Proteins encoded by early region 1A (E1A) regulate transcription of viral and cellular genes. The mechanism of this trans-activation is not understood, but is of considerable interest as an example of transcription regulation through a cellular intermediate. We have therefore studied the effect of E1A products on the activity of the κ L chain gene promoter and enhancer. By using transient and stable transfections into lymphoid and nonlymphoid cells, we found that the E1A proteins have a pleiotropic effect on the regulation of the mouse κ-chain gene enhancer. In lymphoid cells the E1A products repress κ-chain enhancer, whereas in fibroblasts, the κ-chain enhancer is activated by the E1A products whether the E1A gene is in an extrachromosomal location or stably integrated in the genome. Furthermore, a functional κ-chain promoter, containing the octanucleotide and 'TATA' sequences is needed in order to be transcribed in E1A-producing cells. This ability of E1A products to negatively and positively regulate κ-chain transcription may reflect a more general phenomenon in which a given cellular protein could participate in a variety of different cellular controls.
|Original language||American English|
|Number of pages||8|
|Journal||Journal of Immunology|
|State||Published - 1988|