Biophysical Modelling
Cellular ageing of oral fibroblasts differentially modulates extracellular matrix organization
Ageing is associated with an impaired cellular function that can affect tissue architecture and wound healing in gingival and periodontal tissues. However, the impact of oral fibroblast ageing on the structural organization of the extracellular matrix (ECM) proteins is poorly understood. Hence, in this study, we investigated the impact of cellular ageing of oral fibroblasts on the production and structural organization of collagen and other ECM proteins.
ReadPhosphatase POPX2 interferes with cell cycle by interacting with Chk1
Protein–protein interaction network analysis plays critical roles in predicting the functions of target proteins. In this study, we used a combination of SILAC-MS proteomics and bioinformatic approaches to identify Checkpoint Kinase 1 (Chk1) as a possible POPX2 phosphatase interacting protein.
ReadRegulation of flagellar motor switching by c-di-GMP phosphodiesterases in Pseudomonas aeruginosa
The second messenger cyclic diguanylate (c-di-GMP) plays a prominent role in regulating flagellum-dependent motility in the single-flagellated pathogenic bacterium Pseudomonas aeruginosa. The c-di-GMP–mediated signaling pathways and mechanisms that control flagellar output remain to be fully unveiled. Studying surface-tethered and free-swimming P. aeruginosa PAO1 cells, we found that the overexpression of an exogenous diguanylate cyclase (DGC) raises the global cellular c-di-GMP concentration and thereby inhibits flagellar motor switching and decreases motor speed, reducing swimming speed and reversal frequency, respectively.
ReadEnrichment and Identification of Neural Stem Cells in Neurospheres Using Rigidity-Tunable Gels
Neural stem cells (NCSs) are integral to establishing in vitro models and regenerative medicine. To this day, there is an unmet need to enrich these cells from a heterogeneous cell population for clinical applications without irreversible manipulation. We identified a method to propagate human NCSs via computational analysis of their mechanical signature.
ReadSuperresolution microscopy reveals distinct localisation of full length IRSp53 and its I-BAR domain protein within filopodia
Superresolution microscopy offers the advantage of imaging biological structures within cells at the nano-scale. Here we apply two superresolution microscopy techniques, specifically 3D structured illumination microscopy (3D-SIM) and direct stochastic optical reconstruction microscopy (dSTORM), a type of single molecule localisation microscopy, to localise IRSp53 protein and its I-BAR domain in relation to F-actin within filopodia.
ReadAnisotropic traction stresses and focal adhesion polarization mediates topography-induced cell elongation
Cell elongation and differentiation has been shown to be modulated by topographical cues provided by grating substratum. However, little is known about the mechanisms and forces involved in the grating-induced cell elongation, due to the difficulty in fabricating soft elastic gels that allow 3-dimensional (3D) cell traction stress measurements.
ReadEnhanced Delta-Notch Lateral Inhibition Model Incorporating Intracellular Notch Heterogeneity and Tension-Dependent Rate of Delta-Notch Binding that Reproduces Sprouting Angiogenesis Patterns
Endothelial cells adopt unique cell fates during sprouting angiogenesis, differentiating into tip or stalk cells. The fate selection process is directed by Delta-Notch lateral inhibition pathway. Classical Delta-Notch models produce a spatial pattern of tip cells separated by a single stalk cell, or the salt-and-pepper pattern. However, classical models cannot explain alternative tip-stalk patterning, such as tip cells that are separated by two or more stalk cells.
ReadThree-dimensional computational model of multiphase flow driven by a bed of active cilia
Micro-scale physiological fluid propulsion is often accomplished with arrays of beating cilia. It is well-known that cilia can spontaneously coordinate their beat patterns to form metachronal waves. While it is generally agreed upon that metachronal waves arise largely due to hydrodynamic coupling, their effects on fluid propulsion are not thoroughly explored. There are presently complex, nonlinear models where cilia motion mimics their internal mechanisms; however these models are often computationally challenging and expensive to perform.
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