Retinoic acid receptors and GATA transcription factors activate the transcription of the human lecithin:retinol acyltransferase gene.

TitleRetinoic acid receptors and GATA transcription factors activate the transcription of the human lecithin:retinol acyltransferase gene.
Publication TypeJournal Article
Year of Publication2009
AuthorsCai K, Gudas LJ
JournalInt J Biochem Cell Biol
Volume41
Issue3
Pagination546-53
Date Published2009 Mar
ISSN1878-5875
KeywordsAcyltransferases, Cell Line, Tumor, Epithelial Cells, GATA4 Transcription Factor, Humans, Male, Membrane Proteins, Promoter Regions, Genetic, Prostate, Prostatic Neoplasms, Protein Binding, Receptors, Retinoic Acid, Response Elements, Transcriptional Activation, Transfection, Vitamin A
Abstract

Lecithin:retinol acyltransferase (LRAT) catalyzes the esterification of retinol (vitamin A). Retinyl esters and LRAT protein levels are reduced in many types of cancer cells. We present data that both the LRAT and retinoic acid receptor beta(2) (RARbeta(2)) mRNA levels in the human prostate cancer cell line PC-3 are lower than those in cultured normal human prostate epithelial cells (PrEC). The activity of the human LRAT promoter (2.0 kb) driving a luciferase reporter gene in PC-3 cells is less than 40% of that in PrEC cells. Retinoic acid (RA) treatment increased this LRAT promoter-luciferase activity in PrEC cells, but not in PC-3 cells. Deletion of various regions of the human LRAT promoter demonstrated that a 172-bp proximal promoter region is essential for LRAT transcription and confers RA responsiveness in PrEC cells. This 172-bp region, contained within the 186 bp pLRAT/luciferase construct, has five putative GATA binding sites. Cotransfection of RARbeta(2) or RARgamma and the transcription factor GATA-4 increased LRAT (pLRAT186) promoter activity in both PrEC and PC-3 cells. In addition, we found that both retinoic acid and retinol induced transcripts for the STRA6 gene, which encodes a membrane receptor involved in retinol (vitamin A) uptake, in PrEC cells but not in PC-3 cells. In summary, our data show that the transcriptional regulation of the human LRAT gene is aberrant in human prostate cancer cells and that GATA transcription factors are involved in the transcriptional activation of LRAT in PrEC cells.

DOI10.1016/j.biocel.2008.06.007
Alternate JournalInt. J. Biochem. Cell Biol.
PubMed ID18652909
PubMed Central IDPMC2628449
Grant ListR01 CA097543 / CA / NCI NIH HHS / United States
R01 CA097543-02 / CA / NCI NIH HHS / United States
R01 CA097543-03 / CA / NCI NIH HHS / United States