The nexin link and B-tubule glutamylation maintain the alignment of outer doublets in the ciliary axoneme

Lea M. Alford, Daniel Stoddard, Jennifer H. Li, Emily L. Hunter, Douglas Tritschler, Raqual Bower, Daniela Nicastro, Mary E. Porter, Winfield S. Sale

Research output: Contribution to journalArticle

10 Scopus citations

Abstract

We developed quantitative assays to test the hypothesis that the N-DRC is required for integrity of the ciliary axoneme. We examined reactivated motility of demembranated drc cells, commonly termed “reactivated cell models.” ATP-induced reactivation of wild-type cells resulted in the forward swimming of ∼90% of cell models. ATP-induced reactivation failed in a subset of drc cell models, despite forward motility in live drc cells. Dark-field light microscopic observations of drc cell models revealed various degrees of axonemal splaying. In contrast, >98% of axonemes from wild-type reactivated cell models remained intact. The sup-pf4 and drc3 mutants, unlike other drc mutants, retain most of the N-DRC linker that interconnects outer doublet microtubules. Reactivated sup-pf4 and drc3 cell models displayed nearly wild-type levels of forward motility. Thus, the N-DRC linker is required for axonemal integrity. We also examined reactivated motility and axoneme integrity in mutants defective in tubulin polyglutamylation. ATP-induced reactivation resulted in forward swimming of >75% of tpg cell models. Analysis of double mutants defective in tubulin polyglutamylation and different regions of the N-DRC indicate B-tubule polyglutamylation and the distal lobe of the linker region are both important for axonemal integrity and normal N-DRC function.

Original languageEnglish (US)
Pages (from-to)331-340
Number of pages10
JournalCytoskeleton
Volume73
Issue number7
DOIs
StatePublished - Jun 1 2016

    Fingerprint

Keywords

  • axoneme
  • cilia
  • doublet microtubule
  • DRC
  • dynein
  • dynein regulatory complex
  • N-DRC
  • nexin

ASJC Scopus subject areas

  • Structural Biology
  • Cell Biology

Cite this

Alford, L. M., Stoddard, D., Li, J. H., Hunter, E. L., Tritschler, D., Bower, R., Nicastro, D., Porter, M. E., & Sale, W. S. (2016). The nexin link and B-tubule glutamylation maintain the alignment of outer doublets in the ciliary axoneme. Cytoskeleton, 73(7), 331-340. https://doi.org/10.1002/cm.21301