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ROSSIER, O.

Publications and source records attributed to ROSSIER, O..

2 recordsLinked to original sources

Remote Control of Cell Signaling through Caveolae Mechanics

Caveolae are invaginated plasma membrane nanodomains traditionally associated with membrane trafficking and signaling. These multifunctional organelles are also essential mechanosensors mediating the cell response to mechanical stress. We investigated the role of caveolae mechanics in regulating various signaling pathways. Single molecule imaging and super resolution microscopy revealed that mechanical stress rapidly triggers caveolae disassembly and the release of caveolin-1 scaffolds, which exhibit enhanced diffusion at the plasma membrane. This promoted direct interaction between the caveolin-1 scaffolding domain and the tyrosine kinase JAK1, leading to the inhibition of its catalytic activity. A similar process was observed for eNOS, PTEN, and PTP1B. Remote control of signaling by caveolae was validated by a theoretical model based on caveolae thermodynamics. These findings establish a novel mechanotransduction paradigm where signaling information is decoded remotely from the initial mechanosensing caveola, through dynamic and reversible assembly of tension-controlled complexes between signaling effectors and caveolin-1 scaffolds.

cell biology↗

Antigen self-anchoring onto bacteriophage T5 capsid-like particles for vaccine design

The promises of vaccines based on virus-like particles stimulate demand for universal non-infectious virus-like platforms that can be efficiently grafted with large antigens. Here we harnessed the modularity and extreme affinity of the decoration protein pb10 for the capsid of bacteriophage T5. SPR experiments demonstrated that pb10 fused to mCherry or to the model antigen ovalbumin (Ova) retained picomolar affinity for DNA-free T5 capsid-like particles (T5-CLPs), while cryo-EM studies attested to the full occupancy of the 120 capsid binding sites. Mice immunisation with CLP-bound pb10-Ova chimeras elicited strong long-lasting anti-Ova humoral responses involving a large panel of isotypes, as well as CD8+ T cell responses, without any extrinsic adjuvant. Therefore, T5-CLP constitutes the first DNA-free bacteriophage capsid able to irreversibly display a regular array of large antigens through highly efficient chemical-free anchoring. Its ability to elicit robust immune responses paves the way for further development of this novel vaccination platform.

immunology↗