NF-IL6, A MEMBER OF THE C/EBP FAMILY, REGULATES E1A-RESPONSIVE PROMOTERS IN THE ABSENCE OF E1A

作者：SPERGEL JM; HSU W; AKIRA S; THIMMAPPAYA B; KISHIMOTO T; CHENKIANG S

来源：Journal of Virology, 1992, 66(2): 1021-1030.

A cDNA encoding NF-IL6, an interleukin-6 (IL-6)-regulated human nuclear factor of the C/EBP family, is demonstrated to complement the transactivation function of E1A. The endogenous NF-IL6 level varies according to cell type and correlates positively with an IL-6-regulated cellular E1A-substituting activity that was described recently (J. M. Spergel and S. Chen-Kiang, Proc. Natl. Acad. Sci. USA 88: 6472-6476, 1991). When expressed by transfection in cells which contain low levels of NF-IL6 and are incapable of complementing the function of E1A proteins, NF-IL6 also transactivates the E1A-responsive E2ae and E1B promoters, to the same magnitude as E1A. Activation by NF-IL6 is concentration dependent and sequence specific: mutational studies of the E2ae promoter suggest that the promoter-proximal NF-IL6 recognition site functions as a dominant negative regulatory site whereas the promoter-distal NF-IL6 recognition site is positively regulated at low NF-IL6 concentrations and negatively regulated when the NF-IL6 level is high. Consistent with these functions, NF-IL6 alone is sufficient to complement an E1A deletion mutant dl312 in viral infection, when expressed at appropriate concentrations. These results identify NF-IL6 as a sequence-specific cellular nuclear factor which regulates E1A-responsive genes in the absence of E1A.

• 出版日期1992-2
• 单位西北大学