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The intraflagellar transport protein, IFT88, is essential for vertebrate photoreceptor assembly and maintenance.

ABSTRACT: Approximately 10% of the photoreceptor outer segment (OS) is turned over each day, requiring large amounts of lipid and protein to be moved from the inner segment to the OS. Defects in intraphotoreceptor transport can lead to retinal degeneration and blindness. The transport mechanisms are unknown, but because the OS is a modified cilium, intraflagellar transport (IFT) is a candidate mechanism. IFT involves movement of large protein complexes along ciliary microtubules and is required for assembly and maintenance of cilia. We show that IFT particle proteins are localized to photoreceptor connecting cilia. We further find that mice with a mutation in the IFT particle protein gene, Tg737/IFT88, have abnormal OS development and retinal degeneration. Thus, IFT is important for assembly and maintenance of the vertebrate OS.

SUBMITTER: Pazour GJ

PROVIDER: S-EPMC2173265 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

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The intraflagellar transport protein, IFT88, is essential for vertebrate photoreceptor assembly and maintenance.

Pazour Gregory J GJ Baker Sheila A SA Deane James A JA Cole Douglas G DG Dickert Bethany L BL Rosenbaum Joel L JL Witman George B GB Besharse Joseph C JC

The Journal of cell biology 20020326 1

Approximately 10% of the photoreceptor outer segment (OS) is turned over each day, requiring large amounts of lipid and protein to be moved from the inner segment to the OS. Defects in intraphotoreceptor transport can lead to retinal degeneration and blindness. The transport mechanisms are unknown, but because the OS is a modified cilium, intraflagellar transport (IFT) is a candidate mechanism. IFT involves movement of large protein complexes along ciliary microtubules and is required for assemb ...[more]

PMID: 11916979

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Cluap1 is essential for ciliogenesis and photoreceptor maintenance in the vertebrate eye.

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Binding of IFT22 to the intraflagellar transport complex is essential for flagellum assembly

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Control of vertebrate intraflagellar transport by the planar cell polarity effector Fuz.

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