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Plak, K.

Publications and source records attributed to Plak, K..

3 recordsLinked to original sources

High-Throughput Mechanomic Screening Reveals Novel Regulators of Single-Cell Mechanics

The mechanical properties of cells are dynamic, allowing them to adjust to different needs in different biological contexts. In recent years, advanced biophysical techniques have enabled the rapid, high-throughput assessment of single-cell mechanics, providing new insights into the regulation of the mechanical cell phenotype. However, the molecular mechanisms by which cells maintain and regulate their mechanical properties remain poorly understood. Here, we present a genome-scale RNA interference (RNAi) screen investigating the roles of kinase and phosphatase genes in regulating single-cell mechanics using Real-Time Fluorescence and Deformability Cytometry (RT-FDC). Our screen identified 80 known and novel mechanical regulators across diverse cellular functions from 214 targeted genes, leveraging RT-FDCs unique capabilities for comprehensive, high-throughput mechanical phenotyping with single-cell and cell cycle resolution. These findings refine our understanding of how signaling pathways coordinate structural determinants of cell mechanical phenotypes and provide a starting point for uncovering new molecular targets involved in biomechanical regulation across diverse biological systems. SIGNIFICANCECell mechanical properties are tightly regulated and play pivotal roles in processes ranging from tissue morphogenesis to disease progression. Despite their importance, the genetic regulation of single-cell mechanics remains largely unexplored. This study represents one of only a few large-scale mechanomic investigations conducted to date. It is the first study to leverage RT-FDCs unique capability for high-throughput mechanical phenotyping with single-cell and cell cycle resolution to detect gene impacts that may be overlooked in lower-throughput or population-level studies. The mechanical genes identified here provide valuable data points for understanding how cells control their mechanical state and serve as a foundation for future studies exploring the molecular basis of biomechanical regulation.

biophysics↗

Oncogenic signaling alters cell shape and mechanics to facilitate cell division under confinement.

When cells enter mitosis, they become spherical and mechanically stiffen. We used MCF10A cell lines as a model system in which to investigate the effect of induced oncogene expression on mitotic entry. We find that activation of oncogenic RasV12, for as little as five hours, changes the way cells divide. RasV12-dependent activation of the MEK-ERK signalling cascade alters acto-myosin contractility to enhance mitotic rounding. RasV12 also affects cell mechanics, so that RasV12 expressing cells are softer in interphase but stiffen more upon entry into mitosis. As a consequence, RasV12 expression augments the ability of cells to round up and divide faithfully when confined underneath a stiff hydrogel. Conversely, inhibition of the Ras-ERK pathway reduces mitotic rounding under confinement, resulting in chromosome segregation defects. These data suggest a novel mechanism by which oncogenic Ras-ERK signalling can aid division in stiff environments like those found in tumours.

cell biology↗

Real-time fluorescence and deformability cytometry - flow cytometry goes mechanics

Cell mechanical characterization has recently approached the throughput of conventional flow cytometers. However, this very sensitive, label-free approach still lacks the specificity of molecular markers. Here we combine real-time 1D-imaging fluorescence and deformability cytometry (RT-FDC) to merge the two worlds in one instrument -- opening many new research avenues. We demonstrate its utility using sub-cellular fluorescence localization to identify mitotic cells and test for their mechanical changes in an RNAi screen.

biophysics↗