Cyclic AMP response element binding protein(CREB) participates in the heat-inducible expression of human hsp90β gene  

作　　者：Bingsheng Liu Ninghua Wu Yufei Shen 

出　　处：《Chinese Science Bulletin》2001年第19期1645-1649,共5页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant Nos. 39930050 and 39770169).

摘　　要：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 ofHuman 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 ofhsp90β 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 °C for 1 h was observed in a construct with CRE-containing fragment (?173/?91bp) deleted. Electrophoretic mobility shift assays (EMSA) showed that phosphorylated CRE-binding protein (CREB) in the nuclear extract of heat shocked Jurkat 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 heat shock treatment. Our results indicate that in addition to the intronic HSE/HSF pathway, phosphorylated CREB also participates in the heat shock induced expression of humanhsp90β gene via its interaction with CRE which may be regulated by PKA-signaling pathway.

关 键 词：hsp90β GENE CRE CREB PKA HEAT shock. 

分 类 号：R363[医药卫生—病理学]