Trim28 and HDAC1 cooperate to repress E2F3- and E2F4-driven transcription.
A, control and Trim28 knockdown H1299 cells were transfected in triplicate with the indicated promoter-reporter, pRL-TK reporter, and protein expression plasmids. Cells were harvested 48 h after transfection for determination of luciferase levels. B, H1299 cells were transfected in triplicate with the indicated promoter-reporter, pRL-TK reporter, and protein expression plasmids. Cells were harvested 48 h after transfection for determination of luciferase levels. C and D, control and Trim28 knockdown cells were infected with the indicated adenoviruses. The expression of individual proteins was verified by Western blotting with E2F-specific antibodies (minor cross-reactivity is evident in C). The expression of target genes was determined by real-time PCR (D). Asterisks represent significant p values, as follows: *: p < 0.05, **: p < 0.01, and ***: p < 0.005.