Adenovirus E1a proteins repress transcription from the SV40 early promoter

Inhibition of p53-mediated transactivation and cell cycle arrest by E1A through its p300/CBP-interacting regionSelfcloseTable

“…To examine this possibility, we studied the e ect of E1A on transactivation of a yeast Gal4 DNA-binding site-CAT reporter gene by the yeast Gal4 DNA-binding domain fused to p53's transactivation domain (Gal4-p53 (aa 1 ± 42) ( Figure 3). We subcloned the DNAcassette encoding the fusion proteins downstream of a CMV immediate early promoter since it is known that the SV40 early promoter, present upstream of the Gal4-p53 fusions in the parent vectors, is inhibited by E1A (Velcich and Zi , 1985). Figure 3a shows that E1A inhibited transcriptional activity of the Gal4-p53 (aa 1 ± 42) fusion protein (compare lanes 5 vs 6, 7 and …”

Selective induction of human heat shock gene transcription by the adenovirus E1A gene products, including the 12S E1A product.

“…For instance, a role for ElA-mediated transcriptional repression in adenovirus transformation has been suggested (25,33). The ElA proteins can repress the activity of the simian virus 40, polyomavirus, or Ad2 ElA enhancers in transfection experiments (3,50) and the transcription of endogenous immunoglobulin genes (11). Several transformation-defective ElA mutants have been identified that are positive for induction of the E2, E3, and E4 mRNAs, as well as the human P-globin gene cloned into the adenovirus genome (25,33).…”

“…The adenovirus ElA gene is a regulatory gene that specifies products that both activate (2,16,35) and repress (3,11,50) transcription of unlinked genes. During a lytic viral infection, five early transcription units are stimulated by the action of the product of the 13S ElA RNA, a 289-amino-acid protein (42).…”

Identification of factors that interact with the E1A-inducible adenovirus E3 promoter.

“…The E1A gene can transactivate a number of viral and cellular genes, and in many cases the promoters of such genes have been analyzed genetically to locate sequences or elements essential for efficient transcription (for review, see Berk 1986). The E1A gene can also repress expression of certain viral and cellular genes, specifically those dependent on cis-acting enhancer elements for efficient transcription (Borrelli et al 1984;Hen et al 1985;Velcich and Ziff 1985). Transcription stimulation by the SV40, Py, and E1A (Borrelli et al 1984;Velcich and Ziff 1985) enhancers, as well as the cellular immunoglobulin heavy chain (Hen et al 1985) and insulin (Stein and Ziff 1987) enhancers, has been shown to be blocked by E1A protein.…”

“…At early times of infection, the E1A gene produces two transcripts, 12S and 13S in size, which encode products of 243 and 289 amino acids, respectively (Berk and Sharp 1978;Chow et al 1979;Perricaudet et al 1979;Kitchingman and Westphal 1980). Both products display regulatory activity; the product of 289 amino acids can trans-activate and repress gene transcription (Borrelli et al 1984;Velcich and Ziff 1985), whereas the protein of 243 amino acids, although it represses very efficiently (Borrelli et al 1984;Velcich and Ziff 1985), is generally found to be deficient in trans-activation (Carlock and Jones 1981;Montell et al 1982;Svensson and Akusjarvi 1984;Winberg and Shenk 1984;Lillie et al 1986;Moran et al 1986;Wu et al 1986a). Furthermore, extensive mutational analysis of the E1A gene has identified domains that are required for repression but not for trans-activation (Lillie et al 1986;Moran et al 1986;Schneider et al 1987).…”