Journal: bioRxiv

Article Title: Polarity and mixed-mode oscillations may underlie different patterns of cellular migration

doi: 10.1101/2022.10.31.514611

Figure Lengend Snippet: Characteristics of inactive and active classes of CHO-K1 cells exhibiting two distinct migration patterns detected using the α -value. (a, b) Representative binary masks (left) illustrating the shapes of CHO-K1 cells, along with their representative migration tracks (right). (c) Roseplots of a sample of CHO-K1 cell tracks (31 in total) colour-coded according to each class; orange: inactive, blue: active. (d) Time series of the level of membrane activity of two representative CHO-K1 cells, colour-coded according to each class. (e) Mean α -value of CHO-K1 cells in each class. (f) Directionality ratio (DR) for the entire trajectory of CHO-K1 cells in each class. (g) Mean instantaneous speed of CHO-K1 cells in each class. (h) Multiple measurements of the level of membrane activity, in term of pixel counts, of CHO-K1 cells in each class. Error bars indicate SEM. Black dots represent individual cells. Tracking data from were used to produce panels c, e, f and g. Tracking data and cell images acquired for this study were used to produce panels a, b, d and h. There were n = 18 inactive cells and n = 108 active cells in panels e, f and g, whereas there were n=3 inactive and n=4 active cells in panel h.

Article Snippet: Stable cell lines expressing paxillin-S273A-EGFP or paxillin-S273D-EGFP were based on ATCC purchased CHO-K1 cells.

Techniques: Migration, Activity Assay

Journal: bioRxiv

Article Title: Polarity and mixed-mode oscillations may underlie different patterns of cellular migration

doi: 10.1101/2022.10.31.514611

Figure Lengend Snippet: Periods of directedness and directionality change in active CHO-K1 and oscillating CPM cells. Event detection framework applied to (a) an active CHO-K1 cell, and (b) an oscillating CPM cell. Directionality ratio (left panels), computed using a rolling window of length 60 minutes (light blue) for an active CHO-K1 cell and 20 time steps for an oscillating CPM cells, allowed for event detection (orange dots). Superimposing detected events (orange dots) on cell tracks (right panel) shows a good agreement with directionality change.

Article Snippet: Stable cell lines expressing paxillin-S273A-EGFP or paxillin-S273D-EGFP were based on ATCC purchased CHO-K1 cells.

Techniques:

Journal: bioRxiv

Article Title: Polarity and mixed-mode oscillations may underlie different patterns of cellular migration

doi: 10.1101/2022.10.31.514611

Figure Lengend Snippet: Serine-273 (S273) residue on paxillin is key to CHO-K1 cell migration. Roseplots showing cell tracks (n=40 cells for each condition) of wild-type CHO-K1 cells that were transfected with (a) paxillin-EGFP, (b) paxillin-S273A-EGFP phosphomutant, and (c) paxillin-S273D-EGFP phosphomimic. (d) Mean instantaneous speed of the same sampled cells in each condition, measured over 360 minute-long recordings. (e) Mean α -value of the same sampled cells in each condition, computed using a rolling window of length 60 minutes. (f) Normalized number of events of the same sampled cells in each condition computed over their entire tracks. Error bars indicate SEM. Cell tracking data from were used to produce the figure.

Article Snippet: Stable cell lines expressing paxillin-S273A-EGFP or paxillin-S273D-EGFP were based on ATCC purchased CHO-K1 cells.

Techniques: Migration, Transfection, Cell Tracking Assay

Journal: bioRxiv

Article Title: Polarity and mixed-mode oscillations may underlie different patterns of cellular migration

doi: 10.1101/2022.10.31.514611

Figure Lengend Snippet: Machine classification of CHO-K1 cell tracks in three different condition. Tracks of 40 CHO-K1 cells expressing (a) paxillin-S273A-EGFP mutant, (b) wild-type-paxillin-EGFP, or (c) paxillin-S273D-EGFP mutant. Trajectories were colour-coded based on the classifier’s predictions with green corresponding to tracks classified as cells expressing the S273A mutant, orange as wild-type and purple as the S273D mutant. Insets: boxplots showing the distributions of the classifier’s predictions within each class. Tracking data from were used to produce the figure.

Article Snippet: Stable cell lines expressing paxillin-S273A-EGFP or paxillin-S273D-EGFP were based on ATCC purchased CHO-K1 cells.

Techniques: Expressing, Mutagenesis

Journal: bioRxiv

Article Title: Polarity and mixed-mode oscillations may underlie different patterns of cellular migration

doi: 10.1101/2022.10.31.514611

Figure Lengend Snippet: Image processing of motile cells. (a) A widefield fluorescence microscopy image of a CHO-K1 cell expressing WT-paxillin-EGFP. Such images often have a light halo and noisy background, that are (b) filtered to obtain a high signal-to-noise image, and then (c) thresholded to generate a binary image and detect the entire cell body by applying the ”find-particle” Fiji/ImageJ plug-in, resulting in (d) a binary mask of the cell. For the CPM cell, the binary masks in step d are generated directly without the need for the first three steps a-c because, by definition, the simulated images have pixels with signal and pixels that have no signal.

Article Snippet: Stable cell lines expressing paxillin-S273A-EGFP or paxillin-S273D-EGFP were based on ATCC purchased CHO-K1 cells.

Techniques: Fluorescence, Microscopy, Expressing, Generated