EMD-29685
48-nm doublet microtubule from Tetrahymena thermophila strain CU428
EMD-29685
Single-particle4.1 Å
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Map released: 14/06/2023
Last modified: 25/12/2024
Sample Organism:
Tetrahymena thermophila,
Tetrahymena thermophila
Sample: 48-nm repeat unit of microtubule doublet from Tetrahymena thermophila strain CU428
Fitted models: 8g2z
Deposition Authors: Black CS
,
Kubo S
,
Yang SK
,
Bui KH
Sample: 48-nm repeat unit of microtubule doublet from Tetrahymena thermophila strain CU428
Fitted models: 8g2z
Deposition Authors: Black CS
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Native doublet microtubules from Tetrahymena thermophila reveal the importance of outer junction proteins.
Kubo S
,
Black CS
,
Joachimiak E
,
Yang SK
,
Legal T,
Peri K,
Khalifa AAZ,
Ghanaeian A
,
McCafferty CL
,
Valente-Paterno M,
De Bellis C,
Huynh PM,
Fan Z,
Marcotte EM
,
Wloga D,
Bui KH
(2023) Nat Commun , 14 , 2168 - 2168
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(2023) Nat Commun , 14 , 2168 - 2168
Abstract:
Cilia are ubiquitous eukaryotic organelles responsible for cellular motility and sensory functions. The ciliary axoneme is a microtubule-based cytoskeleton consisting of two central singlets and nine outer doublet microtubules. Cryo-electron microscopy-based studies have revealed a complex network inside the lumen of both tubules composed of microtubule-inner proteins (MIPs). However, the functions of most MIPs remain unknown. Here, we present single-particle cryo-EM-based analyses of the Tetrahymena thermophila native doublet microtubule and identify 42 MIPs. These data shed light on the evolutionarily conserved and diversified roles of MIPs. In addition, we identified MIPs potentially responsible for the assembly and stability of the doublet outer junction. Knockout of the evolutionarily conserved outer junction component CFAP77 moderately diminishes Tetrahymena swimming speed and beat frequency, indicating the important role of CFAP77 and outer junction stability in cilia beating generation and/or regulation.
Cilia are ubiquitous eukaryotic organelles responsible for cellular motility and sensory functions. The ciliary axoneme is a microtubule-based cytoskeleton consisting of two central singlets and nine outer doublet microtubules. Cryo-electron microscopy-based studies have revealed a complex network inside the lumen of both tubules composed of microtubule-inner proteins (MIPs). However, the functions of most MIPs remain unknown. Here, we present single-particle cryo-EM-based analyses of the Tetrahymena thermophila native doublet microtubule and identify 42 MIPs. These data shed light on the evolutionarily conserved and diversified roles of MIPs. In addition, we identified MIPs potentially responsible for the assembly and stability of the doublet outer junction. Knockout of the evolutionarily conserved outer junction component CFAP77 moderately diminishes Tetrahymena swimming speed and beat frequency, indicating the important role of CFAP77 and outer junction stability in cilia beating generation and/or regulation.