First Author | Ezashi T | Year | 1998 |
Journal | Proc Natl Acad Sci U S A | Volume | 95 |
Issue | 14 | Pages | 7882-7 |
PubMed ID | 9653109 | Mgi Jnum | J:48739 |
Mgi Id | MGI:1274936 | Doi | 10.1073/pnas.95.14.7882 |
Citation | Ezashi T, et al. (1998) Control of interferon-tau gene expression by Ets-2. Proc Natl Acad Sci U S A 95(14):7882-7 |
abstractText | Expression of the multiple interferon-tau (IFN-tau) genes is restricted to embryonic trophectoderm of ruminant ungulate species for a few days in early pregnancy. The promoter regions of these genes are highly conserved. A proximal (bp -91 to -69) sequence has been implicated in controlling trophoblast-specific expression. Here it was used as a target for yeast one-hybrid screening of a day 13 conceptus cDNA library. Two transcription factors of the Ets family, Ets-2 and GABPalpha, were identified, consistent with the observation that active ovine IFN-tau genes contain a single 10-bp Ets motif (core: GGAA) in the proximal segment, whereas three known inactive ovine genes contain a mutated core motif (TGAA). Cotransfection of a promoter- (-126 to +50) luciferase reporter construct from an active gene (bovineIFN-tau1; boIFNT1) and an Ets-2 expression plasmid in human JAr cells provided up to a 30-fold increase in reporter expression, whereas promoters from inactive genes were not transactivated. GABPalpha alone was ineffective and had only a approximately 2-fold positive effect when coexpressed with its partner GABPbeta. Other Ets-related transcription factors, which were not detected in the genetic screen, also provided a range of lesser transactivation effects. Coexpression of Ets-2 and activated Ras failed to transactivate the IFNT promoter greater than Ets-2 alone in JAr cells. The presence of Ets-2 in nuclei of embryonic trophectoderm was confirmed immunocytochemically. Together, these data suggest that Ets-2 plays a role in the transient expression of the nonvirally inducible IFNT genes. |