Objective    To identify the usage of ESR1 promoters in two kinds of liver cells.     Methods    We cultured and stimulated HepG2 and L02 cells by routine methods. After the cells were cross-linked by formaldehyde and chromatin was sonicated by ultrasonic

we performed RNA polymerase Ⅱ-chromatin immunoprecipitations (PolⅡ-ChIP) to precipitate the promoter sequences and validated them by PCR.      Results    After PolⅡ-ChIP assay for the liver cells stimulated by β-estradiol

E1

E2 and F promoters of ESR1 could be precipitated in HepG2 cells

while only D promoter could be precipitated in L02 cells.     Conclusion    We found that the transcription and expression of ESR1 in different liver cells are regulated by different promoters

like what we found ESR1 expression in HepG2 cells by E1

E2 and F promoters

ESR1 expression in L02 cell by D promoter.