Photo-activation, -conversion, & -switching
Advances in fluorescent protein technology have made photoactivation techniques broadly available in the cell biology lab. By using these techniques, researchers can fluorescently highlight/label specific protein populations in the cell such that their movement and behavior can be tracked over time. Also, photoactivation methods can be applied at different scales, allowing researchers to track proteins within cells, or alternatively to track cells within tissues.
Photoactivatable fluorescent proteins can be activated from a dark (i.e., non-fluorescent) state to a fluorescent state under a specific wavelength of light. The commonly used photoactivatable GFP (PA-GFP) protein, for example, undergo dark to fluorescent state transition under activation with 405nm light. By fusing photoactivatable fluorescent proteins to other proteins of interest, researchers can monitor movement rate and direction. .
Photoconvertible fluorescent proteins irreversibly transition from one absorption/emission spectra state to another absorption/emission spectra state when activated with a specific wavelength of light. Green-to-red photoconvertible proteins are the most common and include Kaede, Dendra2, and Eos among others. Photoconversion provides an advantage to photoactivation in that it allows researchers to monitor the movement of two fractions of the same protein population simultaneously over time.
Photoswitchable fluorescent proteins reversibly transition between dark and fluorescent states under different wavelengths of light. The most commonly used photoswitchable protein is Dronpa, which transitions into a green fluorescent state under 405nm light and is inactivated into its dark state under 488nm light. Photoswitching allows cell biologists to repeatedly monitor labelled proteins in multiple subcellular regions of the cell.
This configuration based on Mightex’s Polygon400 provides:
1) High-intensity photoactivation on sample of any shape, size or number of regions of interest.
2) High-intensity lasers used with Mightex’s Polygon400 DL.
3) Synchronization with imaging equipment and camera.
4) Integrates into any commercial microscope (upright or inverted).