Plastin increases cortical connectivity to facilitate robust polarization and timely cytokinesis

J Cell Biol. 2017 May 1;216(5):1371-1386. doi: 10.1083/jcb.201603070. Epub 2017 Apr 11.


The cell cortex is essential to maintain animal cell shape, and contractile forces generated within it by nonmuscle myosin II (NMY-2) drive cellular morphogenetic processes such as cytokinesis. The role of actin cross-linking proteins in cortical dynamics is still incompletely understood. Here, we show that the evolutionarily conserved actin bundling/cross-linking protein plastin is instrumental for the generation of potent cortical actomyosin contractility in the Caenorhabditis elegans zygote. PLST-1 was enriched in contractile structures and was required for effective coalescence of NMY-2 filaments into large contractile foci and for long-range coordinated contractility in the cortex. In the absence of PLST-1, polarization was compromised, cytokinesis was delayed or failed, and 50% of embryos died during development. Moreover, mathematical modeling showed that an optimal amount of bundling agents enhanced the ability of a network to contract. We propose that by increasing the connectivity of the F-actin meshwork, plastin enables the cortex to generate stronger and more coordinated forces to accomplish cellular morphogenesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Actins / metabolism*
  • Actomyosin / metabolism
  • Animals
  • Caenorhabditis elegans / cytology*
  • Caenorhabditis elegans / embryology
  • Cell Polarity*
  • Cell Shape
  • Cytokinesis*
  • Membrane Glycoproteins / metabolism*
  • Microfilament Proteins / metabolism*
  • Morphogenesis
  • Time Factors
  • Zygote / cytology


  • Actins
  • Membrane Glycoproteins
  • Microfilament Proteins
  • plastin
  • Actomyosin