Structural and Functional Recovery of Sensory Cilia in C. elegans IFT Mutants upon Aging

PLoS Genet. 2016 Dec 1;12(12):e1006325. doi: 10.1371/journal.pgen.1006325. eCollection 2016 Dec.

Abstract

The majority of cilia are formed and maintained by the highly conserved process of intraflagellar transport (IFT). Mutations in IFT genes lead to ciliary structural defects and systemic disorders termed ciliopathies. Here we show that the severely truncated sensory cilia of hypomorphic IFT mutants in C. elegans transiently elongate during a discrete period of adult aging leading to markedly improved sensory behaviors. Age-dependent restoration of cilia morphology occurs in structurally diverse cilia types and requires IFT. We demonstrate that while DAF-16/FOXO is dispensable, the age-dependent suppression of cilia phenotypes in IFT mutants requires cell-autonomous functions of the HSF1 heat shock factor and the Hsp90 chaperone. Our results describe an unexpected role of early aging and protein quality control mechanisms in suppressing ciliary phenotypes of IFT mutants, and suggest possible strategies for targeting subsets of ciliopathies.

MeSH terms

  • Aging / genetics
  • Animals
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / growth & development
  • Caenorhabditis elegans Proteins / biosynthesis
  • Caenorhabditis elegans Proteins / genetics*
  • Cilia / genetics*
  • Cilia / metabolism
  • Ciliopathies / genetics
  • Ciliopathies / therapy
  • Forkhead Transcription Factors / biosynthesis
  • Forkhead Transcription Factors / genetics*
  • HSP90 Heat-Shock Proteins / biosynthesis
  • HSP90 Heat-Shock Proteins / genetics*
  • Humans
  • Microtubules / genetics
  • Microtubules / metabolism
  • Molecular Chaperones / genetics
  • Mutation
  • Sensory Receptor Cells / metabolism
  • Transcription Factors / biosynthesis
  • Transcription Factors / genetics*

Substances

  • Caenorhabditis elegans Proteins
  • DAF-21 protein, C elegans
  • Forkhead Transcription Factors
  • HSP90 Heat-Shock Proteins
  • Molecular Chaperones
  • Transcription Factors
  • daf-16 protein, C elegans
  • heat shock factor-1, C elegans