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ABSTRACT Cell migration requires the generation of branched actin networks that power the protrusion of the plasma membrane in lamellipodia1,2. The actin-related proteins 2 and 3 (Arp2/3)
complex is the molecular machine that nucleates these branched actin networks3. This machine is activated at the leading edge of migrating cells by Wiskott–Aldrich syndrome protein
(WASP)-family verprolin-homologous protein (WAVE, also known as SCAR). The WAVE complex is itself directly activated by the small GTPase Rac, which induces lamellipodia4,5,6. However, how
cells regulate the directionality of migration is poorly understood. Here we identify a new protein, Arpin, that inhibits the Arp2/3 complex _in vitro_, and show that Rac signalling recruits
and activates Arpin at the lamellipodial tip, like WAVE. Consistently, after depletion of the inhibitory Arpin, lamellipodia protrude faster and cells migrate faster. A major role of this
inhibitory circuit, however, is to control directional persistence of migration. Indeed, Arpin depletion in both mammalian cells and _Dictyostelium discoideum_ amoeba resulted in straighter
trajectories, whereas Arpin microinjection in fish keratocytes, one of the most persistent systems of cell migration, induced these cells to turn. The coexistence of the Rac–Arpin–Arp2/3
inhibitory circuit with the Rac–WAVE–Arp2/3 activatory circuit can account for this conserved role of Arpin in steering cell migration. Access through your institution Buy or subscribe This
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REGULATES MIGRATION PERSISTENCE THROUGH THE NHSL1-CONTAINING WAVE SHELL COMPLEX Article Open access 15 June 2023 NANCE-HORAN-SYNDROME-LIKE 1B CONTROLS MESODERMAL CELL MIGRATION BY REGULATING
PROTRUSION AND ACTIN DYNAMICS DURING ZEBRAFISH GASTRULATION Article Open access 28 February 2025 FORCES GENERATED BY LAMELLIPODIAL ACTIN FILAMENT ELONGATION REGULATE THE WAVE COMPLEX DURING
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PubMed Google Scholar Download references ACKNOWLEDGEMENTS A.G. acknowledges his PhD supervisor M. Arpin, the name of the here identified protein is a tribute to her mentoring. We thank G.
Romet-Lemonne, E. Portnoy and F. Marletaz for suggestions. We acknowledge support from Agence Nationale pour la Recherche (ANR-08-BLAN-0012-CSD 8 to A.G. and L.B., ANR-08-PCVI-0010-03 to
A.G., ANR-11-BSV8-0010-02 to A.G., J.C. and S.Z.-J.), Association pour la Recherche sur le Cancer (SFI20101201512 to A.G., PDF20111204331 to R.G., SFI20111203770 to N.B.D.), the
Bio-Emergences IBISA facility and Fundacao para a Ciencia e a Tecnologia (SFRH/BPD/46451/2008 to C.S.-B.), the Austrian Science Fund (FWF P21292-B09 to J.V.S.), the Deutsche
Forschungsgemeinschaft (FA 330/5-1 to J.F.) and grant number 8066, code 2012-1.1-12-000-1002-064 from the Russian Ministry of Education and Science to A.Y.A. AUTHOR INFORMATION Author notes
* Irene Dang, Roman Gorelik and Carla Sousa-Blin: These authors contributed equally to this work. AUTHORS AND AFFILIATIONS * Group Cytoskeleton in Cell Morphogenesis, Laboratoire
d’Enzymologie et Biochimie Structurales, CNRS UPR3082, Gif-sur-Yvette 91190, France, Irene Dang, Roman Gorelik, Carla Sousa-Blin, Emmanuel Derivery, Véronique Henriot, Violaine David, Ksenia
Oguievetskaia, Goran Lakisic, Fabienne Pierre & Alexis Gautreau * Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), Laboratoire de Physiologie Cellulaire et
Végétale, CNRS/CEA/INRA/UJF, Grenoble 38054, France, Christophe Guérin & Laurent Blanchoin * Institute for Biophysical Chemistry, Hannover Medical School, Hannover 30625, Germany, Joern
Linkner & Jan Faix * Institute of Molecular Biotechnology, Vienna 1030, Austria, Maria Nemethova & J. Victor Small * INSERM U1024, CNRS UMR8197, ENS, Institut de Biologie de l‘ENS,
Paris 75005, France, Julien G. Dumortier, Florence A. Giger & Nicolas B. David * Institute of Carcinogenesis, N. N. Blokhin Cancer Research Center, Russian Academy of Medical Sciences,
