The Structure of Cilium Inner Junctions Revealed by Electron Cryo-tomography DOI Creative Commons
Sam Li, José‐Jesús Fernández, Marisa D. Ruehle

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 9, 2024

The cilium is a microtubule-based organelle critical for many cellular functions. Its assembly initiates at basal body and continues as an axoneme that projects out of the cell to form functional cilium. This process tightly regulated. However, our knowledge molecular architecture mechanism limited. By applying electron cryo-tomography subtomogram averaging, we obtained subnanometer resolution structures inner junction in three distinct regions cilium: proximal region body, central core flagellar axoneme. allowed us identify several components. While few proteins are distributed throughout entire length organelle, restricted particular cilium, forming intricate local interaction networks bolstering structural stability. Finally, by knocking component Poc1, found triplet MT was destabilized, resulting defective structure. Surprisingly, axoneme-specific components were "infiltrate" into mutant body. Our findings provide insight its junctions, underscoring precise spatial regulation.

Language: Английский

Time-series reconstruction of the molecular architecture of human centriole assembly DOI Creative Commons
Marine H. Laporte, Davide Gambarotto, Éloïse Bertiaux

et al.

Cell, Journal Year: 2024, Volume and Issue: 187(9), P. 2158 - 2174.e19

Published: April 1, 2024

Language: Английский

Citations

30
An interaction network of inner centriole proteins organised by POC1A-POC1B heterodimer crosslinks ensures centriolar integrity DOI Creative Commons

Carol Davies Sala,

Martin Würtz, Enrico Salvatore Atorino

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Nov. 14, 2024

Abstract Centriole integrity, vital for cilia formation and chromosome segregation, is crucial human health. The inner scaffold within the centriole lumen composed of proteins POC1B, POC5 FAM161A key to this integrity. Here, we provide an understanding function proteins. We demonstrate importance interaction network organised by POC1A-POC1B heterodimers lumen, where WD40 domain POC1B localises close wall, while POC5-interacting POC1A resides in lumen. POC1A-POC5 tetramerization are essential stability. microtubule binding MDM1 POC1A-POC1B, likely positioning tetramer near wall. Disruption or leads defects deletion both genes causes disintegration. These findings insights into organisation scaffold.

Language: Английский

Citations

7
A ternary complex of MIPs in the A-tubule of basal bodies and axonemes depends on RIB22 and the EF-hand domain of RIB72A in Tetrahymena cilia DOI
Rachel A. Howard-Till, Sam Li,

Usha Pallabi Kar

et al.

Molecular Biology of the Cell, Journal Year: 2025, Volume and Issue: 36(4)

Published: Feb. 12, 2025

The lumens of the highly stable microtubules that make up core basal bodies, cilia, and flagella are coated with a network proteins known as MIPs, or microtubule inner proteins. MIPs hypothesized to enhance rigidity stability these microtubules, but how they assemble contribute cilia function is poorly understood. Here we describe ciliate specific MIP, RIB22, in Tetrahymena thermophila. RIB22 calmodulin-like protein found A-tubule doublet triplet bodies. Its localization dependent on conserved MIP RIB72. use cryogenic electron tomography (cryoET) examine its interacting partners axonemes forms ternary complex C-terminal EF-hand domain RIB72A another FAM166A. strains lacking showed impaired function. CryoET from demonstrated an interdependence three for stabilization within structure. Deletion resulted apparent loss multiple region. These findings emphasize intricacy importance understanding MIPs’ functions during cilium assembly regulation.

Language: Английский

Citations

0
The structure of basal body inner junctions from Tetrahymena revealed by electron cryo-tomography DOI Creative Commons
Sam Li, José‐Jesús Fernández, Marisa D. Ruehle

et al.

The EMBO Journal, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 24, 2025

Abstract The cilium is a microtubule-based eukaryotic organelle critical for many cellular functions. Its assembly initiates at basal body and continues as an axoneme that projects out of the cell to form functional cilium. This process tightly regulated. However, our knowledge molecular architecture mechanism limited. By applying cryo-electron tomography, we obtained structures inner junction in three regions from Tetrahymena : proximal, central core body, axoneme. We identified several protein components body. While few proteins are distributed throughout entire length organelle, restricted specific regions, forming intricate local interaction networks bolstering structural stability. examining POC1 knockout mutant, found triplet microtubule was destabilized, resulting defective structure. Surprisingly, axoneme-specific were “infiltrate” into mutant Our findings provide insight junctions, underscoring its precise spatial regulation.

Language: Английский

Citations

0
The A-C Linker controls centriole cohesion and duplication DOI Creative Commons
Lorène Bournonville, Marine H. Laporte,

Susanne Borgers

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 4, 2024

Abstract Centrioles are evolutionarily conserved barrel-shaped organelles playing crucial roles in cell division and ciliogenesis. These functions underpinned by specific structural sub-elements whose have been under investigation since many years. The A- C linker structure, connecting adjacent microtubule triplets the proximal region, has remained unexplored due to its unknown composition. Here, using ultrastructure expansion microscopy, we characterized two recently identified A-C proteins, CCDC77 WDR67, along with a newly discovered protein, MIIP. Our findings reveal that these proteins localize between at linker, forming complex. Depletion of components disrupt triplet cohesion, leading breakage end. Co-removal inner scaffold demonstrates their joint role maintaining centriole architecture. Moreover, uncover an unexpected function duplication through torus regulation, underscoring interplay protein modules.

Language: Английский

Citations

2
The Structure of Cilium Inner Junctions Revealed by Electron Cryo-tomography DOI Creative Commons
Sam Li, José‐Jesús Fernández, Marisa D. Ruehle

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 9, 2024

The cilium is a microtubule-based organelle critical for many cellular functions. Its assembly initiates at basal body and continues as an axoneme that projects out of the cell to form functional cilium. This process tightly regulated. However, our knowledge molecular architecture mechanism limited. By applying electron cryo-tomography subtomogram averaging, we obtained subnanometer resolution structures inner junction in three distinct regions cilium: proximal region body, central core flagellar axoneme. allowed us identify several components. While few proteins are distributed throughout entire length organelle, restricted particular cilium, forming intricate local interaction networks bolstering structural stability. Finally, by knocking component Poc1, found triplet MT was destabilized, resulting defective structure. Surprisingly, axoneme-specific components were "infiltrate" into mutant body. Our findings provide insight its junctions, underscoring precise spatial regulation.

Language: Английский

Citations

1