Testosterone regulates α-synuclein mRNA in the avian song system

alpha -Synuclein is a small, highly conserved protein in vertebrates that has been linked to several neurodegenerative diseases. The avian song control system is one of the model systems in which the protein was independently discovered. alpha -synuclein is dynamically regulated in the song system during song learning, a process in which sex steroids play a central role. We compared alpha -synuclein mRNA expression in the brains of 12 adult male chipping sparrows (Spizella passerina) treated with either testosterone or blank s.c. implants. We saw pronounced upregulation of alpha -synuclein mRNA in, as well as an increase in the volume of, the song control nucleus area X in response to exogenous testosterone. To our knowledge this is the first report of steroid regulation of synuclein gene expression in any model system. NeuroReport 12:943-946 (C) 2001 Lippincott Williams & Wilkins.