Reconstitution of the interface between microtubules and cortical actin

• Antragsteller: Dimitris Liakopoulos, Ph.D.
• Fachliche Zuordnung: Biochemie
• Förderung: Förderung von 2010 bis 2013
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 184471447

Asymmetric cell divisions are common for stem cells or cells that differentiate during development. For an asymmetric division to occur, the mitotic spindle must be positioned parallel to the axis of cell polarity. Spindle positioning depends in part on microtubuleassociated complexes that link astral microtubules to the cortical actin cytoskeleton and generate forces that bring the mitotic spindle to its correct position. In budding yeast, the protein Kar9, the functional homolog of the APC tumor suppressor, a number of the microtubule-associated proteins and type V myosin, form a protein complex that links astral microtubules to cortical actin. Our laboratory has shown that phosphorylation, sumoylation and ubiquitylation regulate assembly and disassembly of this complex. However, its biochemical properties, its stoichiometry and its molecular structure remain largely unknown. Subject of this proposal is the purification of Kar9 and its interacting partners, the reconstitution of Kar9 interactions in vitro and the detailed biochemical and structural analysis of the complexes formed. The ultimate goal is to reconstitute the microtubule-actin interface and its regulation. The experiments proposed aim to uncover the molecular basis of force generation as astral microtubules interact with actin filaments.

• DFG-Verfahren: Sachbeihilfen