A novel cis-acting element regulates HES-1 gene expression in P19 embryonal carcinoma cells treated with retinoic acid.
The regulatory mechanisms of mammalian hairy and Enhancer of split homologue-1 (HES-1) genes were examined in mouse P19 embryonic carcinoma cells (P19 cells). Undifferentiated P19 stem cells expressed a basal level of the HES-1 gene, whereas the expression of this gene was increased upon induction of the cells to a neural cell lineage using retinoic acid (RA). Reporter co-transfection analysis identified an activating region within the upstream promoter region of HES-1 from nucleotides -201 to -172. This activating region, called activating region X (ARX), shows a high GC content and contains both an AP-2 binding motif and a CCAAT box. An electrophoretic mobility shift assay using nuclear proteins extracted from P19 cells showed that ARX forms a specific DNA-protein complex. Importantly, ARX-dependent transcription, as well as ARX-binding activity, was significantly increased in P19 cells treated with RA. These results indicate that ARX transduces signals that up-regulate HES-1 gene expression in response to RA-treatment. Thus, a novel cis-acting element involved in HES-1 gene regulation that plays a role in RA-induced neural differentiation of P19 cells has been identified.
Wakabayashi
N
N
Department of Molecular Embryology, Research Institute for Microbial Diseases, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan.
Kageyama
R
R
Habu
T
T
Doi
T
T
Morita
T
T
Nozaki
M
M
Yamamoto
M
M
Nishimune
Y
Y
D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics*; D009687:Nuclear Proteins / Q000378:metabolism; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger / Q000235:genetics; D000072056:Transcription Factor HES-1; D014157:Transcription Factors / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D000072056:Transcription Factor HES-1; D014157:Transcription Factors; D014212:Tretinoin; C489734:Hes1 protein, mouse