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The structure and dynamics of microtubule bundles mediated by motor proteins

ORAL

Abstract

Mixtures of polar microtubule (MT) filaments and force-generating motor proteins self-organize by cross-linking and sliding MTs into dense networks of polar and apolar bundles. We can measure the geometric structure of these MT-based bundles using small-angle x-ray scattering and determine the polar structure of these materials by taking advantage of their chiral crystal lattice which produces constructive interference of second harmonic signal between polar-aligned MTs. A transition in the bundles' structure to a compressed square lattice corresponds to a change in the microtubules extensile sliding dynamics. These results are useful in understanding the dynamics of filamentous active materials. The quantified geometric packing of microtubule bundles can be incorporated into a framework of highly cross-linked active gel theories.

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Presenters

  • Bezia Lemma

    Physics, Harvard

Authors

  • Bezia Lemma

    Physics, Harvard

  • Linnea Lemma

    Physics, Brandeis, University of California Santa Barbara, Physics Department, Brandeis University

  • Sebastian Fuerthauer

    Flatiron Institute

  • Michael John Shelley

    Flatiron Institute, New York University, Courant Institute, New York University, CIMS, New York University

  • Zvonimir Dogic

    Physics, UC Santa Barbara, University of California Santa Barbara, University of California, Santa Barbara, Physics, University of California Santa Barbara, Physics Department, University of Caifornia Santa Barbara, Physics, University of California, Santa Barbara

  • Daniel Needleman

    Harvard, Harvard University