To identify gigaxonin's role, scientists used cells known as fibroblasts obtained from skin biopsies of children with GAN. The cells were then grown in lab cultures, and they also contained large abnormal aggregates of intermediate filaments. When scientists introduced healthy gigaxonin genes into both control and patient fibroblasts, the results were dramatic. The abnormal aggregates of intermediate filaments disappeared. However, the cytoskeleton's two other major systems, microtubules and actin filaments were not affected by this treatment.
The study's lead author, Northwestern University postdoctoral fellow Saleemulla Mahammad, stressed that this discovery may also have implications for more common types of neurodegenerative diseases that are also characterized by large accumulations of intermediate filament proteins, including Alzheimer's disease and Parkinson's disease.
"Our results suggest new pathways for disease intervention," he said. "Finding a chemical component that can clear the intermediate filament aggregations and restore the normal distribution of intermediate filaments in cells could one day lead to a therapeutic agent for many neurological disorders."
Mahammad and other members of the Goldman Laboratory collaborated with Puneet Opal, M.D., associate professor in the Ken and Ruth Davee department of neurology and cell and molecular biology, along with researchers in the laboratory of Pascale Bomont, at the INSERM neurological institute in Montpelier, France, and the laboratory of Jean-Pierre Julien at the Universit Laval in Quebec, Canada.
|Contact: Marla Paul|