A putative step in steroid hormone action involves insertion of steroid ligands into DNA facilitated by receptor proteins.

摘要: Abstract The hypothesis is advanced that hormonal ligands in the steroid/thyroid superfamily act through insertion between base pairs partially unwound DNA. Using published X-ray coordinates of complex glucocorticoid hormone response element (GRE) with receptor DNA binding domain, interface protein and gene was examined. site 5′-TG-3′-5′-CA-3′ previously shown to accommodate cortisol found first two bases GRE half sites, 5′-TGTTCT-3′. These were sufficiently exposed at receptor-gene permit access by steroid. Docking into receptor/DNA resulted a favorable van der Waals energy. Given general lack correlation activity, we propose action involves an additional step which concert other transcription factors inserts This notion provides explanation for earlier paradoxical observations including structural analogies steroid hormones. suggests bound ligand facilitates unwinding, stereospecific control donor/acceptor functional groups on followed release 5′-TG-3′-5′-CA-3′.