Fig. 1: Spatial distribution, algorithm and CellDetail.
From: Quantitative determination of the spatial distribution of components in single cells with CellDetail
a The level of polarity of the distribution of a component in a cell can adopt multiple distinct states and can thus be regarded as a continuous variable. b HSC with a polar distribution of the protein Cdc42 (red) (left: schematic, right: confocal IF image and bright field (BF), scale bar = 5 µm). c Left top: Equation to calculate the dipole moment (polarity) of chemical molecules. Left low: H2O is a highly polar molecule, while CO2 is a highly apolar molecule. (δ = charges, R = charge centers, d = distance, green arrow, P = dipole moment). Right top: Equation to calculate the dipole moment of a component within a cell (q = charges, R = charge centers, d = distance, green arrow, P = dipole moment). Charge centers of the red component in the cell are shown as red (positive charge center) and blue (negative charge center) crosses. d Sequential steps for quantifying polarity via the value Pn as output parameter in 3D IF images. e Example calculation of Pn for the protein Cdc42 in HSC (here single 2D layer). Step1 shows the conversion of intensity values into charge values by subtracting the average cell intensity, step2 shows the charge-weighted barycenters. More detail on these steps can be found in Supplementary F Algorithm. (ii) Pn is calculated based on the (i) normalized charge (qn1) and the normalized distance (Rn1) between the charge centers. f Output parameters of CellDetail: (i) polarity quantification, (ii) amount of the biomolecule, (iii) spatial volume of biomolecule, (iv) vectors between middle of cell and positive/negative charge-weighted centers, (v) grade of constriction of biomolecule charge centers, (vi) Pearson correlation analyses (RPearson) for inter-biomolecule behavior analyses. g Examples of z-stacks (3D) of HSCs visually apolar and polar for the distribution of the protein Cdc42 in HSCs (out of 14 apolar and 23 polar used in (h)). h Histogram of Pn values for the protein Cdc42 for 14 HSCs visually apolar for Cdc42 and 23 HSCs visually polar for Cdc42. Source data are provided as a Source Data file.
