Sub-cell FRET imaging for determination of signaling pathway of cell apoptosis during tumor therapy

摘要

The current advances in fluorescence microscopy, coupled with the development of new fluorescent probes, make fluorescence resonance energy transfer (FRET) a powerful technique for studying molecular interactions inside living cells with improved spatial and temporal resolution, distance range, and sensitivity and a broader range of biological applications. In recent years, a large number of studies have been conducted aiming to understand the process of apoptosis during tumor therapy on a molecular basis. Here, we utilized a recombinant FRET Bid probe to determine the kinetics of Bid cleavage during Cisplatin-induced apoptosis in ASTC-a-1 cells. Cells treated with Cisplatin (20 μM) showed a cleavage of the Bid-FRET probe, occurring at about 4-5 h after onset of the Cisplatin exposure, and lasted about 1.5 h. Our data clearly showed the kinetics of Bid cleavage during Cisplatin-induced apoptosis. We also used FRET technique to measure the dynamics of caspase-3 activation during apoptosis induced by high fluence low-power laser irradiation (LPLI). The data showed that we can detect caspase-3 activation sensitively and effectively, by using the FRET probe SCAT3.