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Molecular basis of tubulin transport within the cilium by IFT74 and IFT81.

ABSTRACT: Intraflagellar transport (IFT) of ciliary precursors such as tubulin from the cytoplasm to the ciliary tip is involved in the construction of the cilium, a hairlike organelle found on most eukaryotic cells. However, the molecular mechanisms of IFT are poorly understood. Here, we found that the two core IFT proteins IFT74 and IFT81 form a tubulin-binding module and mapped the interaction to a calponin homology domain of IFT81 and a highly basic domain in IFT74. Knockdown of IFT81 and rescue experiments with point mutants showed that tubulin binding by IFT81 was required for ciliogenesis in human cells.

SUBMITTER: Bhogaraju S

PROVIDER: S-EPMC4359902 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Molecular basis of tubulin transport within the cilium by IFT74 and IFT81.

Bhogaraju Sagar S Cajanek Lukas L Fort Cécile C Blisnick Thierry T Weber Kristina K Taschner Michael M Taschner Michael M Mizuno Naoko N Lamla Stefan S Bastin Philippe P Nigg Erich A EA Lorentzen Esben E

Science (New York, N.Y.) 20130801 6149

Intraflagellar transport (IFT) of ciliary precursors such as tubulin from the cytoplasm to the ciliary tip is involved in the construction of the cilium, a hairlike organelle found on most eukaryotic cells. However, the molecular mechanisms of IFT are poorly understood. Here, we found that the two core IFT proteins IFT74 and IFT81 form a tubulin-binding module and mapped the interaction to a calponin homology domain of IFT81 and a highly basic domain in IFT74. Knockdown of IFT81 and rescue exper ...[more]

PMID: 23990561

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