Biology subjects

Casanellas, I.

Publications and source records attributed to Casanellas, I..

3 recordsLinked to original sources

bioRxiv2023

PIEZO1-HaloTag hiPSCs: Bridging Molecular, Cellular and Tissue Imaging

PIEZO1 is critical to numerous physiological processes, transducing diverse mechanical stimuli into electrical and chemical signals. Recent studies underscore the importance of visualizing endogenous PIEZO1 activity and localization to understand its functional roles. To enable physiologically and clinically relevant studies on human PIEZO1, we genetically engineered human induced pluripotent stem cells (hiPSCs) to express a HaloTag fused to endogenous PIEZO1. Combined with advanced imaging, our chemogenetic platform allows precise visualization of PIEZO1 localization dynamics in various cell types. Furthermore, the PIEZO1-HaloTag hiPSC technology facilitates the non-invasive monitoring of channel activity across diverse cell types using Ca2+-sensitive HaloTag ligands, achieving temporal resolution approaching that of patch clamp electrophysiology. Finally, we used lightsheet imaging of hiPSC-derived neural organoids to achieve molecular scale imaging of PIEZO1 in three-dimensional tissue organoids. Our advances offer a novel platform for studying PIEZO1 mechanotransduction in human cells and tissues, with potential for elucidating disease mechanisms and targeted therapeutic development.

biophysics↗

bioRxiv2022

Substrate adhesion determines migration during mesenchymal cell condensation in chondrogenesis

Effective cartilage development relies on the successful formation of mesenchymal cell condensates. Mesenchymal condensation is a prevalent morphogenetic transition, which involves the upregulation of the adhesive extracellular glycoprotein fibronectin (FN). During condensation, there is an active directional migration of cells from the surrounding loose mesenchyme towards regions of increasing matrix adherence (the condensation centers). In this study, we live imaged the first 40 h of mesenchymal condensation during chondrogenesis on nanopatterns of the cell-adhesive peptide arginine-glycine-aspartic acid (RGD), present in FN. Results show cell-substrate adhesions modulate both single-cell and collective cell migration during mesenchymal condensation. Single cell tracking analysis showed that substrate adhesion determines the migration mode, protrusion formation and the directionality of the cell movement. Cells on the more adhesive nanopatterns presented traits among amoeboid and mesenchymal modes of migration facilitating a more directional movement and reducing contact inhibition of locomotion (CIL), which allows merging and condensation. Inhibition experiments demonstrated that neural cadherin (N-Cad) is required in cell-cell interactions, enabling cells to coordinate their movement and directionality in a multicellular environment and to maintain the group cohesiveness during migration. Altogether, this contributes to create a sufficiently dynamic scenario, in which there is a balance between cell-substrate and cell-cell adhesions for condensates to grow. Our results provide a framework for the regulation of single and collective cell migration during mesenchymal condensation, through nanoscale cell-substrate adherence. Summary statementThe fine tuning of substrate adherence through nanopatterning allows control of mesenchymal cell migration and determines condensation during chondrogenesis in vitro.

biophysics↗

bioRxiv2021

Substrate ligand density modulates gap junction intercellular communication during mesenchymal cell condensation

To unveil the influence of cell-matrix adhesions in the establishment of gap junction intercellular communication (GJIC) during cell condensation in chondrogenesis. Materials & MethodsPreviously developed nanopatterns of the cell adhesive ligand arginine-glycine-aspartic acid (RGD) were used as cell culture substrates to control cell adhesion at the nanoscale. We conducted in vitro chondrogenesis of mesenchymal stem cells on the nanopatterns. We evaluated cohesion and GJIC in cell condensates. ResultsMechanical stability and GJIC are enhanced by a nanopattern configuration in which 90% of the surface area presents adhesion sites separated less than 70 nm, thus providing an onset for cell signaling. ConclusionCell-matrix adhesions regulate GJIC of mesenchymal cell condensates during in vitro chondrogenesis from a threshold configuration at the nanoscale.

bioengineering↗