Moscow 115478, Russia, Tamara A. Chipysheva, Valeria D. Ermilova & Antonina Y. Alexandrova * Oncogenetic Laboratory, Institut Curie, Hôpital René Huguenin, Saint-Cloud 92210, France,
Sophie Vacher & Ivan Bièche * Group Small G Proteins, Laboratoire d’Enzymologie et Biochimie Structurales, CNRS UPR3082, Gif-sur-Yvette 91190, France, Valérie Campanacci, Anne-Gaelle
Planson, Susan Fetics & Jacqueline Cherfils * Laboratoire de Biologie Structurale et Radiobiologie (iBiTec-S), CNRS URA2096, CEA Saclay, Gif-sur-Yvette 91190, France, Isaline Herrada
& Sophie Zinn-Justin * Institute of Genetics, University of Bonn, Bonn 53115, Germany, Anika Steffen & Klemens Rottner * Institut des Systèmes Complexes & NeD, Institut de
Neurobiologie Alfred Fessard, CNRS UPR3294, Gif-sur-Yvette 91190, France, Adeline Boyreau & Nadine Peyriéras * Helmholtz Centre for Infection Research, Braunschweig 38124, Germany,
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I.D., R.G. and C.S.-B. performed videomicroscopy, analysed cell migration, analysed biochemical interactions of Arpin and its localization. E.D. wrote the bioinformatics programme that first
identified Arpin. C.G. and L.B. performed _in vitro_ actin polymerization and fluorescence anisotropy assays. J.L. and J.F. isolated knockout amoeba and analysed their migration. M.N. and
J.V.S. micro-injected fish keratocytes. J.G.D., F.A.G. and N.B.D characterized the Arpin phenotype in zebrafish. A.B. and N.P. determined the Arpin expression profile in zebrafish. I.H. and
S.Z.-J. contributed the NMR spectrum. T.A.C., V.D.E., A.Y.A., S.V., I.B., V.C., V.D., G.L., K.O., F.P., A.-G.P., S.F. and V.H. generated DNA constructs, isolated stable cell clones, purified
and characterized recombinant proteins, and performed crucial experiments for our understanding of Arpin function. A.S. and K.R. isolated the Rac1 knockout MEFs. All authors designed
experiments. N.P., K.R., S.Z.-J., J.C., N.B.D., I.B., A.Y.A., J.V.S., J.F., L.B. and A.G. supervised the work in their respective research group. A.G. coordinated the study and wrote the
paper. CORRESPONDING AUTHOR Correspondence to Alexis Gautreau. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing financial interests. EXTENDED DATA FIGURES AND TABLES
EXTENDED DATA FIGURE 1 PREDICTION OF SECONDARY STRUCTURE ELEMENTS AND DISORDERED REGIONS OF ARPIN. A multiple alignment of the Arpin orthologues was performed with MUSCLE41 and displayed
with Jalview42. Two methods relying on multiple alignments of Arpin orthologues were used to predict secondary structures and disordered regions, Psipred43 and Disopred44, respectively. The
predicted secondary structure (SS) elements are indicated by green arrows for β-strands, red cylinders for α-helices, and a black line for coils; the associated confidence (conf) score is
displayed below, ranging from 0 to 9 for poor and high confidence, respectively. Amino acid conservation is indicated by a 0 to 10 score, and highlighted by brown to yellow histogram bars.
The confidence in predicting disorder is also scored from 0 to 10, by multiplying tenfold the Disopred probability. Arpin is predicted to be a structured protein with the notable exception
of the 20 C-terminal residues, which are predicted to be disordered with high confidence. EXTENDED DATA FIGURE 2 NMR ANALYSIS OF 15N-LABELLED HUMAN ARPIN. Both views represent 1H–15N
heteronuclear single quantum coherence (HSQC) spectra. Each peak corresponds to the 1H–15N backbone amide bond of a specific residue. The position of a 1H–15N peak in the spectrum depends on
the chemical environment of the corresponding residue. A, Such a scattered distribution of peaks is characteristic of a folded protein. The last 20 residues were assigned to individual
peaks and are displayed on the spectrum. These residues are clustered in the centre of the spectrum. B, Same HSQC spectrum displayed with a higher threshold to display only high peaks. The
height of a peak depends on the mobility of the residue on a picosecond to millisecond timescale. This spectrum experimentally demonstrates that the 20 C-terminal residues are highly mobile.
