Department of Biotechnology and Brain Korea 21 Center for Silver-Bio Industrialization, Dong-A University, Busan 604-714, Korea.
BMB Rep. 2011 Jun;44(6):405-9. doi: 10.5483/BMBRep.2011.44.6.405.
The present study demonstrated that valproic acid (VPA) transcriptionally regulates human GM3 synthase (hST3Gal V), which catalyzes ganglioside GM3 biosynthesis in ARPE-19 human retinal pigment epithelial cells. For this, we characterized the promoter region of the hST3Gal V gene. Functional analysis of the 5'-flanking region of the hST3Gal V gene revealed that the -177 to -83 region functions as the VPA-inducible promoter and that the CREB/ATF binding site at -143 is crucial for VPA-induced expression of hST3Gal V in ARPE-19 cells. In addition, the transcriptional activity of hST3Gal V induced by VPA in ARPE-19 cells was inhibited by SP600125, a c-Jun N-terminal kinase (JNK) inhibitor. In summary, our results identified the core promoter region in the hST3Gal V promoter and for the first time demonstrated that ATF2 binding to the CREB/ATF binding site at -143 is essential for transcriptional activation of hST3Gal V in VPA-induced ARPE-19 cells.
本研究表明，丙戊酸（VPA）可转录调控人 GM3 合成酶（hST3Gal V），后者在 ARPE-19 人视网膜色素上皮细胞中催化神经节苷脂 GM3 的生物合成。为此，我们对 hST3Gal V 基因的启动子区进行了特征描述。hST3Gal V 基因 5'侧翼区的功能分析表明，-177 至-83 区作为 VPA 诱导启动子发挥作用，而-143 处的 CREB/ATF 结合位点对于 VPA 诱导 ARPE-19 细胞中 hST3Gal V 的表达至关重要。此外，VPA 在 ARPE-19 细胞中诱导的 hST3Gal V 转录活性被 c-Jun N-末端激酶（JNK）抑制剂 SP600125 抑制。总之，我们的研究结果确定了 hST3Gal V 启动子中的核心启动子区，并首次证明了 ATF2 与-143 处的 CREB/ATF 结合位点的结合对于 VPA 诱导的 ARPE-19 细胞中 hST3Gal V 的转录激活至关重要。
