Project description:HNF4a is an important liver transcription factor that regulates at least a thousand genes in the liver. Here we used expression profiling in HepG2 cells, a hepatocellular carcinoma cell line, in which HNF4a was knocked down by RNAi to identify some of those target genes. This dataset accompanies the article in Hepatology 2010 Feb;51(2):642-53. Integrated approach for the identification of human hepatocyte nuclear factor 4alpha target genes using protein binding microarrays by Bolotin E, Liao H, Ta TC, Yang C, Hwang-Verslues W, Evans JR, Jiang T, Sladek FM. RNA interference (RNAi) against HNF4a2 was performed in HepG2 cells using small, interfering RNAs (siRNAs) corresponding to nucleotides +179 to +197 of human HNF4A (NM_178849, sense siRNA: 5'-UGUGCAGGUGUUGACGAUGdTdT-3', antisense siRNA 5'-CAUCGUCAACACCUGCACAdTdT-3') (Dharmacon, Lafayette, CO). Total RNA was extracted with Trizol (Life Technologies, Carlsbad, CA) and reverse transcribed with the Reverse Transcription System (Promega, Madison, WI). Polymerase chain reaction (PCR) amplification was performed in the linear range (see Supporting Table 3B for a list of PCR primers). Expression profiling analysis was performed with Affymetrix oligonucleotide arrays (HGU133 Plus 2.0) using RNA from control (PGL3 siRNA) or treated (HNF4a siRNA) HepG2 cells
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Specific regulation of target genes by transforming growth factor-β (TGF-β) in a given cellular context is determined in part by transcription factors and cofactors that interact with the Smad complex. In the present study, we determined Smad2 and Smad3 (Smad2/3) binding regions in the promoters of known genes in HepG2 hepatoblastoma cells, and compared them to those in HaCaT epidermal keratinocytes to elucidate the mechanisms of cell type- and context-dependent regulation of transcription induced by TGF-β. Our results show that 81% of the Smad2/3 binding regions in HepG2 cells were not shared with those found in HaCaT cells. Hepatocyte nuclear factor 4α (HNF4α) is expressed in HepG2 cells, but not in HaCaT cells, and the HNF4α binding motif was identified as an enriched motif in the HepG2-specific Smad2/3 binding regions. ChIP-sequencing analysis of HNF4A binding regions under TGF-β stimulation revealed that 32.5% of the Smad2/3 binding regions overlapped HNF4A bindings. MIXL1 was identified as a new combinatorial target of HNF4A and Smad2/3, and both the HNF4A protein and its binding motif were required for the induction of MIXL1 by TGF-β in HepG2 cells. These findings generalize the importance of binding of HNF4A on Smad2/3 binding genomic regions for HepG2-specific regulation of transcription by TGF-β, and suggest that certain transcription factors expressed in a cell-type-specific manner play important roles in the transcription regulated by the TGF-β-Smad signaling pathway. HepG2 cells were treated with TGF-beta for 1.5 h or left untreated. anti-HNF4A ChIP-seq was performed. One lane was used for each sample.