Of this group of enzymes, the luciferase from Renilla reniformis has been the most extensively studied, and due to its bioluminescence requiring only molecular oxygen, has a wide range of applications, with uses as a reporter gene probe in cell culture, in vivo imaging, and various other areas of biological research.

[2] Recently, chimeras of RLuc have been developed and demonstrated to be the brightest luminescent proteins to date, and have proved effective in both noninvasive single-cell and whole body imaging.

coelenteramide + CO2 + hν In the process, coelenterazine is oxidized with a concurrent loss of CO2, and a photon of blue light is emitted.

[5] In Renilla reniformis, RLuc is found in membrane-bound intracellular structures within specialized light emitting cells,[6][7] and is coupled with a closely interacting green fluorescent protein (RrGFP),[8] and a Ca++ activated luciferin binding protein (RrLBP).

[9] Although the luciferase catalyzed oxidation of coelenterazine releases a photon of blue light (480 nm), this is not observed in vivo.

This process relies on a Förster resonance energy transfer (FRET) mechanism, increasing the emitted photon number approximately six-fold.

[11] Renilla luciferase contains 311 amino acids,[1] and is active as a nearly spherical single polypeptide chain monomer of 36 kDa, which have a tendency for self-association, forming inactive dimers and trimers.

[12][13] Like other dehalogenase-superfamily enzymes, it has a characteristic α/β-hydrolase fold sequence at its core[14] and shares the conserved catalytic triad of residues employed by dehalogenases.

[9] Coelenterazine is then oxidized by RLuc into coelenteramide, releasing a single photon of blue light (480 nm) in the process.

The RLuc mediated chemical reaction involves the catalytic degradation of coelenterazine, and proceeds through a 1,2-dioxetane (also called dioxetanone or cyclic peroxide) intermediate.