The DNA-binding domain of Ecdysone receptor (EcR) like nuclear receptor family is composed of two C4-type zinc fingers
The DNA-binding domain of Ecdysone receptor (EcR) like nuclear receptor family is composed of two C4-type zinc fingers. Each zinc finger contains a group of four Cys residues which co-ordinates a single zinc atom. EcR interacts with specific DNA sites upstream of the target gene and modulates the rate of transcriptional initiation. This family includes three types of nuclear receptors: Ecdysone receptor (EcR), Liver X receptor (LXR) and Farnesoid X receptor (FXR). The DNA binding activity is regulated by their corresponding ligands. The ligands for EcR are ecdysteroids; LXR is regulated by oxidized cholesterol derivatives or oxysterols; and bile acids control FXR's activities. Like other members of the nuclear receptor (NR) superfamily of ligand-activated transcription factors, EcR-like receptors have a central well conserved DNA binding domain (DBD), a variable N-terminal domain, a flexible hinge and a C-terminal ligand binding domain (LBD).