This result confirms that, as predicted, the Arp2/3-binding site of Arpin is exposed as a poorly structured tail of the protein. EXTENDED DATA FIGURE 3 CHARACTERIZATION OF RECOMBINANT
ARPIN. A, Full-length Arpin or ArpinΔA from human or zebrafish cDNA was expressed in _E. coli_ and purified. Purity was assessed by SDS–PAGE and coomassie staining. These proteins were used
for _in vitro_ actin polymerization assays and for fish keratocyte injection, respectively. B, Analysis of the molar mass of full-length Arpins by size-exclusion chromatography coupled to
multiangle light scattering (SEC–MALS). The ultraviolet measurement (left axis, dashed line) and the molar mass (right axis, horizontal solid line) were plotted as a function of column
elution volume. C, SEC–MALS measures of masses indicate that both proteins are monomeric in solution. D, GST pull-down using a lysate of 293 cells overexpressing PC-tagged Arpin and purified
GST–Rac1 wild type, GST–Rac1(Gln61Leu) or GST alone as a negative control. Arpin did not associate with either type of Rac. By contrast, the endogenous WAVE complex bound to Rac(Gln61Leu),
but not Rac wild type, as expected from a Rac effector. E, Untagged Rac1 was purified from _E. coli_ and then loaded with either GDP or GTPγS. Human Arpin (60 μM), Rac1 (120 μM) and mixture
of these two proteins were analysed by SEC–MALS as above. SEC was run in 20 mM HEPES, 100 mM NaCl, pH 7.4. The height of ultraviolet peaks was normalized to 1 to be displayed on the same
figure. A single peak was detected in all cases. The measured masses indicate that no complex is formed between Arpin and Rac and that the single peak observed in the mixture corresponds to
cofractionation of the two proteins of similar mass by SEC. EXTENDED DATA FIGURE 4 ARPIN DIRECTLY BINDS TO THE ARP2/3 COMPLEX. A, Fluorescence anisotropy measurements of labelled ArpinA
peptide binding at equilibrium to the purified Arp2/3 complex at the indicated concentrations. B, Labelled ArpinA peptide bound to the Arp2/3 complex was then titrated with purified Arpin
full-length, ArpinΔA or unlabelled ArpinA peptide as indicated. Full-length Arpin displaces the labelled ArpinA peptide more efficiently than the A peptide. ArpinΔA is unable to displace the
ArpinA peptide. Curves that best fit the values yield the indicated equilibrium constants. C, Arpin inhibits Arp2/3 activation in the pyrene-actin assay. Part of this experiment is
displayed in Fig. 1c, more curves are plotted here. D, From curves in C, the number of actin barbed ends is calculated from the slope at half-polymerization using the relationship described
previously45. Best fit of the values indicate an apparent _K_d value of 760 ± 156 nM for the Arp2/3 complex in a mixture including actin and the VCA. E, ArpinA inhibits Arp2/3 activation in
a dose dependent manner in the pyrene-actin assay. Conditions: 2 μM actin (10% pyrene-labelled), 500 nM VCA, 20 nM Arp2/3 and ArpinA at the indicated concentrations. F, ArpinA competes with
the NPF for Arp2/3 binding. Arp2/3 is displaced from its interaction with 5 μM GST N-WASP VCA immobilized on glutathione beads by the Arpin acidic peptide (304 μM and serial twofold
dilutions). EXTENDED DATA FIGURE 5 SPECIFIC LOCALIZATION OF ARPIN AT THE LAMELLIPODIUM TIP. A, Arpin overlaps with the Arp2/3 complex at the lamellipodium tip. B, Arpin overlaps with
cortactin at the lamellipodium tip. Arpin staining is lost after short interfering RNA (siRNA)-mediated depletion. Intensity profiles along multiple line scans encompassing the cell
periphery were registered to the outer edge of the staining of a lamellipodial marker. This marker was Arpin in A and cortactin in B. The multiple line scans were then averaged and displayed
as an intensity plot, where the _y_ axis represents fluorescent intensity, arbitrary units (mean ± s.e.m., _n_ = 17, 16 and 17, respectively). Scale bar, 20 μm. Arp2/3 localization extends
rearwards relative to Arpin localization. This result is because the Arp2/3 complex becomes a branched junction when activated by the WAVE complex at the lamellipodium tip. The branched
