Bioassay for Cannabinoid Receptor Agonists Designed with NanoBiT™ Techology

Cannabinoids. What are they? Sometimes, Wikipedia can give a nice definition:

Tetrahydrocannabinol (THC), a partial agonist of the CB1 and CB2 cannabinoid receptors. Wikipedia Commons

Tetrahydrocannabinol (THC), a partial agonist of the CB1 and CB2 cannabinoid receptors. Wikipedia Commons

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

GPCR Targets are a Dimer a Dozen

G protein-coupled receptors (GPCRs) are the most prevalent gene family in the human genome. They are involved with everything from our sense of smell to immune system function to tumor growth. Unsurprisingly, GPCRs have been a hotbed for research and development. Of the 7,038 approved drugs analyzed for this blog post, I found that 29% of them target Class A (Rhodopsin-like) GPCRs, and 35% target any GPCR. In the spirit of Internet pop culture, I made a “quiz” to see if you can guess the top 10 receptors by their ligand’s chemical structure.

GPCR-Top10-graph

Can you guess these GPCR receptors by their ligand chemical structures?

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Practical Tips for HEK293 Cell Culture When Using cAMP-Glo™ Assay

HEK293 cells stably expressing HaloTag®-ECS (ExtraCellular Surface; comprised of a signal sequence and single transmembrane domain of β1-integrin) fusion protein labeled with HaloTag® Alexa Fluor® 488 Ligand and then imaged.

HEK293 cells stably expressing HaloTag®-ECS (ExtraCellular Surface; comprised of a
signal sequence and single transmembrane domain of β1-integrin) fusion protein labeled
with HaloTag® Alexa Fluor® 488 Ligand and then imaged.

G Protein Coupled Receptors represent one of the largest classes of cell surface receptors and one of the most important classes for drug targets. Fifty of the top 200 drugs target GPCRs. GPCRs respond to various stimuli like light, odors, hormones, neurotransmitters and others. They cover virtually all therapeutic areas. When a particular GPCR is implicated in a disease, researchers screen the GPCR and its signaling pathways, the hope being that promising therapeutic targets might be identified. Major G-protein families signal via secondary messengers like cAMP, which in turn activate a range of effector systems to change cell behavior and/or gene transcription. There are various approaches and methods to study GPCRs and measure the increase or decrease of intracellular cAMP. However, the fastest and the most sensitive among all methods is a plate based cAMP-Glo™ Assay. Continue reading