Complexes between STE5 and components of the pheromone-responsive mitogen-activated protein kinase module.

AUTOR(ES)

Marcus, S

RESUMO

We present genetic evidence for complex formation of STE5 and the STE11, STE7, and FUS3 protein kinases, the pheromone-responsive mitogen-activated protein kinase module of Saccharomyces cerevisiae. Interaction between STE5 and STE11 is not dependent on STE7, and interaction between STE5 and STE7 does not require STE11. The N-terminal regulatory domain of STE11 is both necessary and sufficient for interaction with STE5. Interaction between STE7 and STE11 is bridged by STE5, suggesting the formation of a multiprotein complex. We also demonstrate biochemical interaction between STE5 and STE11 by using a combination of bacterially expressed fusion proteins and extracts prepared from yeast. Our results suggest that STE5 is a scaffolding protein that facilitates interactions between components of the pheromone-responsive mitogen-activated protein kinase module. We further propose that such scaffolding proteins serve to inhibit cross-talk between functionally unrelated mitogen-activated protein kinase modules within the same cell.

Documentos Relacionados

• Constitutive Activation of the Fission Yeast Pheromone-Responsive Pathway Induces Ectopic Meiosis and Reveals Ste11 as a Mitogen-Activated Protein Kinase Target
• Effect of the Pheromone-Responsive Gα and Phosphatase Proteins of Saccharomyces cerevisiae on the Subcellular Localization of the Fus3 Mitogen-Activated Protein Kinase
• Mutational Analysis Suggests That Activation of the Yeast Pheromone Response Mitogen-activated Protein Kinase Pathway Involves Conformational Changes in the Ste5 Scaffold Protein
• Functional domains of the yeast STE12 protein, a pheromone-responsive transcriptional activator.
• Mitogen-Activated Protein Kinases with Distinct Requirements for Ste5 Scaffolding Influence Signaling Specificity in Saccharomyces cerevisiae†