text: The ability of this cis-acting RAR-RXR binding element to activate transcription in response to << RA >> also depended on downstream sequences where an octamer transcription factor 1 (Oct1) site and a [[ nuclear factor of activated T cells ]] (NFATc) site between this element and the transcriptional start, as well as a cyclic AMP response element binding factor (CREB) site between the transcriptional start and first exon of the blr1 gene, were necessary.