A novel tool for exocytosis detection based on PTrackII

Exocytosis is an important process of membrane traffic and functions such as secretion of proteins, turnover of plasma membrane and presenting receptors to plasmas membrane. However, there are few tools to observe the dynamic of vesicles and detect exocytosis automatically. PTrackII was developed to track the secretory granules with different size and motility. According to the dynamics of all tracked vesicles, exocytosis can also be recorded by PTrackII. But it is still time consuming to manually identify exocytotic events from the great amount of tracking results generated by PTrackII. This paper introduces a novel tool of ImageJ plugin based on PTrackII to automatically detect exocytosis, and this plugin can run on different platform and operating system with very high execution speed. The system can detect exocytotic events based on the differences of intensity, and list only exocytosis details instead of lots of unnecessary information. It can also trace the suddenly appeared exocytosis process. Moreover, this plugin can be used on images with different kinds of qualities and tracked objects with various dynamic morphological properties, by setting of suitable parameters. This paper illustrates a time-saving and flexible tool to help the researchers save time in exocytosis only.