Restriction of apolipoprotein A-IV gene expression to the intestine villus depends on a hormone-responsive element and parallels differential expression of the hepatic nuclear factor 4alpha and gamma isoforms

J Biol Chem. 2002 Sep 13;277(37):34540-8. doi: 10.1074/jbc.M206074200. Epub 2002 Jun 24.

Abstract

The apoA-I/C-III/A-IV gene cluster, like most intestine-specific genes, displays a specific pattern of expression along the intestinal cephalocaudal and crypt-to-villus axes. We have shown that this specific pattern of expression requires the distal apoA-IV promoter and the apoC-III enhancer. Using a new set of transgenic mice, we demonstrate here that the restriction of apoA-IV gene transcription to villus enterocytes requires a hormone-responsive element (HRE) located within the apoA-IV distal promoter. We showed, using nuclear extracts from villus or crypt epithelial cells, that this HRE bound the transcription factor hepatic nuclear factor 4 (HNF-4). We also found that the HNF-4gamma isoform was produced only in the villus, whereas the HNF-4alpha isoform was produced along the entire length of the crypt-to-villus axis. Our results demonstrate that the HRE of the distal apoA-IV promoter is responsible for the restriction of gene expression to villus epithelial cells and that this HRE binds HNF-4 isoforms. The in vivo observation of parallel gradients for apoA-IV and HNF-4gamma gene expression raises questions concerning whether this transcription factor plays a specific role in the control of enterocyte differentiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apolipoproteins A / genetics*
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • COS Cells
  • Cell Differentiation
  • DNA-Binding Proteins*
  • Enterocytes / metabolism*
  • Gene Expression Regulation
  • Hepatocyte Nuclear Factor 4
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred CBA
  • Mice, Transgenic
  • Phosphoproteins / genetics*
  • Promoter Regions, Genetic
  • Response Elements*
  • Transcription Factors / genetics*

Substances

  • Apolipoproteins A
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • DNA-Binding Proteins
  • Hepatocyte Nuclear Factor 4
  • Phosphoproteins
  • Tcfl4 protein, mouse
  • Transcription Factors
  • apolipoprotein A-IV