Glutamate regulates dystrophin-71 levels in glia cells.

Glial glutamate receptors are likely to be involved in neuronal differentiation, migration, and plasticity. Dystrophin, the protein defective in Duchenne muscular dystrophy (DMD) is widely expressed in the Central Nervous System. Activation of internal promoters of the DMD gene leads to the production of several proteins, the Dystrophin-71 (Dp-71) being the most abundant in the encephalon. This protein is known to stabilize neurotransmitter receptors in clusters and its absence has been correlated with cognitive deficits in a mouse model. Using cultured chick Bergmann glia cells and mouse cerebellar fusiform astrocytes, we demonstrate here that glutamate receptor activation results in a time and dose dependent decrease of Dp-71 levels. This effect is mediated through alphaamino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. The present results suggest an involvement of Dp-71 in glutamate receptor signaling and possibly clustering and further support the notion of an active role of glia in the physiology of glutamatergic transmission.