Sterol-regulatory-element-binding protein 2 and nuclear factor Y control human farnesyl diphosphate synthase expression and affect cell proliferation in hepatoblastoma cells

Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
Biochemical Journal (Impact Factor: 4.4). 05/2010; 429(2):347-57. DOI: 10.1042/BJ20091511
Source: PubMed


FDPS (farnesyl diphosphate synthase) catalyses the formation of farnesyl diphosphate, a key intermediate in the synthesis of cholesterol and isoprenylated cellular metabolites. FDPS is also the molecular target of nitrogen-containing bisphosphonates, which are used as bone-antiresorptive drugs in various disorders. In the present study, we characterized the sterol-response element and NF-Y (nuclear factor Y)-binding site in the human FDPS promoter. Using a luciferase assay, electrophoretic mobility-shift assay and chromatin immunoprecipitation assay, we demonstrated that these elements are responsible for the transcription of the FDPS gene, and that its transcriptional activation is mediated by SREBP-2 (sterol-regulatory-element-binding protein 2) and NF-Y. We also investigated whether sterol-mediated FDPS expression is involved in the cell proliferation induced by zoledronic acid, an FDPS inhibitor. We show that the SREBP-2- and NF-Y-mediated regulation of FDPS gene transcription modulates cell proliferation. These results suggest that SREBP-2 and NF-Y are required to trigger cell proliferation through the induction of FDPS expression and that the pharmacological action of zoledronic acid is involved in this pathway.

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Available from: Toshiya Tanaka
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    • "Conversely, NF-YB repressed genes were statistically retrieved in cell cycle, microtubule/cytoskeleton and DNA-metabolism functions, as already observed upon NF-YB siRNA transfection (25). NF-YB inactivation led to the up-regulation of relatively few GO terms, among which were those of lipid and sterol metabolism: this is somewhat surprising, since NF-Y is known to cooperate with SREBP1 and SREBP2 to activate many of these genes (39,40). "
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