The roles of MSK1 and its potential targets in EBV reactivation

• Main Authors: Tsung-Yu Chao, 趙崇宇
• Other Authors: Chi-Ju Chen
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/74dvgx

碩士 === 國立陽明大學 === 微生物及免疫學研究所 === 106 === Epstein-Barr virus (EBV) belongs to human herpesviruses which can establish latent infection in B cells and reactivated by stimuli. The immediately early gene BZLF1 is responsible for EBV reactivation in B cells. In our preliminary study, the phosphorylated H3S10 on Zp was increased during sodium butyrate plus 12-O-Tetradecanoylphorbol-13-acetate (TPA) caused reactivation. We therefore found MSK1 is essential for EBV reactivation in Raji cells, which is MSK1 kinase activity dependent. We investigate the effect of MSK1 downstream targets which were reported to be important in reactivation of Kaposi’s sarcoma-associated herpesvirus, cAMP response element binding protein (CREB) and lysine demethylase 3A (KDM3A), to EBV reactivation. We also examined the effect of MSK1 to EBV reactivation in NA cells, a nasopharyngeal carcinoma cell line, and we found that the MSK1 expression level and MSK1 kinase activity are both important for EBV reactivation in NA cells. For the case of Raji cells, we carried out ChIP against CREB to survey CREB binding on Zp during reactivation. The result showed that CREB binding on Zp was not increased at the time point near the strongest CREB phosphorylation time point. As the CREB expression can rescue the MSK1 knockdown effect in EBV reactivation, which indicated MSK1 might regulate EBV reactivation through CREB, whether CREB plays a role in MSK1 mediated EBV reactivation needs to be further examined. We constructed the constitutively active CREB-Y134F and dominant negative CREB-S133A expressing lentivirus plasmids. Through studying the effect of different forms of CREB to MSK1 mediated EBV reactivation, we hope to verify the relation between MSK1 and CREB. To KDM3A, we use pan-KDM-family inhibitor IOX-1 to examine the involvement of KDM family members and we knocked down the KDM3A to further investigate the role of KDM3A in EBV reactivation as well. As the IOX-1 inhibit EBV reactivation while knockdown of KDM3A cannot, we speculate that MSK1 regulates EBV reactivation through another member of KDM family rather than KDM3A.