The first intron of human hsp90β gene is not only essential in maintaining high constitutive expression but also critical for heat shock inducibility of the hsp90β gene. Typical HSEs in ...The first intron of human hsp90β gene is not only essential in maintaining high constitutive expression but also critical for heat shock inducibility of the hsp90β gene. Typical HSEs in the first intron play a vital role in the heat induced expression of human hsp90β gene. Slot blot analysis shows that hsp90β gene mRNA transcripts initiated from the 3’ of the first intron dominates over that of the first exon. The intronic HSEs of the hsp90β gene show much higher binding affinity toward the recombinant heat shock factor HSF1 than that of the recombinant heat shock factor HSF2.展开更多
Human heat shock protein 90β gene (hsp90β) is a constitutively expressed heat shock gene existing in most of cell types tested that can be further induced by heat shock. Chloramphenical acetyl transferase (CAT) repo...Human heat shock protein 90β gene (hsp90β) is a constitutively expressed heat shock gene existing in most of cell types tested that can be further induced by heat shock. Chloramphenical acetyl transferase (CAT) reporter plasmids driven by different regulatory fragments of hsp90B gene were constructed and transfected into Jurkat cells to explore the role of a cAMP response element (CRE) in the upstream of the gene. Results show that, in comparison with the wild type construct, a severe reduction (~2/3) in the increased folds of promoter activity induced by heat shock at 42℃ for 1 h was observed in a construct with CRE-containing fragment (-173/-91bp) deleted. Electrophoretic mobility shift assays (EMSA) showed that phosphorylated CRE-bindingprotein (CREB) in the nuclear extract of heat shocked Jur-kat cells is specifically bound to the fragment. Additionally, both of the phosphorylation on CREB and the activity of protein kinase A (PKA) were found in Jurkat cells to be enhanced with extending time of展开更多
文摘The first intron of human hsp90β gene is not only essential in maintaining high constitutive expression but also critical for heat shock inducibility of the hsp90β gene. Typical HSEs in the first intron play a vital role in the heat induced expression of human hsp90β gene. Slot blot analysis shows that hsp90β gene mRNA transcripts initiated from the 3’ of the first intron dominates over that of the first exon. The intronic HSEs of the hsp90β gene show much higher binding affinity toward the recombinant heat shock factor HSF1 than that of the recombinant heat shock factor HSF2.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 39930050 and 39770169).
文摘Human heat shock protein 90β gene (hsp90β) is a constitutively expressed heat shock gene existing in most of cell types tested that can be further induced by heat shock. Chloramphenical acetyl transferase (CAT) reporter plasmids driven by different regulatory fragments of hsp90B gene were constructed and transfected into Jurkat cells to explore the role of a cAMP response element (CRE) in the upstream of the gene. Results show that, in comparison with the wild type construct, a severe reduction (~2/3) in the increased folds of promoter activity induced by heat shock at 42℃ for 1 h was observed in a construct with CRE-containing fragment (-173/-91bp) deleted. Electrophoretic mobility shift assays (EMSA) showed that phosphorylated CRE-bindingprotein (CREB) in the nuclear extract of heat shocked Jur-kat cells is specifically bound to the fragment. Additionally, both of the phosphorylation on CREB and the activity of protein kinase A (PKA) were found in Jurkat cells to be enhanced with extending time of
