Nuclear choline acetyltransferase activates transcription of a high-affinity choline transporter

J Biol Chem. 2011 Feb 18;286(7):5836-45. doi: 10.1074/jbc.M110.147611. Epub 2010 Dec 16.

Abstract

Choline acetyltransferase (ChAT) synthesizes the neurotransmitter, acetylcholine, at cholinergic nerve terminals. ChAT contains nuclear localization signals and is also localized in the nuclei of neural and non-neuronal cells. Nuclear ChAT might have an as yet unidentified function, such as transcriptional regulation. In this study, we investigated the alteration of candidate gene transcription by ChAT. We chose high affinity choline transporter (CHT1) and vesicular acetylcholine transporter (VACHT) as candidate genes, which function together with ChAT in acetylcholine production. Using SH-SY5Y human neuroblastoma cells stably expressing wild-type human ChAT, we found that overexpressed ChAT enhanced transcription of the CHT1 gene but not the VACHT gene. In contrast, nuclear localization signal disrupted, and catalytically inactive mutant ChATs could not induce, CHT1 expression. Additionally, ChAT did not alter CHT1 expression in non-neuronal HEK293 cells. Our results suggest that ChAT activates the transcription of selected target genes in neuronal cells. Both enzymatic activity and nuclear translocation of ChAT are required for its transcriptional enhancement.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholine / biosynthesis
  • Acetylcholine / genetics
  • Active Transport, Cell Nucleus / physiology
  • Cell Line
  • Cell Line, Tumor
  • Cell Nucleus / genetics
  • Cell Nucleus / metabolism*
  • Choline O-Acetyltransferase / genetics
  • Choline O-Acetyltransferase / metabolism*
  • Gene Expression Regulation / physiology*
  • HEK293 Cells
  • Humans
  • Mutation
  • Neurons / metabolism*
  • Organ Specificity / physiology
  • Symporters / biosynthesis*
  • Symporters / genetics
  • Transcription, Genetic / physiology*
  • Vesicular Acetylcholine Transport Proteins / biosynthesis*
  • Vesicular Acetylcholine Transport Proteins / genetics

Substances

  • SLC18A3 protein, human
  • SLC5A7 protein, human
  • Symporters
  • Vesicular Acetylcholine Transport Proteins
  • Choline O-Acetyltransferase
  • Acetylcholine