Regulation of cell polarity by interactors of the PAK-family kinase Ste20 in budding yeast

• Applicant: Dr. Thomas Höfken
• Subject Area: Cell Biology
• Term: from 2005 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 12469333

The small GTPase Cdc42 plays a key role in cell polarity. In the budding yeast Saccharomyces cerevisiae it is required at different stages of the cell cycle during vegetative growth but also during mating and filamentous growth. The PAK-family kinase Ste20 is one of the downstream effectors of Cdc42. Since only few substrates for Ste20 have been described, we recently carried out a screen in order to identify novel interactors of Ste20. The aim of this project is the characterization of these interactions. Using yeast genetics as well as biochemical approaches such as co-immunoprecipitations and affinity purifications we will examine whether the interactions are physiologically relevant. Further, it will be tested whether the proteins are phosphorylated in a Ste20-dependent manner. Depending on the protein, functional assays (e.g. actin nucleation) will be carried out to gain a better understanding of the underlying molecular mechanisms.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1111: Cell Polarity