Promega NanoBiT Complementation Assay Named a Top 10 Innovation

NanoBiT is a clever structural complementation reporter based on NanoLuc, a novel luciferase derived from the deep sea shrimp, Oplophorus gracilirostris. Scientists can use the new NanoBiT to explore protein:protein interactions in living cells in real time, including tracking association and dissociation. 

The new tool is helping advance the understanding of fundamental cellular biology in human diseases and can be used to monitor cellular interactions in a more biologically relevant, live-cell approach. Kathryn Luker, an academic researcher, is using NanoBiT in researching the role of chemokine receptor signaling in the mechanisms of primary and metastatic cancer. "Of the many luciferase complementation methods we have used, NanoBiT offers the best combination of strong signal, low background, small size and ATP-independence," said Luker. 

"This is definitely a great new tool for developing luminescence-based assays of many kinds," added Luker. "Moreover, NanoBiT works well for imaging intracellular protein associations in live cells."

Using plasmids that encode the NanoBiT complementation reporter, researchers can easily make fusion reporters with the proteins they are interested in studying. If their proteins do interact, the two subunits of NanoBiT are brought together to reform an active enzyme producing a bioluminescent signal. Scalable, plate-based format and directly proportional activity to signal make NanoBiT ideal for high-throughput screening.

Promega R&D engineered and optimized the 18kDa and 1kDa subunits of NanoBiT to be stable, with low self-affinity and an ultra-bright signal upon association. The result is a protein interactions detection system that is reversible and exhibits low interference. Experiments, therefore, can be conducted at native expression levels, and the complementation system emits light only when the two unique subunits properly reform the complete structure.