A regulatory shortcut between the Snf1 protein kinase and RNA polymerase II holoenzyme

AUTOR(ES)

Kuchin, Sergei

FONTE

The National Academy of Sciences

RESUMO

RNA polymerase II holoenzymes respond to activators and repressors that are regulated by signaling pathways. Here we present evidence for a “shortcut” mechanism in which the Snf1 protein kinase of the glucose signaling pathway directly regulates transcription by the yeast holoenzyme. In response to glucose limitation, the Snf1 kinase stimulates transcription by holoenzyme that has been artificially recruited to a reporter by a LexA fusion to a holoenzyme component. We show that Snf1 interacts physically with the Srb/mediator proteins of the holoenzyme in both two-hybrid and coimmunoprecipitation assays. We also show that a catalytically hyperactive Snf1, when bound to a promoter as a LexA fusion protein, activates transcription in a glucose-regulated manner; moreover, this activation depends on the integrity of the Srb/mediator complex. These results suggest that direct regulatory interactions between signal transduction pathways and RNA polymerase II holoenzyme provide a mechanism for transcriptional control in response to important signals.

Documentos Relacionados

• Regulatory Interactions between the Reg1-Glc7 Protein Phosphatase and the Snf1 Protein Kinase
• Glucose-regulated interaction of a regulatory subunit of protein phosphatase 1 with the Snf1 protein kinase in Saccharomyces cerevisiae
• Identification of protein kinase SNF1 in CitEST
• N-Terminal Mutations Modulate Yeast Snf1 Protein Kinase Function
• Mutational analysis of the Saccharomyces cerevisiae SNF1 protein kinase and evidence for functional interaction with the SNF4 protein.