A degron-based strategy reveals new insights into Aurora B function in C. elegans

PLoS Genet. 2021 May 20;17(5):e1009567. doi: 10.1371/journal.pgen.1009567. eCollection 2021 May.

Abstract

The widely conserved kinase Aurora B regulates important events during cell division. Surprisingly, recent work has uncovered a few functions of Aurora-family kinases that do not require kinase activity. Thus, understanding this important class of cell cycle regulators will require strategies to distinguish kinase-dependent from independent functions. Here, we address this need in C. elegans by combining germline-specific, auxin-induced Aurora B (AIR-2) degradation with the transgenic expression of kinase-inactive AIR-2. Through this approach, we find that kinase activity is essential for AIR-2's major meiotic functions and also for mitotic chromosome segregation. Moreover, our analysis revealed insight into the assembly of the ring complex (RC), a structure that is essential for chromosome congression in C. elegans oocytes. AIR-2 localizes to chromosomes and recruits other components to form the RC. However, we found that while kinase-dead AIR-2 could load onto chromosomes, other components were not recruited. This failure in RC assembly appeared to be due to a loss of RC SUMOylation, suggesting that there is crosstalk between SUMOylation and phosphorylation in building the RC and implicating AIR-2 in regulating the SUMO pathway in oocytes. Similar conditional depletion approaches may reveal new insights into other cell cycle regulators.

Publication types

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

MeSH terms

  • Animals
  • Aurora Kinase B / metabolism*
  • Caenorhabditis elegans / cytology*
  • Caenorhabditis elegans / enzymology*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Chromosome Segregation*
  • Chromosomes / metabolism
  • Meiosis / genetics
  • Mitosis / genetics
  • Oocytes / cytology
  • Oocytes / enzymology*
  • Phosphorylation
  • Reproducibility of Results
  • Spindle Apparatus / enzymology
  • Sumoylation

Substances

  • Caenorhabditis elegans Proteins
  • Aurora Kinase B
  • air-2 protein, C elegans