CCAAT/enhancer binding protein has a negative role in human hepatic stimulator substant expression in HepG2 cells

doi:10.3969/j.issn.1006-7795.2014.05.023

Abstract

Abstract:

Objective To study the site of a negative role of CCAAT/enhancer binding protein α (C/EBPα) in human hepatic stimulator substant(hHSS) expression and the affect of the regulation mechanism of EGF. Methods EMSAs were carried on to examine whether candidate transcription factor binds to the hHSS promoter. mRNA levels of hHSS expression were measured by real-time PCR. Protein levels of hHSS expression were measured by Western blot.Results Down-regulation of C/EBP expression significantly enhanced hHSS mRNA expression, yet did not affect EGF inhibition of hHSS mRNA expression. The results from EMSAs clearly demonstrate that C/EBP binds the C/EBP1 site. Conclusion C/EBP does not participate in EGF inhibition of hHSS mRNA, whereas it has a negative role in hHSS expression by binding the C/EBP1 site.

Key words: hepatic stimulator substance, epidermal growth factor, CCAAT/enhancer binding protein α

CLC Number:

Q503

Wu Yuan, Dong Lingyue, An Wei. CCAAT/enhancer binding protein has a negative role in human hepatic stimulator substant expression in HepG2 cells[J]. Journal of Capital Medical University, 2014, 35(5): 634-639.

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URL: https://journal03.magtech.org.cn/Jweb_sdykdxxb/EN/10.3969/j.issn.1006-7795.2014.05.023

https://journal03.magtech.org.cn/Jweb_sdykdxxb/EN/Y2014/V35/I5/634

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