Differential hypersensitivity to DNase I in the regulatory region of human hsp90 beta gene in heat shock and constitutive expression.

DNase I hypersensitivity analysis is a useful tool to investigate impact of structure changes in chromatin on the expression of a gene. In order to unravel chromatin regulation on human hsp90 beta gene, differential sensitivity to DNase I in non-treated and heat-shocked Jurkat cells are examined. Four major hypersensitive sites at -120/-20 bp (HS1), +360 bp (HS2), +630/+780 bp (HS4) and around +1020 bp (HS5) with respect to the transcription start site of hsp90 beta gene have been identified. The HS1 is shared by both constitutive and heat shock, while the intronic sites of HS4 and HS5 are elicited by heat shock and HS2 is illustrated only in constitutive expression. In addition, distal HSs at around 8.7 kb upstream and 6.8 kb downstream are found in both constitutive and heat shock expression, which indicate that the boundaries of the hsp90 beta gene extend for some 16 kb. The HS patterns confirm chromatin regulation in the expression of hsp90 beta gene under various treatments.