Publications associées à Architecture of the centriole cartwheel‐containing region revealed by cryo‐electron tomography

Microsecond Time-Resolved Cryo-Electron Microscopy

Recently, single-particle cryo-electron microscopy emerged as a technique capable of determining protein structures at near-atomic resolution and resolving protein dynamics with a temporal resolution ranging from second to milliseconds. This thesis describ ...

EPFL2024

New roles of Bicc1 in cilia formation, cell adhesion, and in adult kidneys

Céline Gagnieux

Bicaudal-C1 (Bicc1), an RNA-Binding protein, is a ciliopathy-associated protein. In development, Bicc1 is necessary for left-right axis specification. Loss of Bicc1 in mice also associates with polycystic kidney development. In human, two hereditary polycy ...

EPFL2023

AAV9-mediated SMN gene therapy rescues cardiac desmin but not lamin A/C and elastin dysregulation in Smn(2B/-) spinal muscular atrophy mice

Bernard Schneider

Structural, functional and molecular cardiac defects have been reported in spinal muscular atrophy (SMA) patients and mouse models. Previous quantitative proteomics analyses demonstrated widespread molecular defects in the severe Taiwanese SMA mouse model. ...

Oxford University Press2023

Sperm-contributed centrioles segregate stochastically into blastomeres of 4-cell stage Caenorhabditis elegans embryos

Pierre Gönczy, Fernando Romero Balestra

Whereas both sperm and egg contribute nuclear genetic material to the zygote in metazoan organisms, the inheritance of other cellular constituents is unequal between the 2 gametes. Thus, 2 copies of the centriole are contributed solely by the sperm to the ...

GENETICS SOCIETY AMERICA2023

In Situ and Time-Resolved Transmission Electron Microscopy of Nanoscale Processes

Chengcheng Yan

Observing the fast dynamics of nanoscale systems is crucial in order to understand and ultimately control their behavior. Characterizing these dynamic processes requires techniques with atomic spatial resolution and a temporal resolution that matches the t ...

EPFL2023

Dissecting centriole fate in C. elegans development

Nils Kalbfuss

The presence of centrioles is critical for fundamental cell and developmental processes, including polarity, migration and division. Although centrioles are present in most proliferating cells, they are thought to vanish after cell cycle exit in some diffe ...

EPFL2022

Structures of SAS-6 coiled coil hold implications for the polarity of the centriolar cartwheel

Pierre Gönczy, Georgios Hatzopoulos

Centrioles are eukaryotic organelles that template the formation of cilia and flagella, as well as organize the microtubule network and the mitotic spindle in animal cells. Centrioles have proximal-distal polarity and a 9 fold radial symmetry imparted by a ...

CELL PRESS2022

Tuning SAS-6 architecture with monobodies impairs distinct steps of centriole assembly

Tatiana Favez, Pierre Gönczy, Virginie Hamel, Santiago Harald Andany, Georg Fantner, Oliver Hantschel, Georgios Hatzopoulos, Niccolo Banterle

Centrioles are evolutionarily conserved multi-protein organelles essential for forming cilia and centrosomes. Centriole biogenesis begins with self-assembly of SAS-6 proteins into 9-fold symmetrical ring polymers, which then stack into a cartwheel that sca ...

Nature Research2021

Visualizing intracellular nanostructures of living cells by nanoendoscopy-AFM

Marcos Penedo Garcia

Atomic force microscopy (AFM) is the only technique that allows label-free imaging of nanoscale biomolecular dynamics, playing a crucial role in solving biological questions that cannot be addressed by other major bioimaging tools (fluorescence or electron ...

AMER ASSOC ADVANCEMENT SCIENCE2021

Rapid melting and revitrification as an approach to microsecond time-resolved cryo-electron microscopy

Marcel Drabbels, Ulrich Lorenz, Pavel Olshin, Jonathan Mark Voss, Oliver Florian Harder

Proteins typically undergo dynamics on the microsecond to millisecond timescale, which is much faster than the time resolution of cryo-electron microscopy. Here, we propose a novel approach for microsecond time-resolved cryo-electron microscopy that involv ...

