this gene encodes a member of the retinoid x receptor (rxr) family of nuclear receptors which are involved in mediating the antiproliferative effects of retinoic acid (ra). this receptor forms heterodimers with the retinoic acid, thyroid hormone, and vitamin d receptors, increasing both dna binding and transcriptional function on their respective response elements. this gene is expressed at significantly lower levels in non-small cell lung cancer cells. alternate transcriptional splice variants, encoding different isoforms, have been characterized.