Maintenance of open chromatin and selective genomic occupancy at the cell cycle-regulated histone H4 promoter during differentiation of HL-60 promyelocytic leukemia cells

Hayk Hovhannisyan, Brian Cho, Partha Mitra, Martin Montecino, Gary S. Stein, Andre J. Van Wijnen, Janet L. Stein

Resultado de la investigación: Contribución a una revistaArtículo

23 Citas (Scopus)

Resumen

During the shutdown of proliferation and onset of differentiation of HL-60 promyelocytic leukemia cells, expression of the cell cycle-dependent histone genes is downregulated at the level of transcription. To address the mechanism by which this regulation occurs, we examined the chromatin structure of the histone H4/n (FO108, H4FN) gene locus. Micrococcal nuclease, DNase I, and restriction enzymes show similar cleavage sites and levels of sensitivity at the H4/n locus in both proliferating and differentiated HL-60 cells. In contrast, differentiation-related activation of the cyclin-dependent kinase inhibitor p21cip1/WAF1 gene is accompanied by increased nuclease hypersensitivity. Chromatin immunoprecipitation assays of the H4/n gene reveal that acetylated histones H3 and H4 are maintained at the same levels in proliferating and postproliferative cells. Thus, the chromatin of the H4/n locus remains in an open state even after transcription ceases. Using ligation-mediated PCR to visualize genomic DNase I footprints at single-nucleotide resolution, we find that protein occupancy at the site II cell cycle element is selectively diminished in differentiated cells while the site I element remains occupied. Decreased occupancy of site II is reflected by loss of the site II binding protein HiNF-P. We conclude that H4 gene transcription during differentiation is downregulated by modulating protein interaction at the site II cell cycle element and that retention of an open chromatin conformation may be associated with site I occupancy.

Idioma originalInglés
Páginas (desde-hasta)1460-1469
Número de páginas10
PublicaciónMolecular and Cellular Biology
Volumen23
N.º4
DOI
EstadoPublicada - feb 2003

Áreas temáticas de ASJC Scopus

  • Biología molecular
  • Genética
  • Biología celular

Huella Profundice en los temas de investigación de 'Maintenance of open chromatin and selective genomic occupancy at the cell cycle-regulated histone H4 promoter during differentiation of HL-60 promyelocytic leukemia cells'. En conjunto forman una huella única.

  • Citar esto