ZFIN ID: ZDB-PUB-120702-38
Knockdown of ttc26 disrupts ciliogenesis of the photoreceptor cells and the pronephros in zebrafish
Zhang, Q., Liu, Q., Austin, C., Drummond, I., and Pierce, E.A.
Date: 2012
Source: Molecular biology of the cell   23(16): 3069-3078 (Journal)
Registered Authors: Drummond, Iain
Keywords: none
MeSH Terms:
  • Animals
  • Cell Line
  • Cilia/physiology*
  • Gene Knockdown Techniques
  • Larva/cytology
  • Male
  • Mice
  • Morpholinos/genetics
  • Phenotype
  • Photoreceptor Cells/cytology*
  • Photoreceptor Cells/metabolism
  • Pronephros/cytology*
  • Pronephros/metabolism
  • Protein Transport
  • RNA Interference
  • Rats
  • Zebrafish*
  • Zebrafish Proteins/genetics*
  • Zebrafish Proteins/metabolism
PubMed: 22718903 Full text @ Mol. Biol. Cell

In our effort to understand genetic disorders of the photoreceptors cells of the retina we have focused on intraflagellar transport in photoreceptor sensory cilia. From previous mouse proteomic data we identified a cilia protein Ttc26, ortholog of dyf-13 in C. elegans, as a target. We have localized Ttc26 to the transition zone of photoreceptor and to the transition zone of cilia in cultured mIMCD3 renal cells. Knockdown of Ttc26 in mIMCD3 cells produced shortened and defective primary cilia, revealed by immunofluorescence and scanning EM respectively. To study Ttc26 function in sensory cilia in vivo, we utilized a zebrafish vertebrate model system. Morpholino knockdown of ttc26 in zebrafish embryos caused cilia defects in the pronephric kidney at 27 hpf and distension/dilation of pronephros at 5 dpf. In the eyes, the outer segments of photoreceptor cells appeared shortened or absent, whereas cellular lamination appeared normal in retinas at 5 dpf. This suggests that loss of ttc26 function prevents normal ciliogenesis and differentiation in the photoreceptor cells, and that ttc26 is required for normal development and differentiation in retina and pronephros. Our studies support the importance of Ttc26 function in ciliogenesis and suggest that screening for TTC26 mutations in human ciliopathies is justified.