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Custom Analysis Part 4

Renske van Raaphorst edited this page Oct 18, 2019 · 2 revisions

Plot the average localization per division

For snap-shot data, I am used to making demographs: localization plots based on cell length. For time-lapses, it can also be very useful to combine the data of all cells together, but instead of cell length, I’d rather use cell division. To be able to do this,perc_Division() takes the cell division time of each cell as a percentage of division where 0== cell birth, and 100 equals the point where the cell produces 2 daughter cells. In this way, it is possible to combine and plot all cells, no matter their size or growth speed, based on their division.

To make a kymograph based on division percentage, first combine the dataset we just made, cells_custom, with the dataset containing the TIFF image, image_custom, so the pixel values are connected to the cell information.

cells_image <- extr_OriginalCells(image_custom, cells_custom)

Now, I can use bactKymo() to plot the fluorescence over division. bactKymo() has the option percDiv. When put to TRUE, the cell fluorescence will be binned per division percentage.

bactKymo(cells_image$rawdata_turned, timeD=TRUE, percDiv=TRUE, sizeAV=TRUE, mag="100x_DVMolgen")

Check by eye

Even though I already discarded non-growing cells & cells with a too-short division time, I decided to go through the kymographs and see if the quality of the kymographs is high enough. I only selected on growth using perc_Division(), but there also might be cells without detectable fluorescence, or wrongly segmented cells, and I see no other way to check for these than by eye, unfortunately. To do this as well, save the PDF of seperate kymographs again:

cairo_pdf(filename="Kymos_cluster.pdf", onefile=TRUE)

bactKymo(cells_image$rawdata_turned, timeD=TRUE, sizeAV=TRUE, mag="100x_DVMolgen")

dev.off()

Based on this, I selected a group of cells to discard. Some cells did not grow, some have a very low fluorescence, and some only have fluorescence on the edge of the cell. I saved their cell numbers in classification_eye.csv. For the tutorial, I suggest you do your own selection (or if you wish, skip this step below).

Discard cells

I remove the cells from cells_custom and cells_image:

class_eye <- read.csv("Fig5D-H/classification_eye.csv", header=TRUE)

cells_custom <- cells_custom[!cells_custom$cell%in%class_eye$cell,]
cells_image$rawdata_turned <- cells_image$rawdata_turned[!cells_image$rawdata_turned$cell%in%class_eye$cell,]

⬅️ Custom Analysis Part 3: Filtering the Data Custom Analysis Part 5: Preparation for Cluster Analysis ➡️
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