A proximal E-box modulates NGF effects on rat PPT-A promoter activity in cultured dorsal root ganglia neurones

Neuropeptides. 2005 Oct;39(5):475-83. doi: 10.1016/j.npep.2005.08.004. Epub 2005 Sep 29.

Abstract

The rat preprotachykinin A (rtPPTA) promoter fragment spanning -865+92, relative to the major transcriptional start, has previously been demonstrated to be nerve growth factor (NGF) responsive in primary cultures of rat dorsal root ganglion (DRG) neurones [Harrison, P.T., Dalziel, R.G., Ditchfield, N.A., Quinn, J.P., 1999. Neuronal-specific and nerve growth factor-inducible expression directed by the preprotachykinin-A promoter delivered by an adeno-associated virus vector. Neuroscience 94, 997-1003]. In this communication, we demonstrate that an E box element at -60, in part, regulates the activity of this rtPPT-A promoter fragment in DRG neurones in response to NGF. Differential regulation of the promoter is observed in the presence or absence of NGF when the E Box site is present. Under basal conditions binding of proteins to this -60 element may antagonise promoter activity. Hence, in the absence of NGF, mutation of the -60 E box increased reporter gene expression. Further, comparison of levels of reporter gene expression supported by both WT and mutated promoter indicate that in the presence of NGF the -60 E box element also plays a role as an activator domain. This represents a novel mechanism for NGF regulation of rtPPT-A. Similarly, an important role for this signalling pathway was observed in neonate rat DRG neuronal cultures, which require NGF for their survival, namely mutation of the -60 element resulted in higher levels of reporter gene expression.

MeSH terms

  • Animals
  • Animals, Newborn
  • Base Sequence
  • Cells, Cultured
  • Ganglia, Spinal / cytology*
  • Gene Expression Regulation*
  • Genes, Reporter
  • Genetic Vectors
  • Molecular Sequence Data
  • Nerve Growth Factor / metabolism*
  • Neurons / cytology
  • Neurons / metabolism*
  • Promoter Regions, Genetic*
  • Protein Precursors / genetics*
  • Protein Precursors / metabolism
  • Rats
  • Rats, Wistar
  • Regulatory Elements, Transcriptional*
  • Tachykinins / genetics*
  • Tachykinins / metabolism
  • Upstream Stimulatory Factors / genetics
  • Upstream Stimulatory Factors / metabolism

Substances

  • Protein Precursors
  • Tachykinins
  • Upstream Stimulatory Factors
  • Usf1 protein, rat
  • preprotachykinin
  • Nerve Growth Factor