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鉴于热休克蛋白９０β（ｈｓｐ９０β）基因内含子中含有维生素Ｄ３受体（ＶＤＲ）结合位点，为探讨作为核受体家族成员的ＶＤＲ是否对核受体特异分子伴侣的ｈｓｐ９０β基因的表达具有调控作用，我们开展了本项研究。分别将野生型ＶＤＲ、含Ｎ端（１～１３３氨基酸残基）及Ｃ端（２８１～４２７氨基酸残基）片段的ＶＤＲ突变体真核表达质粒与人ｈｓｐ９０β基因调控片段（－１０３９／＋１５３１）介导的氯霉素乙酰基转移酶（ＣＡＴ）报告基因质粒共转染Ｊｕｒｋａｔ细胞，检测正常及经热休克（４２℃，１ｈ）处理后细胞裂解液中ＣＡＴ活性。结果表明ＶＤＲＮ端增强、而Ｃ端抑制ｈｓｐ９０β的组成性表达；在热诱导条件下野生型ＶＤＲ对ｈｓｐ９０β的表达有一定的抑制作用，而其Ｃ端片段的抑制较强。为进一步研究ＶＤＲ对细胞内源性热休克基因表达的影响，我们用ＲＴＰＣＲ方法研究了ＶＤＲ的对细胞内ｈｓｐ９０β基因ｍＲＮＡ水平的影响，发现ＶＤＲ过表达对ｈｓｐ９０β的热诱导表达明显抑制。结果提示ＶＤＲ对ｈｓｐ９０β基因的组成性和热诱导表达的调控机制不同。
In view of the presence of vitamin D receptor (VDR) binding sites in the intron of the heat shock protein 90β (hsp90β) gene, in order to investigate whether VDR, a member of the nuclear receptor family, regulates the expression of the hsp90β gene of a nuclear receptor-specific chaperone Role, we conducted this study. The wild-type VDR, the eukaryotic expression plasmid of VDR mutant containing N-terminal (1-133 amino acid residues) and C-terminal (281-427 amino acid residues) fragments were respectively compared with the human hsp90β gene regulatory fragment (-1039 / + 1531) Mediated chloramphenicol acetyltransferase (CAT) reporter plasmid was cotransfected into Jurkat cells, and the activity of CAT in cell lysates was detected under normal and heat shock (42 ℃, 1h). The results showed that VDRN end enhanced, and C end inhibited the constitutive expression of hsp90β; wild-type VDR under heat-induced expression of hsp90β a certain degree of inhibition, while its C-terminal fragment was strongly inhibited. To further study the effect of VDR on the expression of endogenous heat shock genes in cells, we used RT-PCR to study the effect of VDR on the mRNA expression of hsp90βin cells. We found that the overexpression of VDR significantly inhibited the heat-inducible expression of hsp90β. The results suggest that the regulatory mechanism of VDR on constitutive and heat-induced expression of hsp90βgene is different.