junction undergoes retrograde flow like actin itself due to actin filament elongation9,12. Cortactin recognizes Arp2/3 at the branch junction and is thought to stabilize branched actin
networks13. As a marker of the branched junction, cortactin stains the width of lamellipodia, like the Arp2/3 complex. C, Rac1 knockout MEFs that lack lamellipodia14 are completely devoid of
Arpin staining at the cell periphery, in line with the complete absence of lamellipodia indicated here by the absence of cortactin staining. Arpin is normally expressed in the Rac1 knockout
MEFs (see Fig. 2c). Intensity profiles along multiple line scans encompassing the cell periphery were averaged after manual drawing of the cell edge (mean ± s.e.m., _n_ = 16). Scale bar, 20
μm. EXTENDED DATA FIGURE 6 ARPIN REGULATES CELL SPREADING THROUGH ITS INTERACTION WITH THE ARP2/3 COMPLEX. Arpin was depleted from human RPE1 cells after transient transfection of shRNA
plasmids and blasticidin-mediated selection of transfected cells. After 5 days, cells were either analysed by western blot or used for the spreading assay. Cells were serum-starved for 90
min in suspension in polyHEMA-coated dishes and then allowed to spread on collagen-I-coated coverslips for 2 h. Phalloidin staining was used to calculate cell surface area of individual
cells using ImageJ. Mean ± s.e.m.; **_P_ < 0.01, ***_P_ < 0.001; _t_-test or ANOVA when more than two conditions. A, Arpin depletion increases cell spreading (_n_ = 57 and 52,
respectively). The same effect is obtained with three shRNAs targeting Arpin (_n_ = 51, 48 and 59, respectively). B, This effect is rescued by GFP–Arpin expression in knockdown cells, but
not by GFP–ArpinΔA expression(_n_ = 63, 56, 63 and 52, respectively). C, Combined depletion of Arpin and the Arp2/3 complex reverses the phenotype of Arpin depletion. The effect is seen with
two shRNAs targeting ArpC2 (_n_ = 56, 60, 69, 68, 63 and 66, respectively). The last two experiments indicate that Arpin exerts its effect on cell spreading through its ability to regulate
the Arp2/3 complex. EXTENDED DATA FIGURE 7 ARPIN REGULATES PROTRUSION FREQUENCY OF PRECHORDAL PLATE CELLS AND THEIR COLLECTIVE MIGRATION IN ZEBRAFISH EMBRYOS. A, _In situ_ hybridization of
_arpin_ probe in zebrafish embryos at different stages. _arpin_ mRNAs are maternally deposited. During gastrulation, _arpin_ is expressed in hypoblast, which includes the prechordal plate.
B, Three-dimensional trajectories of prechordal plate cells in embryos injected with control or _arpin_ morpholino. During fish gastrulation, prechordal plate cells migrate collectively in a
straight direction from the margin of the embryo towards the animal pole38,46. Loss of _arpin_ function induces dispersion as evidenced by increased lateral cell displacement (_n_ = 1,516
and 1,546) and a higher distance between cells (_n_ = 194 and 235). Lateral displacement is the cell movement perpendicular to main direction of the migration. Distance between cells refers
to the average distance of the nucleus of a given cell to the nuclei of its five closest neighbours. Mean ± s.e.m.; ***_P_ < 0.001, _t_-test. C, At the onset of gastrulation prechordal
plate cells derived from morpholino injected embryos were transplanted into the prechordal plate of an untreated host embryo at the same stage in order to allow imaging of cell autonomous
effects on protrusion formation. Donor embryos are injected with control or _arpin_ morpholinos and mRNAs encoding Lifeact-mCherry as well as GFP–Arpin for the rescue. Time-lapse imaging of
injected cells is performed by epifluorescence to reveal Lifeact, a marker of filamentous actin, which stains actin-based protrusions. For each cell, presence of a protrusion was assessed at
each frame to deduce probability of protrusion presence and protrusion lifetimes. _arpin_ loss of function increases the probability of presence of protrusions (_n_ = 8, 8 and 10,
respectively; *_P_ < 0.05, ANOVA) and their duration (in this case, _n_ corresponds to the number of protrusions (_n_ = 42, 41 and 40, respectively; *_P_ < 0.05, Kruskal–Wallis).
