Journal: Nat Commun / Year: 2022 Title: Elasticity of podosome actin networks produces nanonewton protrusive forces. Authors: Marion Jasnin / Jordan Hervy / Stéphanie Balor / Anaïs Bouissou / Amsha Proag / Raphaël Voituriez / Jonathan Schneider / Thomas Mangeat / Isabelle Maridonneau-Parini / Wolfgang Baumeister ...Authors: Marion Jasnin / Jordan Hervy / Stéphanie Balor / Anaïs Bouissou / Amsha Proag / Raphaël Voituriez / Jonathan Schneider / Thomas Mangeat / Isabelle Maridonneau-Parini / Wolfgang Baumeister / Serge Dmitrieff / Renaud Poincloux / Abstract: Actin filaments assemble into force-generating systems involved in diverse cellular functions, including cell motility, adhesion, contractility and division. It remains unclear how networks of actin ...Actin filaments assemble into force-generating systems involved in diverse cellular functions, including cell motility, adhesion, contractility and division. It remains unclear how networks of actin filaments, which individually generate piconewton forces, can produce forces reaching tens of nanonewtons. Here we use in situ cryo-electron tomography to unveil how the nanoscale architecture of macrophage podosomes enables basal membrane protrusion. We show that the sum of the actin polymerization forces at the membrane is not sufficient to explain podosome protrusive forces. Quantitative analysis of podosome organization demonstrates that the core is composed of a dense network of bent actin filaments storing elastic energy. Theoretical modelling of the network as a spring-loaded elastic material reveals that it exerts forces of a few tens of nanonewtons, in a range similar to that evaluated experimentally. Thus, taking into account not only the interface with the membrane but also the bulk of the network, is crucial to understand force generation by actin machineries. Our integrative approach sheds light on the elastic behavior of dense actin networks and opens new avenues to understand force production inside cells.
A: 15593.84 Å / B: 15593.84 Å / C: 2845.96 Å α=β=γ: 90.0 °
-
Supplemental data
-
Sample components
-
Entire : Podosomes assembled at the basal surface of an unroofed human pri...
Entire
Name: Podosomes assembled at the basal surface of an unroofed human primary monocyte-derived macrophage
Components
Organelle or cellular component: Podosomes assembled at the basal surface of an unroofed human primary monocyte-derived macrophage
-
Supramolecule #1: Podosomes assembled at the basal surface of an unroofed human pri...
Supramolecule
Name: Podosomes assembled at the basal surface of an unroofed human primary monocyte-derived macrophage type: organelle_or_cellular_component / ID: 1 / Parent: 0
Source (natural)
Organism: Homo sapiens (human)
-
Experimental details
-
Structure determination
Method
cryo EM
Processing
electron tomography
Aggregation state
cell
-
Sample preparation
Buffer
pH: 7.4
Grid
Model: Quantifoil / Material: GOLD / Support film - Material: CARBON / Support film - topology: HOLEY / Pretreatment - Type: GLOW DISCHARGE / Pretreatment - Atmosphere: AIR
Vitrification
Cryogen name: ETHANE
Details
Cells were unroofed prior to vitrification
Cryo protectant
No
Sectioning
Other: NO SECTIONING
Fiducial marker
Manufacturer: Aurion / Diameter: 10 nm
-
Electron microscopy
Microscope
FEI TITAN KRIOS
Specialist optics
Phase plate: VOLTA PHASE PLATE / Energy filter - Name: GIF Quantum LS / Energy filter - Slit width: 20 eV
Details
Bi-directional tilt series were acquired from -30 to +60 degrees and -32 to -60 degrees with a tilt increment of 2 degrees and Volta phase plates
Image recording
Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Detector mode: COUNTING / Average exposure time: 1.8 sec. / Average electron dose: 2.0 e/Å2
Electron beam
Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN
In the structure databanks used in Yorodumi, some data are registered as the other names, "COVID-19 virus" and "2019-nCoV". Here are the details of the virus and the list of structure data.
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)
EMDB accession codes are about to change! (news from PDBe EMDB page)
The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
The EM Navigator/Yorodumi systems omit the EMD- prefix.
Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator
Yorodumi is a browser for structure data from EMDB, PDB, SASBDB, etc.
This page is also the successor to EM Navigator detail page, and also detail information page/front-end page for Omokage search.
The word "yorodu" (or yorozu) is an old Japanese word meaning "ten thousand". "mi" (miru) is to see.
Related info.:EMDB / PDB / SASBDB / Comparison of 3 databanks / Yorodumi Search / Aug 31, 2016. New EM Navigator & Yorodumi / Yorodumi Papers / Jmol/JSmol / Function and homology information / Changes in new EM Navigator and Yorodumi