Johns Hopkins researchers found that, in fruit flies, a form of motor neuron disease causes a traffic jam of cellular materials in the neurons’ outer appendages. The scientists learned that the motor neurons – cells that control muscle movement – were unable to transport cargo such as signaling molecules and proteins in need of recycling from the tips of their appendages back to the main hub of the cell.
To study how motor neuron disease affects the body’s neurons, researchers duplicated a genetic change found in patients with an inherited motor neuron disease. The protein affected by the genetic change, p150glued, is a piece of a transporter that delivers materials from the outer reaches of the cell to its central core. Like the people with some types of motor neuron disease, the fruit flies developed progressive paralysis and died early; they also couldn’t fly. The scientists observed that in normal neurons, the cargo moved from one end of the appendages all the way back to the main hub of the cell, but in the defective neurons, the cargo at the very ends of the appendages was stuck there. The cargo along the main appendages moved normally.
“By determining what goes wrong on the cellular level in motor neuron disease, we can begin to develop therapeutics that mitigate these effects to treat the disease,” says Thomas Lloyd, M.D., Ph.D., assistant professor of neurology and neuroscience at the Johns Hopkins University School of Medicine.
Johns Hopkins researchers at American Society of Cell Biology Annual Meeting
Special Interest Subgroup: Dynein
Tuesday, Dec. 18, 2012; Exhibit Halls A-C, 12:30 – 2 p.m.
Authors: J. Machamer, S. Collins, Y. Yang, S. Collins and T. Lloyd
Johns Hopkins Medicine