Protrusions are indicated by arrowheads. Scale bar, 50 μm. EXTENDED DATA FIGURE 8 ARPIN DEPLETION INCREASES CELL MIGRATION IN THREE DIMENSIONS. Stable MDA-MB-231 clones depleted of Arpin or
not were embedded in a collagen gel. A, Single-cell trajectories illustrate that control cells hardly move in this dense environment (see Supplementary Video 4), unlike Arpin-depleted cells,
which explore a significant territory, albeit at lower pace than in two dimensions, as evidenced by mean square displacement (Extended Data Fig. 9). B, Cell speed is significantly increased
in the Arpin-depleted clones. Mean ± s.e.m.; _n_ = 27, 25, 26 and 17, respectively, *_P_ < 0.05, Kruskal–Wallis, two experiments. Directional persistence, calculated by _d_/_D_, is not
significantly different in the clones depleted of Arpin or not. Direction autocorrelation (Extended Data Fig. 10), however, shows an increased directionality in the Arpin-depleted cells at
the earliest time points. EXTENDED DATA FIGURE 9 ANALYSIS OF MEAN SQUARE DISPLACEMENT OF THE DIFFERENT MIGRATION EXPERIMENTS. The mean square displacement gives a measure of the area
explored by cells for any given time interval. By setting a positional vector on the cellular trajectory at time _t_, the MSD is defined as: , in which brackets indicate averages over all
starting times _t_0 and all cells _N._ For each time interval Δtime, mean and s.e.m. are plotted. Error bars corresponding to s.e.m. are plotted, even if too small to be visible. The grey
area excludes the noisy part of curves corresponding to large time intervals where less data points are available. A, MDA-MB-231 depleted or not of Arpin in a two- or three-dimensional
environment. Arpin-depleted MDA-MB-231 cells explore a larger territory than the controls in time intervals examined (for two dimensions, _n_ as indicated in Fig. 3a; _P_ < 0.001, two-way
ANOVA with time and conditions; for three dimensions, _n_ as indicated in Extended Data Fig. 8; _P_ < 0.001, two-way ANOVA with time and conditions). B, _Dictyostelium discoideum_
knockout amoebae explore a larger territory than controls and rescued amoebae (_n_ as indicated in Fig. 3b, _P_ < 0.001, two-way ANOVA with time and conditions). C, Arpin-injected fish
keratocytes explore a smaller territory than the controls (_n_ as indicated in Fig. 4b; _P_ < 0.001, two-way ANOVA with time and conditions). EXTENDED DATA FIGURE 10 ANALYSIS OF DIRECTION
AUTOCORRELATION OF THE DIFFERENT MIGRATION EXPERIMENTS. A, Principle of the analysis. A hypothetical cell trajectory is depicted. Each step is represented by a vector of normalized length.
_θ_ is the angle between compared vectors. The plot illustrates the cos_θ_ values for the putative trajectory of four steps (colour-coded). Averaging these cos_θ_ values yields the direction
autocorrelation (DA) function of time that measures the extent to which these vectors are aligned over different time intevals. The DA function is defined as: , in which _Υ_(_t_0) is the
vector at the starting time _t_0, and _Υ_(_t_0 + _t_) the vector at _t_0 + _t_. Brackets indicate that all calculated cosines are averaged for all possible starting times (_t_0) over all
cells (_N_). For each time interval _t_, vectors from all cell trajectories were used to compute average and sem. Error bars corresponding to s.e.m. are plotted, even if too small to be
visible. B, Arpin-depleted MDA-MB-231 clones turn less than control cells (for two dimensions, _n_ as indicated in Fig. 3a; _P_ < 0.05 between 10 and 40 min, Kruskal–Wallis; for three
dimensions, _n_ as indicated in Extended Data Fig. 8; _P_ < 0.05 at time 10 min, Kruskal–Wallis). C, Arpin knockout amoebae turn less than wild-type amoebae, and GFP–Arpin overexpressing
knockout amoebae (rescue) turn more than wild type (_n_ as indicated in Fig. 3b; _P_ < 0.05 between 5 and 85 s, Kruskal–Wallis). E, Arpin-injected fish keratocytes turn more than
buffer-injected cells, and ArpinΔA-injected keratocytes turn more than buffer-injected but less than full-length-Arpin-injected keratocytes (_n_ as indicated in Fig. 4b; _P_ < 0.05
