ZFIN ID: ZDB-PUB-080527-11
The intraflagellar transport protein IFT57 is required for cilia maintenance and regulates IFT-particle-kinesin-II dissociation in vertebrate photoreceptors
Krock, B.L., and Perkins, B.D.
Date: 2008
Source: Journal of Cell Science   121(Pt 11): 1907-1915 (Journal)
Registered Authors: Perkins, Brian
Keywords: Retinal degeneration, Opsin trafficking, Zebrafish
MeSH Terms:
  • Adaptor Proteins, Signal Transducing/genetics
  • Adaptor Proteins, Signal Transducing/metabolism*
  • Animals
  • Carrier Proteins/genetics
  • Carrier Proteins/metabolism
  • Cilia/metabolism*
  • Cilia/ultrastructure
  • Kinesin/metabolism*
  • Microscopy, Electron, Transmission
  • Mutation/genetics*
  • Phenotype
  • Photoreceptor Cells/abnormalities
  • Photoreceptor Cells/metabolism*
  • Photoreceptor Cells/ultrastructure
  • Protein Transport/genetics
  • Rod Opsins/metabolism
  • Tumor Suppressor Proteins/genetics
  • Tumor Suppressor Proteins/metabolism
  • Zebrafish
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism*
PubMed: 18492793 Full text @ J. Cell Sci.
Defects in protein transport within vertebrate photoreceptors can result in photoreceptor degeneration. In developing and mature photoreceptors, proteins targeted to the outer segment are transported through the connecting cilium via the process of intraflagellar transport (IFT). In studies of vertebrate IFT, mutations in any component of the IFT particle typically abolish ciliogenesis, suggesting that IFT proteins are equally required for IFT. To determine whether photoreceptor outer segment formation depends equally on individual IFT proteins, we compared the retinal phenotypes of IFT57 and IFT88 mutant zebrafish. IFT88 mutants failed to form outer segments, whereas IFT57 mutants formed short outer segments with reduced amounts of opsin. Our phenotypic analysis revealed that IFT57 is not essential for IFT, but is required for efficient IFT. In co-immunoprecipitation experiments from whole-animal extracts, we determined that kinesin II remained associated with the IFT particle in the absence of IFT57, but IFT20 did not. Additionally, kinesin II did not exhibit ATP-dependent dissociation from the IFT particle in IFT57 mutants. We conclude that IFT20 requires IFT57 to associate with the IFT particle and that IFT57 and/or IFT20 mediate kinesin II dissociation.