These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Regulation of cellular retinol-binding protein type II gene expression by arachidonic acid analogue and 9-cis retinoic acid in caco-2 cells.
    Author: Suruga K, Mochizuki K, Suzuki R, Goda T, Takase S.
    Journal: Eur J Biochem; 1999 May; 262(1):70-8. PubMed ID: 10231366.
    Abstract:
    We previously showed that unsaturated fatty acids induced gene expression of cellular retinol-binding protein type II (CRBPII) in rat jejunum [Suruga, K., Suzuki, R., Goda, T. and Takase, S. (1995) J. Nutr. 125, 2039-2044]. In the present study, we investigated this induction mechanism(s) using the human intestinal Caco-2 cell line. The postconfluent mature Caco-2 cells were maintained in serum-free medium containing arachidonic acid or its analogue, 5,8,11, 14-eicosatetraynoic acid (ETYA). Northern blot analysis showed that these compounds induced CRBPII mRNA levels to rise and that this induction was more effective when combined with 9-cis retinoic acid. This effect was independent of cycloheximide and inhibited by actinomycin D. Nuclear run-on assays confirmed that the ETYA and 9-cis retinoic acid-induced increase of CRBPII mRNA levels was due to an increased rate of transcription of its gene. In Caco-2 cells, the transcripts of peroxisome proliferator-activated receptor alpha (PPARalpha) and retinoid X receptor alpha (RXRalpha), which were activated by their ligands ETYA and 9-cis retinoic acid, respectively, were coexpressed. The gel shift study using rat CRBPII gene nuclear receptor response elements (RXRE, RE2, RE3) revealed that several forms of nuclear proteins from Caco-2 cells specifically bound to these elements. Some of these protein/DNA complexes reacted to both anti-RXRalpha and anti-PPAR antibodies. In addition, in-vitro synthesized RXRalpha and PPARalpha cooperatively bound to these elements as a heterodimer and these binding activities were enhanced by addition of ETYA or arachidonic acid but not by addition of 9-cis retinoic acid. These studies suggest that fatty acid or its analogue may regulate CRBPII gene expression through PPAR/RXR heterodimer bound to the nuclear receptor response element(s) of the CRBPII genes.
    [Abstract] [Full Text] [Related] [New Search]