Probing astrocyte function in fragile X syndrome.

Astrocytes have been recognized as a class of cells that fill the space between neurons for more than a century. From their humble beginnings in the literature as merely space filling cells, an ever expanding list of functions in the CNS now exceeds the list of functions performed by neurons. In virtually all developmental and pathological conditions in the brain, astrocytes are involved in some capacity that directly affects neuronal function. Today we recognize that astrocytes are involved in the development and function of synaptic communication. Increasing evidence suggests that abnormal synaptic function may be a prominent contributing factor to the learning disability phenotype. With the discovery of FMRP in astrocytes, coupled with a role of astrocytes in synaptic function, research directed to glial neurobiology has never been more important. This chapter highlights the current knowledge of astrocyte function with a focus on their involvement in Fragile X syndrome.