Activation of the Na+/H+ exchanger promoter by the transcription factor AP-2

• Author(s) / Creator(s)

  • Dyck, Jason
  • Silva, Norma Lucena C. L.
  • Fliegel, Larry

• We have isolated and characterized regions important for expression of the mouse NaGraphic/HGraphic exchanger gene. A 1.1-kilobase fragment upstream of the 5′-untranslated region contains specific DNA motifs characteristic of promoter and enhancer elements including a TATA box, two CAAT boxes, an SP-1 site, a cyclic AMP response element-binding site, and an AP-2-like site. This 1.1-kilobase fragment directs transcription of a luciferase reporter gene in mouse fibroblasts (NIH 3T3) and human Hep G2 cells. Deletion or mutation of an AP-2-like site 100 base pairs from the start site of transcription resulted in loss of most of the reporter plasmid activity. In addition, cotransfection of an AP-2 expression plasmid and the mouse promoter/luciferase plasmid increased the amount of NaGraphic/HGraphic exchanger-directed transcription in AP-2-deficient Hep G2 cells. Moreover, mobility shift analysis indicated that a putative AP-2-binding site is capable of binding purified AP-2 protein and a specific protein from nuclear extracts of NIH 3T3 cells. The results show that the transcription factor AP-2 may play an important role in regulation of transcription of the mouse NaGraphic/HGraphic exchanger gene.

• Date created

  1995-01-01

• Subjects / Keywords

  • Camp Action
  • Acid
  • Promoter Sequences
  • Binding-Proteins
  • Cells
  • Acetyl-Coa Carboxylase
  • Protein-Kinase-C
  • Na/H Antiporter
  • Expression
  • Insulin Induction

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/r3-3xf7-ww87

• License

  © 1995 Jason Dyck et al. This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.