Tissue-specific and glucose-responsive expression of the pancreatic derived factor (PANDER) promoter

Biochim Biophys Acta. 2005 Sep 25;1730(3):215-25. doi: 10.1016/j.bbaexp.2005.07.003.

Abstract

Pancreatic derived factor (PANDER) is a recently identified cytokine-like protein that is dominantly expressed in the islets of Langerhans of the pancreas. To investigate the mechanism of tissue-specific regulation of PANDER, we identified and characterized the promoter region. The transcriptional start site was identified 520 bp upstream of the translational start codon by 5'-RLM-RACE. Computer algorithms identified several islet-associated and glucose-responsive binding motifs that included A and E boxes, hepatocyte nuclear factors 1 and 4, Oct-1, and signal transducer and activator of transcription 3, and 5. Reporter gene analysis revealed cell type-specific PANDER promoter expression in islet and liver-derived cell lines. Levels of PANDER mRNA were directly concordant to the observed cell type-specific PANDER promoter gene expression. The minimal element was mapped to the 5'-UTR and located between +200 and +491 relative to the transcriptional start site and imparted maximal gene expression. In addition, several putative glucose-responsive binding sites were further functionally characterized to reveal critical regulatory elements of PANDER. The PANDER promoter was demonstrated to be glucose-responsive in a dose-dependent manner in murine insulinoma beta-TC3 cells and primary murine islets, but unresponsive in glucagon-secreting alpha-TC3 cells. Our findings revealed that the 5'-UTR of PANDER contains the minimal element for gene expression and imparts both tissue-specificity and glucose-responsiveness. The regulation of PANDER gene expression mimics that of insulin and suggests a potential biological function of PANDER involved in metabolic homeostasis.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 5' Untranslated Regions
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Line, Tumor
  • Consensus Sequence
  • Cytokines / genetics
  • Cytokines / metabolism*
  • Genes, Reporter
  • Glucose / metabolism*
  • Green Fluorescent Proteins / metabolism
  • Insulinoma
  • Islets of Langerhans / chemistry
  • Islets of Langerhans / cytology
  • Islets of Langerhans / metabolism*
  • Luciferases / analysis
  • Luciferases / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • NIH 3T3 Cells
  • Pancreas / chemistry*
  • Pancreas / cytology
  • Pancreatic Neoplasms
  • Promoter Regions, Genetic*
  • RNA, Messenger / metabolism
  • Rats
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transcription, Genetic

Substances

  • 5' Untranslated Regions
  • Cytokines
  • PANDER protein, mouse
  • RNA, Messenger
  • Green Fluorescent Proteins
  • Luciferases
  • Glucose

Associated data

  • GENBANK/AJ888873