The microtubule minus-end-binding protein patronin/PTRN-1 is required for axon regeneration in C. elegans

Cell Rep. 2014 Nov 6;9(3):874-83. doi: 10.1016/j.celrep.2014.09.054. Epub 2014 Oct 23.


Precise regulation of microtubule (MT) dynamics is increasingly recognized as a critical determinant of axon regeneration. In contrast to developing neurons, mature axons exhibit noncentrosomal microtubule nucleation. The factors regulating noncentrosomal MT architecture in axon regeneration remain poorly understood. We report that PTRN-1, the C. elegans member of the Patronin/Nezha/calmodulin- and spectrin-associated protein (CAMSAP) family of microtubule minus-end-binding proteins, is critical for efficient axon regeneration in vivo. ptrn-1-null mutants display generally normal developmental axon outgrowth but significantly impaired regenerative regrowth after laser axotomy. Unexpectedly, mature axons in ptrn-1 mutants display elevated numbers of dynamic axonal MTs before and after injury, suggesting that PTRN-1 inhibits MT dynamics. The CKK domain of PTRN-1 is necessary and sufficient for its functions in axon regeneration and MT dynamics and appears to stabilize MTs independent of minus-end localization. Whereas in developing neurons, PTRN-1 inhibits activity of the DLK-1 mitogen-activated protein kinase (MAPK) cascade, we find that, in regeneration, PTRN-1 and DLK-1 function together to promote axonal regrowth.

Publication types

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

MeSH terms

  • Animals
  • Axons / metabolism*
  • Caenorhabditis elegans / cytology
  • Caenorhabditis elegans / metabolism*
  • Caenorhabditis elegans Proteins / chemistry
  • Caenorhabditis elegans Proteins / metabolism*
  • Microtubule-Associated Proteins / chemistry
  • Microtubule-Associated Proteins / metabolism*
  • Microtubules / metabolism*
  • Motor Neurons / cytology
  • Motor Neurons / metabolism
  • Mutation
  • Polymerization
  • Protein Binding
  • Protein Structure, Tertiary
  • Regeneration*
  • Sensory Receptor Cells / cytology
  • Sensory Receptor Cells / metabolism
  • Structure-Activity Relationship
  • Up-Regulation


  • Caenorhabditis elegans Proteins
  • Microtubule-Associated Proteins
  • PTRN-1 protein, C elegans