Time-Resolved Förster Resonance Energy Transfer-Based Technologies to Investigate G Protein-Coupled Receptor Machinery: High-Throughput Screening Assays and Future Development - Progress in Molecular Biology and Translational Science - page 307

to the immobilized estrogen receptor in homogeneous format by FRET
measurement on a microarray (for review, see Ref. 84 ). Altogether, this
opens up new perspectives to develop TR-FRET-based microarrays to an-
alyze GPCR properties.

6. CONCLUSION

As illustrated by the solutions available on GPCR, TR-FRET is cur-
rently a method of choice for HTS campaigns. Its high sensitivity makes it
compatible with the use of the 384- or 1536-well plate format. Miniaturi-
zation allows reduction of the amount of compound used and therefore the
price of the assay. In addition, most of the assays presented above do not re-
quire washing steps and thus are perfectly compatible with automation of the
screening process.
More than GPCR, TR-FRET-based assays could be used to study most
of the membrane proteins. Actually, activating a cell-surface protein results
in modifications in the intracellular components. The kinase assays, for ex-
ample, are also compatible to screen for compound on tyrosine kinases re-
ceptors. Tag-lite Ò strategy could be used on any cell-surface receptor both in
its ligand-binding format and in its oligomerization assay. Though the fluo-
rescent techniques are preferred to radioactive assays by pharmaceutical
companies, the novel TR-FRET-based assays represent a further improve-
ment and have the potential to gain more importance in the future screening
campaigns.

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