Self-organized DNA/F-actin gels: entangled networks of nematic domains with tunable density

ORAL

Abstract

We examine mixtures of DNA and F-actin as a model system of like-charged rigid rods and flexible chains. Confocal microscopy reveals the formation of elongated nematic F-actin domains reticulated via defect-free vertices into a network, all embedded in a mesh of random DNA. Synchrotron x-ray scattering results indicate that the DNA mesh squeezes the F-actin domains into a nematic state via the osmotic pressure of uncondensed counterions, so that the inter-actin spacing within the domains decreases with increasing DNA concentration. These observations are consistent with arguments based on electrostatics and nematic elasticity.

*This work was supported in part by the NSF DMR-0409769, NIH 1R21DK6843-01, the Cystic Fibrosis Foundation, and the Institute for Complex Adaptive Matter.

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Authors

  • John Butler

    • University of Illinois at Urbana-Champaign

  • Olena Zribi

    • Harvard University
    • University of Illinois at Urbana-Champaign

  • Ivan Smalyukh

    • University of Colorado at Boulder

  • Olena Zribi

    • Harvard University
    • University of Illinois at Urbana-Champaign

  • Ramin Golestanian

    • University of Sheffield

  • Olena Zribi

    • Harvard University
    • University of Illinois at Urbana-Champaign

  • Gerard C. L. Wong

    • University of Illinois at Urbana-Champaign
    • UIUC
    • Dept. of Materials Science and Engr., Univ. of Illinois at Urbana-Champaign
    • Department of Materials Science Engineering, Department of Physics, and Seitz Materials Research Lab, University of Illinois, Urbana-Champaign