between 16 and 272 s, Kruskal–Wallis). SUPPLEMENTARY INFORMATION ARPIN INHIBITS THE FORMATION OF BRANCHED ACTIN NETWORKS BY THE ARP2/3 COMPLEX 1 µM actin, 150 nM VCA, 80 nM Arp2/3 and Arpin
at 5 µM when indicated. TIRF microscopy. Scale bar : 30 µm and 5 µm in the inset. (AVI 3294 kb) ARPIN DEPLETION INCREASES THE SPEED OF LAMELLIPODIAL PROTRUSIONS RPE1 cells were recorded with
one phase contrast image every 3 s for 10 min (using a Plan Apochromat 63x/1.40 oil immersion objective) while spreading on collagen I coated dish (Ibidi) in serum free medium. Scale bar: 3
µm. The insets showing lamellipodial protrusions are magnified 4-fold. (AVI 3559 kb) _ARPIN_ LOSS OF FUNCTION INCREASES PROTRUSION LIFETIME OF ZEBRAFISH PRECHORDAL PLATE CELLS. At the onset
of gastrulation, prechordal plate cells derived from morpholino injected embryos were transplanted into the prechordal plate of an untreated host embryo at the same stage. Donor embryos are
injected with control or arpin morpholinos and mRNAs encoding Lifeact-mCherry as well as GFP-Arpin for the rescue. Z-stacks were recorded every 30 seconds. Protrusion lifetime was measured
from the appearance of the protrusion (green arrowhead) to its retraction (red arrowhead). Scale bar: 20 µm. (AVI 486 kb) ARPIN DEPLETION INCREASES MIGRATION OF MDA-MB-231 CELLS Stable Arpin
knock-down cells were compared to control cells. Cells were allowed to spread on fibronectin-coated 8 well µ-slide (Ibidi) for 2 h, before imaging for 24 h with an image every 10 min using
phase contrast and a Plan-Apochromat 20x/0.80 air objective. Scale bar : 50 µm. (AVI 3164 kb) ARPIN DEPLETION INCREASES MIGRATION OF MDA-MB-231 CELLS IN 3D Stable Arpin knock-down cells were
compared to control cells. Cells were sandwiched between two 3D collagen gels so as to have most cells in a single plane of view at the beginning of movie acquistion. Cells were imaged for
48 h with an image every 20 min using phase contrast and a Plan-Apochromat 20x/0.80 air objective. Scale bar: 50 µm. (AVI 2668 kb) ARPIN KNOCK-OUT INCREASES MIGRATION OF _DICTYOSTELIUM
DISCOIDEUM_ KO amoeba were compared to wild type and KO re-expressing GFP-DdArpin. Amoeba were imaged onto 3 cm glass-bottom dishes (Matek) in Soerensen-phosphate buffer (17 mM
Na/K-phosphatebuffer, pH 6.1) for 15 min with an image every 5 s using phase contrast or green fluorescence and a UPlanFL 10x NA 0.3 objective. Scale bar : 40 µm. (AVI 861 kb) ARPIN
MICROINJECTION INTO FISH KERATOCYTES INDUCES LAMELLIPODIUM INSTABILITY AND CELL TURNING Keratocytes were imaged with phase contrast optics at x63 magnification with one frame every 8 s for
10 minutes. They were microinjected at the time 24 s. Scale bar: 10 µm. (AVI 1964 kb) ARPIN MICROINJECTION INTO FISH KERATOCYTES INDUCES CYCLES OF PROTRUSION AND RETRACTION OF THE
LAMELLIPODIUM This video shows the same kymograph as fig. 4c but corrected from cell movement. To register the video to the cell rather than to the substratum, fiduciary marks within the
cell nucleus were manually tracked and the reverse movement was applied to the entire image using a custom imageJ macro. A kymograph on the corrected video was then generated along the white
line using imageJ. This video highlights the oscillatory behavior of the leading edge upon Arpin microinjection. Scale bar: 10µm. (AVI 2512 kb) POWERPOINT SLIDES POWERPOINT SLIDE FOR FIG. 1
POWERPOINT SLIDE FOR FIG. 2 POWERPOINT SLIDE FOR FIG. 3 POWERPOINT SLIDE FOR FIG. 4 SOURCE DATA SOURCE DATA TO FIG. 1 RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE
THIS ARTICLE Dang, I., Gorelik, R., Sousa-Blin, C. _et al._ Inhibitory signalling to the Arp2/3 complex steers cell migration. _Nature_ 503, 281–284 (2013).
https://doi.org/10.1038/nature12611 Download citation * Received: 21 November 2012 * Accepted: 28 August 2013 * Published: 16 October 2013 * Issue Date: 14 November 2013 * DOI:
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