Dronpa

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Dronpa is a photoactivatable fluorescent protein derived from a species of coral in the genus Pectiniidae. It is widely used in cell biology and molecular biology for its ability to switch between a fluorescent and non-fluorescent state upon exposure to specific wavelengths of light.

Discovery and Origin

Dronpa was first discovered in a species of coral from the genus Pectiniidae. The protein was named "Dronpa" as a portmanteau of "Dron" (a Japanese word for "turn on") and "pa" (for photoactivation).

Structure and Properties

Dronpa belongs to the family of GFP-like proteins and shares a similar beta-barrel structure. It exhibits a unique ability to switch between a bright fluorescent state and a dark state when exposed to light of specific wavelengths. This property is known as photochromism.

Photoactivation

Dronpa can be switched on (activated) by exposure to cyan light (around 488 nm) and switched off (deactivated) by exposure to ultraviolet light (around 405 nm). This reversible switching makes it a valuable tool for super-resolution microscopy and other advanced imaging techniques.

Applications

Dronpa is used extensively in live-cell imaging due to its reversible photoactivation properties. It allows researchers to track the movement and interaction of proteins within living cells with high spatial and temporal resolution. Some of the key applications include:

• Fluorescence resonance energy transfer (FRET)
• Photoactivated localization microscopy (PALM)
• Fluorescence recovery after photobleaching (FRAP)

Advantages

The main advantages of Dronpa over other fluorescent proteins include its high brightness, photostability, and the ability to be repeatedly switched on and off. These properties make it particularly useful for long-term imaging studies.

Limitations

Despite its many advantages, Dronpa has some limitations. The requirement for specific wavelengths of light for activation and deactivation can limit its use in certain experimental setups. Additionally, the potential for phototoxicity due to prolonged exposure to activating light is a concern in live-cell imaging.

Variants

Several variants of Dronpa have been developed to improve its properties or to provide different colors of fluorescence. These include:

• Dronpa-2
• mEos2
• mMaple

See Also

• Green fluorescent protein
• Photoactivatable fluorescent proteins
• Super-resolution microscopy
• Live-cell imaging