Résumé
Assessing the dynamics of plasma membrane diffusion processes in live cell fluorescence microscopy is of paramount interest to understand cell mechanisms. We propose a new method to detect vesicle fusion events, and estimate the associated diffusion coefficients in image sequences of total internal reflection fluorescence microscopy (TIRFM). In contrast to usual approaches, a diffusion coefficient is locally estimated for each detected fusing vesicle. We first detect the membrane fusion events and then select the diffusion configurations among them with a correlation test. To estimate the diffusion coefficient, a geometric model is fitted to the detected spot directly in the 2D+t subvolume. Quantitative results demonstrate the accuracy of the proposed method.