Regulation of LPCAT3 by LXR.

Abstract : In this work we analyzed the transcriptome profiles of chicken hepatoma cells (LMH) in response to T0901317, a pharmacological agonist of the liver X receptor (LXR). Through an in silico search for LXRE (LXR response element) consensus sequences in the promoter of genes whose expression was shown to be sensitive to TO901317, we identified a LXRE in the promoter of the LPCAT3 (lysophosphatidylcholine acyltransferase 3). This motif is highly conserved between species. We further investigated the regulation of this gene and showed that the expression of LPCAT3 was induced both in chicken and human hepatoma cells (LMH and HuH-7, respectively) in response to T0901317. Transactivation and electrophoretic mobility shift assays allowed us to locate a functional LXRE in the chicken LPCAT3 promoter. Altogether these data evidence for the first time that the chicken LPCAT3 gene is a direct target of LXR and therefore suggest a new role for LXR in phospholipid homeostasis.