Human FBP1 gene promoter and induction of hFBP1 expression in HepG2 by C/EBPα or HNF4α.

<p>(A) Nucleotide sequence of human FBP1 promoter with various putative transcription factor binding sites identified by PROMO [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0194252#pone.0194252.ref034" target="_blank">34</a>] and JASPAR databases [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0194252#pone.0194252.ref035" target="_blank">35</a>]. The binding sites of previously identified transcription factors including Sp1, USFs, NF-κB [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0194252#pone.0194252.ref031" target="_blank">31</a>] and VDRE [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0194252#pone.0194252.ref036" target="_blank">36</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0194252#pone.0194252.ref037" target="_blank">37</a>] are also included. (B) Western blot analysis of HepG2 cells transfected with pcDNA3 (empty vector), pcDNA3-C/EBPα or pcDNA3-HNF4α using anti-C/EBPα or anti-HNF4α antibodies. Control loading was assessed by probing the blot with anti-β-actin antibody. (C) qRT-PCR of FBP1 expression of HepG2 cells transfected with empty vector, C/EBPα or HNF4α. Human FBP1 mRNA expression was normalized with that of 18s rRNA, and shown as relative expression. (D) qRT-PCR of FBP1 expression in Huh7 cells transfected with empty vector, C/EBPα or HNF4α. The values obtained from cells transfected with pcDNA3-C/EBPα or pcDNA3-HNF4α were relative to that obtained from cells transfected with empty vector, which was arbitrarily set as 1. The values shown are means ± standard deviation of three independent experiments (n = 3). The statistical analysis was conducted by ANNOVA test where *p < 0.01 and **p < 0.05.