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