Frost & Sullivan Recognizes Cisbio Bioassays for Technology ...(ying fluorescence technologies. ...)

"The determination of ligand binding affinity has been used to delineate the ligand binding site of GPCRs through a site-directed mutagenesis strategy," says Frost & Sullivan's Dr. Sudeep Basu. "These studies also provide clues to the activation mechanism of the receptors."

It is in this context that Cisbio Bioassays' Tag-lite(TM) technology is innovative and unique. It has aided the determination of ligand binding affinities without the use of radioactivity and with comparable results, making it a much safer and cost-effective process. It has also considerably reduced the time required for the ligand binding assay to nearly 1/8th the time usually needed to run a standard radio labeled ligand binding assay. Moreover, it eliminates the steps for membrane preparation or overnight counting for ligand binding.

"Further, with the development of its second generation HTRF technology, HTRF Terbium, Cisbio Bioassays has been able to improve assay performance over its previous generation HTRF, which was based on a Europium cryptate," notes Dr. Basu. "With the novel Tag-lite(TM) technology based on HTRF Terbium, Cisbio Bioassays has made possible the characterization of the GPCR from the ligand binding, signaling, and dimerization angles without compromising the functional integrity of the receptor or downstream signaling."

An important aspect of Tag-lite(TM) technology is a SNAP or CLIP tag, which is essentially a suicide enzyme with a capability of one successful reaction during which it covalently links to its substrate. These substrates can be derivatized with HTRF fluorophores. A plasmid construct can be easily generated where the SNAP or CLIP tag is attached to the N-terminus of the GPCR. Thus, a fusion protein comprised of the SNAP/CLIP tagged GPCR is expressed on the cell surface.

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