ROR isoform

FIGURE 11.2 Comparison of the homology among three ROR isoforms. Percentages indicate amino acid identities in the DNA binding domain (DBD) and ligand binding domain (LBD) compared to RORa. The positions of amino acids are also labeled. 

Among other ROR isoforms, ROR [3 is believed to be involved in the processing of sensory information, as ROR(3 / mice showed significant phenotypes in circadian... 

These discoveries were followed by the isolation of cDNA for two opioid receptors derived from rat brain, identified as ROR-A and ROR-B [55], Competition studies performed with DSLET, DPDPE, and DAMGO in transfected CHO cells determined that the ROR-A corresponds to the 6-opioid receptor and ROR-B corresponds to the p-opioid receptor [55]. Finally, human cDNA for the 6-opioid was expressed in COS-7 cells [56]. Again, competition studies confirmed the presence of the 6-opioid receptor. Moreover, it was determined that the cloned receptor represents the 62-opioid receptor, since NTB showed an approximately eightfold greater affinity than BNTX [56]. The molecular biology of the cloned opioid receptors has since been reviewed [57]. It has been subsequently determined that the cloned 6-opioid receptor may correspond to the 62-isoform [57]. 

Giguere, V., Tini, M., Flock, G., Ong, E., Evans, R. M., and Otulakowski, G. (1994) Isoform-specific amino-terminal domains dictate DNA-binding properties of ROR alpha, a novel family of orphan hormone nuclear receptors. Genes Dev. 8, 538-553. 

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