Dataset Information

Proteomic analysis of microtubule inner proteins (MIPs) in Rib72 null Tetrahymena cells reveals functional MIPs.

ABSTRACT: The core structure of motile cilia and flagella, the axoneme, is built from a stable population of doublet microtubules. This unique stability is brought about, at least in part, by a network of microtubule inner proteins (MIPs) that are bound to the luminal side of the microtubule walls. Rib72A and Rib72B were identified as MIPs in the motile cilia of the protist Tetrahymena thermophila. Loss of these proteins leads to ciliary defects and loss of additional MIPs. We performed mass spectrometry coupled with proteomic analysis and bioinformatics to identify the MIPs lost in RIB72A/B knockout Tetrahymena axonemes. We identified a number of candidate MIPs and pursued one, Fap115, for functional characterization. We find that loss of Fap115 results in disrupted cell swimming and aberrant ciliary beating. Cryo-electron tomography reveals that Fap115 localizes to MIP6a in the A-tubule of the doublet microtubules. Overall, our results highlight the complex relationship between MIPs, ciliary structure, and ciliary function.

SUBMITTER: Fabritius AS

PROVIDER: S-EPMC8693976 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Proteomic analysis of microtubule inner proteins (MIPs) in Rib72 null <i>Tetrahymena</i> cells reveals functional MIPs.

Fabritius Amy S AS Bayless Brian A BA Li Sam S Stoddard Daniel D Heydeck Westley W Ebmeier Christopher C CC Anderson Lauren L Gunnels Tess T Nachiappan Chidambaram C Whittall Justen B JB Old William W Agard David A DA Nicastro Daniela D Winey Mark M

Molecular biology of the cell 20210818 21

The core structure of motile cilia and flagella, the axoneme, is built from a stable population of doublet microtubules. This unique stability is brought about, at least in part, by a network of microtubule inner proteins (MIPs) that are bound to the luminal side of the microtubule walls. Rib72A and Rib72B were identified as MIPs in the motile cilia of the protist <i>Tetrahymena thermophila</i>. Loss of these proteins leads to ciliary defects and loss of additional MIPs. We performed mass spectr ...[more]

PMID: 34406789

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Dataset Information

Proteomic analysis of microtubule inner proteins (MIPs) in Rib72 null Tetrahymena cells reveals functional MIPs.

Publications

Proteomic analysis of microtubule inner proteins (MIPs) in Rib72 null <i>Tetrahymena</i> cells reveals functional MIPs.

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