The Structural Basis of Gas-Responsive Transcription by the Human Nuclear Hormone Receptor REV-ERBĪ²
Figure 3
REV-ERBs Can Assume at Least Six Different Heme Binding States
In the absence of heme, the ligand pocket of REV-ERBs is stabilized with the side chains of core hydrophobic residues. Heme can bind to the REV-ERBs in either reduced Fe(II) or oxidized Fe(III) states, and while reduced is in a five or six coordinate state. REV-ERBs also bind the diatomic gases CO and NO through the creation of a coordinate bond between the Fe(II) center of heme.