Submitted to: Biology of Reproduction Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 3/30/2001
Publication Date: 12/20/2001
Citation: Xu, N., Matsuda, F., Christenson, R.K., Imakawa, K., Sakai, S. 2001. Expression of interferon-tau is regulated by protooncogene c-jun and co-activator CBP [abstract]. Biology of Reproduction. 64 (Supplement 1):187. (Abstract # 206) Interpretive Summary:
Technical Abstract: Regulation of interferon-tau (IFNtau) gene expression has been studied, however, the molecular mechanisms by which IFNtau gene is regulated have not been elucidated. In the present study, we investigated effects of co-activators, cAMP-response element binding protein (CREB)-binding protein (CBP) and p300, on ovine IFNtau (oIFNtau) gene activation in the transient transfection system using human choriocarcinoma JEG3 cells. The oIFNtau gene promoter/enhancer (-654 to +1 bases)-luciferase reporter construct (oIFNtau-pGL-3) was co-transfected with an expression construct of CBP (CBP/RSV) and/or p300 (pCMV-p300-HA). Levels of oIFNtau gene transactivation increased 1.9 +/ 0.2 and 3.0 +/ 0.4 fold when co-transfected with CBP and p300, respectively. These expressions further increased with a protein kinase C activator (PKC), phorbol 12-myristate 13-acetate (PMA) treatment, 4.7 +/ 0.7 and 3.7 +/ 0.5 fold, respectively. However, co-transfection of both CBP and p300 with or without PMA did not transactivate the oIFNtau construct beyond the level induced by the CBP plus PMA treatment. In addition, effects of protooncogenes, c-jun and c-fos, were examined by this transient transfection system. Transactivation of oIFNtau with c-jun was 3.5 +/ 0.6 and 2.9 +/ 0.3 fold with or without PMA, respectively, whereas c-fos did not affect its expression. Co-transfection of both c-jun and CBP resulted in 2.9 +/ 0.4 fold increase, which was further enhanced by PMA treatment (9.3 +/ 0.3 fold). These observations suggest that oIFNtau transactivation is regulated by c-jun and the effect is mediated through CBP.