Oscillatory dynamics of Rac1 activity in Dictyostelium discoideum amoebae

PLoS Computational Biology, Год журнала: 2024, Номер 20(12), С. e1012025 - e1012025

Опубликована: Дек. 9, 2024

Small GTPases of the Rho family play a central role in regulation cell motility by controlling remodeling actin cytoskeleton. In amoeboid cells Dictyostelium discoideum, active form GTPase Rac1 regulates polymerases at leading edge and filament bundling proteins posterior cortex polarized cells. We monitored spatiotemporal dynamics its effector DGAP1 vegetative amoebae using specific fluorescent probes. observed that plasma membrane domains enriched not only exhibited stable polarization, but also showed rotations oscillations, whereas was depleted from these regions. To simulate two proteins, we developed mass-conserving reaction-diffusion model based on circulation between cytoplasm coupled with activation GEFs, deactivation GAPs interaction DGAP1. Our theoretical accurately reproduced experimentally dynamic patterns, including predominant anti-correlation Significantly, predicted new colocalization regime cells, which confirmed experimentally. summary, our results improve understanding reveal how occurrence transitions different regimes depend biochemical reaction rates, protein levels size. This study expands knowledge behavior D. discoideum demonstrates modes lead to their counterintuitively anti-correlated dynamics.

Язык: Английский

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Self-organization of PIP3 signaling is controlled by the confinement, topology, and curvature of the cell membrane

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Янв. 23, 2024

PIP3 is a signaling lipid on the plasma membrane that plays fundamental role in cell with strong impact physiology and diseases. It responsible for protruding edge formation, polarization, macropinocytosis other remodeling dynamics cells. has been shown confinement curvature affects wave formation of Factin. But even absence F-actin, complex self-organization spatiotemporal waves observed. In recent findings, we have these can be guided pinned strongly bended Dictyostelium membranes caused by molecular crowding limited diffusion. Based experimental investigate realist 3D cell-like to explore effect diffusion, as observed experimentally. We use an established stochastic reaction-diffusion model enzymatic MichaelisMenten type reactions mimics As cells mimic shape size experimentally, found directionality explained Hopf-like reverse periodic-doubling bifurcation uniform diffusion properties. Finally, compare results findings discuss discrepancy between biological numerical results.

Язык: Английский

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Cell morphogenesis via self-propelled treadmilling actin waves

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Фев. 28, 2024

SUMMARY Actin dynamics mediate cell morphogenesis. filaments polymerize outward at protrusions such as the leading edge of migrating cells, thereby pushing membrane to protrude. The current paradigm explains that actin are regulated by signaling. However, it is unclear how cells spontaneously form actin-based even without a specific local signaling cue. We found arrays treadmilling emerge widely in and move direction polymerization waves. Their arrival periphery pushes plasma Furthermore, they accumulate cues, similar self-propelled particles colliding with boundary. This leads further growth protrusions, promoting spontaneous formation for migration. propose waves drive robust morphogenesis, through their abilities self-accumulate into push membrane.

Язык: Английский

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Emergence of rogue-like waves in a reaction-diffusion system: Stochastic output from deterministic dissipative dynamics

Chaos An Interdisciplinary Journal of Nonlinear Science, Год журнала: 2024, Номер 34(5)

Опубликована: Май 1, 2024

Rogue waves are an intriguing nonlinear phenomenon arising across different scales, ranging from ocean through optics to Bose-Einstein condensates. We describe the emergence of rogue wave-like dynamics in a reaction-diffusion system that arise as result subcritical Turing instability. This state is present regime where all time-independent states unstable and consists intermittent excitation spatially localized spikes, followed by collapse subsequent regrowth. characterize spatiotemporal organization spikes show sufficiently large domains consistent with memoryless process.

Язык: Английский

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A Hands-on Guide to AmoePy — a Python-Based Software Package to Analyze Cell Migration Data

Methods in molecular biology, Год журнала: 2024, Номер unknown, С. 159 - 184

Опубликована: Янв. 1, 2024

Язык: Английский

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