• Visualize very fast actin dynamics in live cells: fluorogenic, orange probe, optimized for measuring very fast actin dynamics
• Visualize stable actin filaments in live cells
• Supports multi-color imaging

SPY™555-FastAct™_X probe is based on the SPY™ dye conjugated to a chemically modified version of the actin binding natural product jasplakinolide. This creates a probe that can label very fast actin dynamics but lacks the undesired F-actin stabilization effects of the parent compound. Its mildly fluorogenic nature allows the labelling of F-actin in live cells with high specificity and low background.

Key features

• Ab: 564 nm, Em: 589 nm – orange spectrum
• Cell-permeable
• Works on live cells
• Enables exceptional insight into live cell actin dynamics
• Mildly fluorogenic character: enhanced fluorescence when bound to F-actin
• Compatible with confocal, STED, light sheet, and spinning disk imaging. As SPY™555-FastAct™_X is only mildly fluorogenic, it should be imaged by microscopes that are capable of out-of-focus light exclusion. Widefield microscopy is not recommended for imaging with this reagent due to a high background.

The biological activity of SPY™555-FastAct™_X probe is assessed by the ability of the probe to efficiently label actin filaments and very rapid actin dynamics in live HeLa cell culture. Wash steps are not recommended for visualization of fast actin dynamics.