Ligand-binding cavities, domain

Members of the different SERM families bind to the ligand-binding domain (LBD) of the ER, whose particular crystal structure has been revealed for estradiol and for raloxifene (Brzozowski et al. 1997). Once inserted into the binding cavity, estradiol makes direct hydrogen bonds bewteen its A-ring and... 

Renaud, J.P., Harris, J.M., Downes, M., Burke, L.J. and Muscat, G.E. (2000) Structure-function analysis of the Rev-erbA and RVR ligand-binding domains reveals a large hydrophobic surface that mediates corepressor binding and a ligand cavity occupied by side chains. Molecular Endocrinology, 14, 700—717. 

Heptahelical domains are protein modules found in all known G-protein coupled receptors, made up of seven transmembrane helices interconnected by three extra and three intracellular loops. For most G-protein coupled receptors activated by small ligands, the binding site is located in a cavity formed by transmembrane domains 3, 5, 6 and 7. 

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