• Microtubule-associated protein τ;
  • 5′-Untranslated region;
  • Homogeneous initiation sites;
  • Promoter mapping;
  • Specificity of expression

Abstract: The microtubule-associated protein τ is produced from a 6-kb mRNA expressed primarily in neurons. A 2-kb τ mRNA has also been characterized, which produces a τ isoform that localizes to the nucleus, and an 8-kb mRNA is expressed in the PNS. Mapping and sequencing of the human τ gene start showed that it has an unusually GC-rich 5′-untranslated region coded by a single untranslated exon (designated −1). Primer extensions and expression assays indicated that upstream of exon −1 is a promoter that is not neuron specific. This region contains consensus binding sites for transcription factors AP2, Sp1, and GCF.