Tau, a microtubule-associated protein, is encoded by a single gene, the expression of which is neuron-specific and developmentally regulated. When PC12 cells are exposed to nerve growth factor (NGF), they differentiate to sympathetic-like neurons. This differentiation process is accompanied by an elevation of tau proteins and mRNA. Here, we describe, for the first time, the isolation and characterization of a tau promoter region. We show that the promoter of tau is G + C-rich, lacks a genuine TATA box and thus promotes multiple initiation sites of RNA transcription. Our results demonstrate that a region of approximately 335 base-pairs residing immediately upstream of tau exon -1 are able to direct positive control of neuron-specific activity of the luciferase reporter gene. The isolation of tau promoter will facilitate facilitate further studies of the regulation of tau expression during development and aging of neuronal cells.