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Transcription control by E1A and MAP kinase pathway via Sur2 mediator subunit
Jennitte L Stevens1, Greg T Cantin, Gang Wang
1Molecular Biology Institute, University of California, Los Angeles, 611 Charles Young Drive East, Los Angeles, CA 90095, USA.
Science (New York, N.Y.)
|April 6, 2002
Summary
The Sur2 subunit is crucial for activating specific transcription factors, including adenovirus E1A and Elk-1, by recruiting the Mediator complex to promoters. This finding highlights distinct Mediator subunit roles in gene activation.
Area of Science:
- Molecular Biology
- Gene Regulation
- Cellular Signaling
Background:
- The Mediator complex is a transcriptional co-activator essential for gene expression.
- Specific subunits of Mediator interact with transcription factors to regulate gene activity.
- The Sur2 subunit's role in mammalian cells was previously uncharacterized.
Purpose of the Study:
- To investigate the function of the Sur2 subunit in mammalian Mediator complex.
- To determine the role of Sur2 in transcription factor activation and gene regulation.
Main Methods:
- Generation of Sur2 knockout (sur2-/-) mouse embryonic stem cells.
- Analysis of transcription factor activation, including adenovirus E1A and Elk-1.
- Investigating Mediator complex subunit interactions.
Main Results:
- Sur2 forms a stable subcomplex with TRAP/Med100 and 95 subunits.
- Knockout of Sur2 abrogates activation mediated by E1A-CR3 and Elk-1.
- Activation by other transcription factors remains unaffected, suggesting specificity.
Conclusions:
- Sur2 is a critical mammalian Mediator subunit involved in specific transcription factor pathways.
- Distinct activation domains of transcription factors may target different Mediator subunits.
- Mediator recruitment to promoters by E1A and Elk-1 is dependent on the Sur2 subunit.
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