[Effects of sodium butyrate on acetylation of histone in gamma-globin gene promoter regions in K562 cells: a study using chromatin immunoprecipitation].

Objective To develop a real-time PCR-based chromatin immunoprecipitation(ChIP) assay for determining the effect of sodium butyrate on acetylation of histone in γ-globin gene promoter regions in K562 cells.Methods K562 cells were grown in the presence or absence of 0.5 mmol/L sodium butyrate for 48 h,and 1×107cells per group were used for real-time PCR-based ChIP with anti-acetylated histone H3 or H4 antibodies.The levels of acetylated histone H3 and H4(acH3 and acH4) in Gγ-and Aγ-globin gene promoter regions were measured.Results In the K562 cells with sodium butyrate treatment or without any treatment,the levels of acH3 or acH4 in Gγ-or Aγ-globin gene promoter were higher than that in the necdin gene(negative control).Compared with the untreated K562 cells,the cells treated with 0.5 mmol/L sodium butyrate showed a 3.1-fold or 2.6-fold increase in acH3 or acH4 in Gγ-globin gene promoter region,with also a 3.7-fold or 3.2-fold increase in acH3 or acH4 in Aγ-globin gene promoter region,respectively(P0.01).Conclusion We have successfully developed a real-time PCR-based ChIP assay for analyzing the acetylation of histone H3 and H4 in γ-globin gene promoter regions.Our results support the role of sodium butyrate in increasing the level of acetylated histone in γ-globin gene promoter regions.