the very roots of human biology. Over time, patients with this condition lose muscle function which can end up being fatal. The million dollar question is, what causes the loss of this muscle movement? Our bodies are made up of trillions of individual cells and within those cells there are millions of proteins. These proteins truly run the show! Although there is no known cause for ALS, research points to protein mishandling as a major perpetrator. Researchers ask themselves how to stop these misfolding proteins.
“We mapped out the process by which UBQLN2 gene mutations disrupt an important recycling pathway that cells use to get rid of their trash,” said Mervyn Monteiro, PhD, Professor of Anatomy and Neurobiology, at the University of Maryland School of Medicine, a senior author of the study.
International researchers are diving deeper into the gene coding ubiquilin-2 (UBQLN2) which can stop the body from discarding misfolding proteins that build up in the body and destroy nerve cells. The team studied both human and mouse models and compared cells with the UBQLN2 with normal cells. They found that the cells with the mutation were not getting rid of the dysfunctioning proteins or parts of the cells or tissues properly, a process known as 'autophagy'. The protein ATP6v1g1 which is needed for the cellular breakdown process in order to regulate acidification, was too low.
“Without this recycling, misfolded proteins build up in the nerve cell and become toxic, eventually destroying the cell.” Monteiro explains.
The team found that over expressing the ATP6v1g1 protein in the cell line that had lost UBQLN2 function could start-up the autophagy process again, suggesting a possible treatment method for people with UBQLN2-linked ALS.
“This suggests that restoration of the defect could have broad implications for not only treating ALS, but possibly other neurodegenerative diseases as well.” Monteiro states.