Serum responsiveness and UV inducibility of rat PCNA promoter are modulated via the proximal ATF/CRE and AP-1 sites

• Main Authors: Lai, Y.C., 賴怡琪
• Other Authors: Liu Yin-Chang
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/01942875438060542699

碩士 === 國立清華大學 === 生命科學系 === 86 === Proliferating cell nuclear antigen (PCNA), an auxiliary factor of DNA polymerase delta, is required in eukaryotic DNA replication and repair. Previous studies by series deletion have shown that the rat PCNA promoter possesses the serum responsiveness and UV inducibility in the region of nucleotide between -70 and +125 which contains one AP-1 site and one ATF/ CRE site. Furthermore, it was found that the AP-1 mutation partially loses the serum responsiveness and UV inducibility. In this thesis,we try to characterize the role of AP-1 site and proximal ATF/CRE site in rat PCNA promoter in the aspects of serum responsiveness and UV inducibility. Using megapriming PCR method, we constructed the site-specific ATF/CRE mutated promoter and the AP-1/ATF double mutated promoter. In comparison with the AP-1 mutant promoter, the ATF/CRE mutant promoter partially loses the serum responsiveness but represents more UV inducibility even than the wild type. Furthermore, when the AP-1/ATF double mutated promoter was transfected stably into CHO.K1 cells, the serum responsiveness and UV inducibility decreased remarkably. Results of this thesis suggest that the proximal AP-1 site and ATF/CRE site are both necessary for basal activity and play crucial roles in serum stimulation of rat PCNA promoter. On the other hand, the ATF/CRE site may be a negative regulator in UV induction of rat PCNA promoter. It remains for further investigation.