Microtubule severing by the katanin complex is activated by PPFR-1-dependent MEI-1 dephosphorylation

J Cell Biol. 2013 Aug 5;202(3):431-9. doi: 10.1083/jcb.201304174.

Abstract

Katanin is an evolutionarily conserved microtubule (MT)-severing complex implicated in multiple aspects of MT dynamics. In Caenorhabditis elegans, the katanin homologue MEI-1 is required for meiosis, but must be inactivated before mitosis. Here we show that PPFR-1, a regulatory subunit of a trimeric protein phosphatase 4 complex, enhanced katanin MT-severing activity during C. elegans meiosis. Loss of ppfr-1, similarly to the inactivation of MT severing, caused a specific defect in meiosis II spindle disassembly. We show that a fraction of PPFR-1 was degraded after meiosis, contributing to katanin inactivation. PPFR-1 interacted with MEL-26, the substrate recognition subunit of the CUL-3 RING E3 ligase (CRL3(MEL-26)), which also targeted MEI-1 for post-meiotic degradation. Reversible protein phosphorylation of MEI-1 may ensure temporal activation of the katanin complex during meiosis, whereas CRL3(MEL-26)-mediated degradation of both MEI-1 and its activator PPFR-1 ensure efficient katanin inactivation in the transition to mitosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism*
  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / metabolism*
  • Katanin
  • Microtubules / metabolism*
  • Multiprotein Complexes / metabolism
  • Phosphoprotein Phosphatases / metabolism*
  • Phosphorylation

Substances

  • Caenorhabditis elegans Proteins
  • Multiprotein Complexes
  • PPFR-1 protein, C elegans
  • Phosphoprotein Phosphatases
  • Adenosine Triphosphatases
  • MEI-1 protein, C elegans
  • Katanin