该基因产物属于核受体超家族，其成员是以配体结合域和DNA结合域为特征的转录因子编码蛋白是细胞色素P450基因CYP3A4的转录调节因子，与CYP3A4启动子的反应元件以异二聚体形式与9顺式维甲酸受体RXR结合它被一系列诱导cyp3a4的化合物激活，包括地塞米松和利福平。已经描述了几种编码不同亚型的选择性剪接转录本，其中一些使用非aug（cug）翻译起始密码子。额外的转录变体存在，但是，它们还没有被完全表征。[由RefSeq提供，2008年7月]
This gene product belongs to the nuclear receptor superfamily, members of which are transcription factors characterized by a ligand-binding domain and a DNA-binding domain. The encoded protein is a transcriptional regulator of the cytochrome P450 gene CYP3A4, binding to the response element of the CYP3A4 promoter as a heterodimer with the 9-cis retinoic acid receptor RXR. It is activated by a range of compounds that induce CYP3A4, including dexamethasone and rifampicin. Several alternatively spliced transcripts encoding different isoforms, some of which use non-AUG (CUG) translation initiation codon, have been described for this gene. Additional transcript variants exist, however, they have not been fully characterized. [provided by RefSeq, Jul 2008]