The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 

Hrs1/Med3 is a Cyc8-Tup1 corepressor target in the RNA polymerase II holoenzyme.

The Srb/Mediator, a multisubunit subcomplex of the RNA polymerase II (RNA pol II) holoenzyme has been proposed to function as a control panel regulating transcription in response to gene-specific activator proteins. In this report, we identify the Mediator subunit Hrs1/Med3 as a physical target for Cyc8-Tup1, a yeast transcriptional corepressor. Two-hybrid and glutathione S-transferase interaction assays show that Hrs1 can associate directly with Cyc8-Tup1. Moreover, affinity chromatography experiments, using yeast protein extracts, reveal that Cyc8-Tup1 co-purifies with Hrs1 and with additional Mediator subunits in a Hrs1-dependent manner. These observations suggest that Cyc8-Tup1 contacts the Mediator complex via its interaction with the Hrs1 subunit. Further on, genetic analysis indicates that increased Hrs1 dosage can alleviate Cyc8-Tup1-mediated repression, suggesting that Hrs1/Mediator's function is inhibited upon its interaction with Cyc8-Tup1. Finally, artificial holoenzyme recruitment assays support a model by which the contact between the corepressor and the Hrs1/Mediator may prevent pol II holoenzyme recruitment to the core promoter. These data, together with previous genetic evidence, establish a functional and physical interaction between the Cyc8-Tup1 corepressor and the RNA pol II holoenzyme and support a central role of the Mediator complex in transcriptional repression.[1]

References

  1. Hrs1/Med3 is a Cyc8-Tup1 corepressor target in the RNA polymerase II holoenzyme. Papamichos-Chronakis, M., Conlan, R.S., Gounalaki, N., Copf, T., Tzamarias, D. J. Biol. Chem. (2000) [Pubmed]
 
WikiGenes - Universities