Building up on the work performed in the lab of Gobind Khorana , the team of Karl Deisseroth engineered chimeric receptors by replacing the intracellular loops of the bovine rhodopsin with those of specific adrenergic receptors , taking advantage of common structure-function relationships amongst GPCRs. Using these tools they were able to optically activate the intracellular pathways normally recruited by these receptors (the cAMP and IP3 pathways). Following a similar approach, the team of Stefan Herlitze produced a light-activated receptor which recruits the signaling cascade of a specific serotonin receptor . These emerging tools might be gathered under the name “opto-XRs” proposed by Airan et al. , where X specifies the particular pathways which is being optically "hijacked" (e.g. opto-α1AR for α1 adrenergic receptors).
bleach-resistant opsin from the box jellyfishCarybdea rastonii. The light dependent increase in cAMP induced by JellyOp is both higher amplitude and more repeatable than the response driven by currently available OptoXRs.