New automatized approach for image processing in Xenopus laevis oocytes

GUASTAFERRI, FLORENCIA; OZU, MARCELO; GIBSON, OLIVER; AMODEO, GABRIELA; CAVIGLIA, AGUSTÍN FRANCISCO; GALIZIA, LUCIANO

Ciudad Autónoma de Buenos Aires

Jornada; Jornadas Virtuales de la Sociedad Argentina de Biofísica; 2020

Sociedad Argentina de Biofísica

Xenopus laevis oocytes is a cellular model used widely for aquaporin and ion channel heterologous expression. This cellular model allows us to record sequential images or videos with low-cost videomicroscopy equipment (Dorr et al., 2007). Our group developed different acquisition devices to study various aspects of the aquaporin functionality (Ozu et al., 2005). Although this model allows us to obtain data from thousands of oocytes from each donor, one bottleneck in the experimental workflow is image processing. Timelapses recorded at high temporal resolution (e.g., 30 fps), may contain thousands of images where cell/oocyte volume information must be extracted. The traditional processing of those images is performed manually, using free software (e.g., ImageJ) to segment the oocyte and to evaluate oocyte volume assuming high circularity criteria. Oocyte segmentation is user-dependent and requires training and experimental criteria. Then, information about the oocyte area in each image is converted to a relative volume curve. Water osmotic permeability coefficient (Pf) is then calculated using the slope of this Vt/V0 curve. These sequential steps are time-consuming. The challenge of this work is to present a new software Phyton-based tool which allows us to process images, extract the information, calculate Vt/V0 curves, and Pf of each oocyte. We developed this new script to produce an automatic, faster, and operator-independent analysis of Pf, and compared the results with the manual/traditional approach.