Regulation of microtubule dynamics by a protein interaction network at microtubule ends consisting of EB1, CLIP-170, XKCM1 and XMAP215 - an in vitro reconstitution

• Applicant: Dr. Thomas Surrey
• Subject Area: Biophysics
• Term: from 2009 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 156864440

The regulation of microtubule dynamics is crucial for the internal organization of eukaryotic cells. Several microtubule-associated proteins modulate the dynamics of microtubules and are known to be crucial for fundamental processes in cell and developmental biology, such as proper cell division or the establishment of cell polarity. There is increasing evidence that these regulators form a protein interaction network at dynamic microtubule ends. Until today it is not understood how this network regulating microtubule function acts as a system. Recently, end binding protein 1 (EB1) has been identified as the hub of this network using an in vitro reconstitution approach. This opens now the possibility to study how EB1 controls the other regulators of microtubule dynamics in this network. We will reconstitute here the core of this regulatory network in vitro. We will focus on the elucidation of the molecular mechanism of cell cycle dependent control of the activity of this network. A combination of biochemical methods and quantitative time-resolved fluorescence microscopy down to the single molecule level will be used to analyze in a minimal and well-controlled system the rules underlying physiological regulation of microtubule dynamics. This work will lead to a molecular understanding of the functioning of a dynamic protein interaction network at a systems level.

• DFG Programme: Research Grants
• International Connection: United Kingdom