DNA recognition sequence of PAS heterodimers.

1 The names of the recognition sites are indicated: CNS midline enhancer (CME), hypoxia response element (HRE), xenobiotic response element (XRE) and the E box is the recognition site for bHLH proteins. Similar (Sima) is the fly hypoxia inducible factor-α, Spineless (Ss) functions in bristle, leg and antennal development and Period (Per), Timeless (Tim), Clock and Bmal function in circadian rhythms. 2 The CGTG core sequences shared by each recognition site are italicized. 3 The GCGTG and ACGTG sites are likely low affinity sites for Dys/Tgo [58].