Now that Promega is expanding its offerings of options for examining live-cell protein interactions or quantitation at endogenous protein expression levels, we in Technical Services are getting the question about which option is better. The answer is, as with many assays… it depends! First let’s talk about what are the NanoBiT and NanoBRET technologies, and then we will provide some similarities and differences to help you choose the assay that best suits your individual needs. Continue reading “A BiT or BRET, Which is Better?”
It’s always nice to know that someone is reading your paper. It’s a sign that your research is interesting, useful and actually has an impact on the scientific community. We were thrilled to learn that papers published by Promega scientists made the top 10 most read papers of 2017 in the journal ACS Chemical Biology. In fact, Promega scientists authored five of the top six most read papers! Let’s take a look at what they are.
Publication Date (Web): September 11, 2017
This 2017 paper introduces our newest star: HiBiT, a tiny 11aa protein tag. To any scientist studying endogenous protein expression, the HiBiT Tagging System is your dream come true. It combines quantitative and highly sensitive luminescence-based measurement with a tiny-sized tag that can be easily inserted into endogenous protein via CRISPR/Cas9 gene editing with little impact on native protein function. The HiBiT Tagging System has been listed as a 2017 Top 10 Innovation by The Scientist, and it will drastically change how we study endogenous protein expression. Continue reading “Top 5 Most Read Promega Papers in 2017”
Cannabinoids. What are they? Sometimes, Wikipedia can give a nice definition:
A cannabinoid is one of a class of diverse chemical compounds that acts on cannabinoid receptors in cells that alter neurotransmitter release in the brain. Ligands for these receptor proteins include the endocannabinoids (produced naturally in the body by animals), the phytocannabinoids (found in Cannabis and some other plants), and synthetic cannabinoids (manufactured artificially).
Synthetic cannabinoids (SCs) were originally created for the scientific investigation of two cannabinoid receptors, CB1 and CB2, but have made their way to the streets as “safe” and “legal” alternatives to marijuana.
The problem is that these SCs engage the cannabinoid receptors more completely and with higher affinity than anything derived from marijuana. As a result, SCs can produce serious side effects that often require medical attention. In fact, you are 30 times more likely to seek emergency medical attention following the use of an SC than with natural cannabinoid sources like marijuana. Continue reading “Bioassay for Cannabinoid Receptor Agonists Designed with NanoBiT™ Techology”
Most, if not all, processes within a cell involve protein-protein interactions, and researchers are always looking for better tools to investigate and monitor these interactions. One such tool is the protein complementation assay (PCA). PCAs use a reporter, like a luciferase or fluorescent protein, separated into two parts (A and B) that form an active reporter (AB) when brought together. Each part of the split reporter is attached to one of a pair of proteins (X and Y) forming X-A and Y-B. If X and Y interact, A and B are brought together to form the active enzyme (AB), creating a luminescent or fluorescent signal that can be measured. The readout from the PCA assay can help identify conditions or factors that drive the interaction together or apart.
A key consideration when splitting a reporter is to find a site that will allow the two parts to reform into an active enzyme, but not be so strongly attracted to each other that they self-associate and cause a signal, even in the absence of interaction between the primary proteins X and Y. This blog will briefly describe how NanoLuc® Luciferase was separated into large and small fragments (LgBiT and SmBiT) that were individually optimized to create the NanoBiT® Assay and show how the design assists in monitoring protein-protein interactions.
It’s a new year. Whether you’re a self-improvement fanatic or just ready for good things to start happening, you’ve got a plan. You might be changing up an old exercise routine or trying a new cooking technique.
And at work, you are digging deeper; this is the year you illuminate the protein interactions that you’ve previously not been able to visualize.
Good news. There is a new protein complementation assay that can help.
NanoBiT™ Complementation Reporter is a recently developed protein interaction assay that features the improved NanoLuc® luciferase. NanoLuc, originally isolated from a deep sea shrimp, is a small luciferase that provides a much brighter signal than firefly luciferase.
About Split Luciferase Systems
If you’re interrogating two proteins to understand the conditions under which they interact, a split luciferase system enables you to tag each protein with a luciferase subunit. Interaction of the tagged proteins facilitates the complementation of the subunits, resulting in a luminescent signal. Continue reading “Studying Mitochondrial Fission with NanoBiT Complementation Assay”
Our understanding of the microscopic world has been shaped by the tools available to monitor and visualize cellular interactions. We “stand on the shoulders of giants” to propel our research to even greater heights. Studying protein-protein interactions (PPI) has proved fruitful for our understanding of cellular metabolism, signal transduction, and more. Scientists are starting to build whole organism interactomes (kindred to the metabolome and genome) that could have huge implications towards understanding and treating disease. Let us take a trip down memory lane to see where we have come from. Continue reading “Key Advances in PPI Research”
For three out of the last four years, we have been honored to have one of our key technologies named a Top 10 Innovation by The Scientist. This year the innovative NanoBiT™ Assay (NanoLuc® Binary Technology) received the recognition. NanoBiT™ is a structural complementation reporter based on NanoLuc® Luciferase, a small, bright luciferase derived from the deep sea shrimp Oplophorus gracilirostris.
Using plasmids that encode the NanoBiT complementation reporter, you can make fusion proteins to “report” on protein interactions that you are studying. One of the target proteins is fused to the 18kDa subunit; the other to the 11 amino acid subunit. The NanoBiT™ subunits are stable, exhibiting low self-affinity, but produce an ultra-bright signal upon association. So, if your target proteins interact, the two subunits are brought close enough to each other to associate and produce a luminescent signal. The strong signal and low background associated with a luminescent system, and the small size of the complementation reporter, all help the NanoBiT™ assay overcome the limitations associated with traditional methods for studying protein interactions.
The small size reduces the chances of steric interference with protein interactions. The ultra bright signal, means that even interactions among proteins present in very low amounts can be detected and quantified–without over-expressing large quantities of non-native fusion proteins and potentially disrupting the normal cellular environment. And the NanoBiT™ assay can be performed in real time, in live cells.
The NanoBiT™ assay is already being deployed in laboratories to help advance understanding of fundamental cell biology. You can see how one researcher is already taking full advantage of this innovative technology in the video embedded below:
Visit the Promega web site to see more examples more examples how the NanoBiT™ assay can break through the traditional limitations for studying protein interactions in cells.
You can read the Top 10 article in The Scientist here.