Fig. 1
Preprocessing and processing framework of cytoskeletal analysis. (a) Results of the preprocessing pipeline are shown for immunofluorescence images of CHO cells with distinct morphologies. α-tubulin is stained in red and DAPI (blue) marked nuclei. Line segment arrangements and graph representations are shown for each preprocessed cell, with black dots as nodes and red pixelated paths as graph edges. (b) Schematic representation of Line Segment Features (LSFs) and Cytoskeleton Network Features (CNFs) analysed for each cell. LSFs, considering individual or close-by segments, were calculated using nuclei centroids as reference points. For each line \(\:i\), \(\:\left({x}_{i}^{1},{y}_{i}^{1}\right)\) and \(\:\left({x}_{i}^{2},{y}_{i}^{2}\right)\) represent the start and end points; \(\:{d}_{i}\) represents the distance to the i’th neighbour line; \(\:{\theta}_{i}\) is the angle with the horizontal axis; \(\:{L}_{i}\) is the length and \(\:{D}_{i}\) is the distance to the nucleus’ centroid, \(\:\left({x}_{N},{y}_{N}\right)\); \(\:{\alpha}_{i}\) represents the smallest angle between the line and the vector from a pixel \(\:\left({x}_{N},{y}_{N}\right)\) to line i. CNFs were extracted from the graph representation of the skeleton. Each square represents a pixel, whereas each edge \(\:i\) is a set of \(\:{n}_{j}\) adjacent pixels and \(\:{L}_{i}^{E}\) represents its total length.
