Work

Mechanism by which the IFN-β enhanceosome activates transcription

Year: 1999

Type: article

Abstract: We demonstrate that in contrast to previous findings by using simple synthetic promoters or activators, the natural IFN-beta enhanceosome activates transcription by causing a dramatic increase of the rate by which preinitiation complexes assemble at the promoter. This effect totally depends on the recruitment of the CBP-PolII holoenzyme by the enhanceosome, because its depletion from the extract decelerates the rate of transcription. However, addition of the CBP-PolII holoenzyme back to these extracts fully restores the speed by which the enhanceosome activates transcription. Strikingly, preincubation of the enhanceosome with the CBP-RNA PolII holoenzyme complex results in instant assembly of preinitiation complexes. In contrast, individual IFN-beta gene activators function solely by increasing the number of functional preinitiation complexes and not the rate of their assembly. Thus, fast recruitment of the CBP-RNA PolII holoenzyme complex is critical for the rapid activation of IFN-beta gene expression by virus infection.

Source: Proceedings of the National Academy of Sciences

DOI: 10.1073/pnas.96.23.13108

Authors: Junming Yie, Kate Senger, Dimitris Thanos

Institutions: Columbia University, Harvard University

Language: English

Topic: Genomics and Chromatin Dynamics

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: March of Dimes Foundation, National Institutes of Health, National Eye Institute, National Institute of General Medical Sciences

Awards: G1254785288, G1291675960, TRAINING FOR CAREERS IN MOLECULAR OPHTHALMOLOGY, High Mobility Group Protein HMG I(Y) in Transcription