Elsevier2021

A helical inner scaffold provides a structural basis for centriole cohesion

Henning Paul-Julius Stahlberg, Virginie Hamel, Paul Guichard, Davide Gambarotto

The ninefold radial arrangement of microtubule triplets (MTTs) is the hallmark of the centriole, a conserved organelle crucial for the formation of centrosomes and cilia. Although strong cohesion between MTTs is critical to resist forces applied by ciliary ...

2020

Novel features of centriole polarity and cartwheel stacking revealed by cryo-tomography

Pierre Gönczy, Davide Demurtas, Alexandra Bezler, Sergey Nazarov, Paul Guichard, Veronika Nemcíková Villímová, Georgios Hatzopoulos

Centrioles are polarized microtubule-based organelles that seed the formation of cilia, and which assemble from a cartwheel containing stacked ring oligomers ofSAS-6 proteins. A cryo-tomography map of centrioles from the termite flagellateTrichonymphaspp. ...

2020

Centriole foci persist in starfish oocytes despite Polo-like kinase 1 inactivation or loss of microtubule nucleation activity

Pierre Gönczy, Marie Juliette Ségolène Pierron, Nils Kalbfuss

Centrioles must be eliminated or inactivated from the oocyte to ensure that only the two functional centrioles contributed by the sperm are present in the zygote. Such removal can occur during oogenesis, as in Drosophila, where departure of Polo kinase fro ...

2020

Reconstruction Methods for Cryo-Electron Microscopy: From Model-based to Data-driven

Laurène Donati

The topic of this thesis is the development of new reconstruction methods for cryo-electron microscopy (cryo-EM). Cryo-EM has revolutionized the field of structural biology over the last decade and now permits the regular discovery of biostructures. Yet, t ...

EPFL2020

Centriole assembly at a glance

Pierre Gönczy, Georgios Hatzopoulos

The centriole organelle consists of microtubules (MTs) that exhibit a striking 9-fold radial symmetry. Centrioles play fundamental roles across eukaryotes, notably in cell signaling, motility and division. In this Cell Science at a Glance article and accom ...

2019

Flagellar microtubule doublet assembly in vitro reveals a regulatory role of tubulin C-terminal tails

Davide Demurtas, Virginie Hamel, Paul Guichard

Microtubule doublets (MTDs), consisting of an incomplete B-microtubule at the surface of a complete A-microtubule, provide a structural scaffold mediating intraflagellar transport and ciliary beating. Despite the fundamental role of MTDs, the molecular mec ...

American Association for the Advancement of Science2019

Structure and transformation of bacteriophage A511 baseplate and tail upon infection of Listeria cells

Petr Leiman, Sergey Nazarov, Ricardo Cesar Guerrero Ferreira

Contractile injection systems (bacteriophage tails, type VI secretions system, R-type pyocins, etc.) utilize a rigid tube/contractile sheath assembly for breaching the envelope of bacterial and eukaryotic cells. Among contractile injection systems, bacteri ...

WILEY2019

Protein Engineering Tools to Explore the Function of Protein Post-Translational Modifications for Chromatin and Microtubule Cytoskeletal Biology

Ninad Dilip Agashe

Protein post-translational modifications (PTMs) play a crucial role in expanding the protein diversity and are one of the major mechanisms through which cells respond to ever changing environmental cues. The function of two of the most important cellular c ...

EPFL2019

Live imaging screen reveals that TYRO3 and GAK ensure accurate spindle positioning in human cells

Pierre Gönczy, Coralie Busso, Benita Wolf

Proper spindle positioning is crucial for spatial cell division control. Spindle positioning in human cells relies on a ternary complex comprising G alpha i1-3, LGN and NuMA, which anchors dynein at the cell cortex, thus enabling pulling forces to be exert ...

Springer2019

Integrative approach to analyze the proximal region of the Trichonympha agilis centriole

Veronika Nemcíková Villímová

The centrosome, the major microtubule organizing center in animal cells, is composed of two orthogonally arranged centrioles and surrounding pericentriolar material. Centrioles are evolutionary conserved organelles characterized by a nine-fold symmetry of ...

EPFL2018