Persistent cell migration emerges from a coupling between protrusion dynamics and polarized trafficking

Abstract

Migrating cells present a variety of paths, from non-persistent random walks to highly directional trajectories. While random movement can be easily explained by an intrinsic basal activity of the cell, persistent movement requires the cell to be stably polarized. It remains unclear how this is achieved from the regulation of underlying subcellular processes. In the context of mesenchymal migration, the ability of cells to migrate persistently over several hours require a mechanism stabilizing their protruding activity at their front. Here, we address this mechanism using human RPE1 cell line as our model. We measure, manipulate, and quantitatively perturb cell protrusive activity of the cortex as well as intracellular organization of the endomembrane trafficking system using dynamic micropatterning, pharmacological and trafficking assays, optogenetics and live-cell imaging with tracking. First, we demonstrate that the Nucleus-Golgi axis aligns with the direction of migration and its alignment with the protrusive activity leads to efficient cell movement. Then, using low doses of Nocodazole to disrupt internal cell organization, we show that long-lived polarity breaks down and migration becomes random. Next, we indicate that a flow of vesicles is directed towards the protrusive activity with a delay of 20 min. Eventually, by applying a sustained optogenetic activation, we prove that a localized Cdc42 gradient is able to orient the Nucleus-Golgi axis over a couple of hours. Taken together, our results suggest that the internal polarity axis, provided by the polarized trafficking of vesicles, is stabilizing the protrusive activity of the cell, while the protrusive activity biases this polarity axis. Using a novel minimal physical model, we show that this feedback is sufficient by itself to recapitulate the quantitative properties of cell migration in the timescale of hours. Our work highlights the importance of the coupling between high-level cellular functions in stabilizing the direction of migration over long timescales.

Optogenetic control of a GEF of RhoA uncovers a signaling switch from retraction to protrusion

“…Up to now, the optogenetic approaches that have been developed to control GTPases in space and time tended to confirm the canonical picture. For example, we and others have shown that for Rac1 and Cdc42, despite of a complex cross-activation, the recruitment at the plasma membrane of minimal GEF activating domains causally induce cell protrusions 9 and migration led by the front 10 . Along the same line, optogenetic approaches to control RhoA, reviewed in 11 and 12 , have all shown a causal induction of cell retraction.…”

Advances in Regulating Cellular Behavior Using Micropatterns

“…Luo et al [114] produced UV functionalized TiO 2 nanorods micropattern in various configurations, including concentric, linear, honeycomb-like, square, and gem-like stripes (each with a width of 30 µm) and demonstrated Nucleus-Golgi axis [96] as factors associated with cell polarization.…”

iLID-antiGFP-nanobody is a flexible targeting strategy for recruitment to GFP-tagged proteins

“…These experiments require overexpression of the signaling molecules fused to SspB but also the target protein, which by itself might already have a signaling effect. iLID is widely used and often in combination with a plasma membrane tag (Dessauges et al, 2022; Gonzalez-Martinez et al, 2022; Saha et al, 2022; Vaidžiulytė et al, 2022). The approach can be improved by targeting proteins to a more specific location, for example recruiting to focal adhesions or adherens junctions where local GEF and GAP activity have been detected (Müller et al, 2020).…”