Evidence for a role of spindle matrix formation in cell cycle progression by antibody perturbation

PLoS One. 2018 Nov 28;13(11):e0208022. doi: 10.1371/journal.pone.0208022. eCollection 2018.

Abstract

In Drosophila it has recently been demonstrated that a spindle matrix in the form of a membrane-less macromolecular assembly embeds the microtubule-based spindle apparatus. In addition, two of its constituents, Megator and Chromator, were shown to function as spatial regulators of spindle checkpoint proteins. However, whether the spindle matrix plays a wider functional role in spatially regulating cell cycle progression factors was unknown. Here using a live imaging approach we provide evidence that a number of key cell cycle proteins such as Cyclin B, Polo, and Ran co-localize with the spindle matrix during mitosis. Furthermore, prevention of spindle matrix formation by injection of a function blocking antibody against the spindle matrix protein Chromator results in cell cycle arrest prior to nuclear envelope breakdown. In such embryos the spatial dynamics of Polo and Cyclin B enrichment at the nuclear rim and kinetochores is abrogated and Polo is not imported into the nucleus. This is in contrast to colchicine-arrested embryos where the wild-type dynamics of these proteins are maintained. Taken together these results suggest that spindle matrix formation may be a general requirement for the localization and proper dynamics of cell cycle factors promoting signaling events leading to cell cycle progression.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Antibodies / metabolism
  • Cell Cycle / drug effects
  • Cell Cycle / physiology*
  • Cell Cycle Proteins / metabolism*
  • Colchicine / pharmacology
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster
  • Embryonic Development / drug effects
  • Embryonic Development / physiology
  • Spindle Apparatus / metabolism*
  • Tubulin Modulators / pharmacology

Substances

  • Antibodies
  • Cell Cycle Proteins
  • Drosophila Proteins
  • Tubulin Modulators
  • Colchicine

Grants and funding

This work was supported by: KMJ and JJ, MCB0817107, National Science Foundation, www.nsf.gov<http://www.nsf.gov>; VA, Natural Sciences and Engineering Research Council of Canada, http://www.nserc-crsng.gc.ca; JG, United States Department of Agriculture National Institute of Food and Agriculture, https://www.nifa.usda.gov, Hatch project 1006350. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.