Kinesins are eukaryotic cytoskeletal proteins best known for their motile activity, but they are also important regulators of microtubule (MT) dynamics, the ability of the MT polymer to grow or shrink. This project seeks to establish the molecular mechanism of microtubule (MT) dynamics regulation by members of the kinesin superfamily. Regulation of MT dynamics by these kinesins play important roles in a variety of cell processes such as mitosis, cytokinesis, neural development and control of cilia and centriole length, but the mechanisms by which these kinesins stabilize or destabilize MTs are not fully clear. We will test the general hypothesis that all these kinesin affect MT-dynamics by modifying the structure of tubulin to favor or disfavor the formation of the inter-tubulin contacts that hold the MT polymer together. To address this hypothesis we will use electron microscopy and other approaches to determine the structure of tubulin complexes of three model kinesins. The proposal has two general aims. The fist aim is to establish the mechanism of MT depolymerization by the kinesins KLP10A and Kar3.
The second aim addresses the mechanism of MT stabilization by the kinesin KIF14.
The proposed work will investigate the molecular structure and mechanism of action of a group of kinesin proteins that modulate the ability of the microtubular cytoskeleton to elongate and shrink. Due to the role that these kinesins have in cell division and tumor growth they are also attractive targets for the development of anti-cancer drugs. Thus, the proposed studies may help the rational design of a new generation of drugs to treat cancer.
| Benoit, Matthieu P M H; Sosa, Hernando (2018) Use of Single Molecule Fluorescence Polarization Microscopy to Study Protein Conformation and Dynamics of Kinesin-Microtubule Complexes. Methods Mol Biol 1665:199-216 |
| Benoit, Matthieu P M H; Asenjo, Ana B; Sosa, Hernando (2018) Cryo-EM reveals the structural basis of microtubule depolymerization by kinesin-13s. Nat Commun 9:1662 |
| Chatterjee, Chandrima; Benoit, Matthieu P M H; DePaoli, Vania et al. (2016) Distinct Interaction Modes of the Kinesin-13 Motor Domain with the Microtubule. Biophys J 110:1593-1604 |
| Sosa, Hernando; Asenjo, Ana B; Peterman, Erwin J G (2010) Structure and dynamics of the kinesin-microtubule interaction revealed by fluorescence polarization microscopy. Methods Cell Biol 95:505-19 |
