The trap-like relaxin-binding site of the leucine-rich G-protein-coupled receptor 7.

摘要: The pleated sheet region of the leucine-rich G-protein-coupled receptor 7 supports a relaxin-binding group amino acids that perfectly matches binding cassette relaxin. Arginines B13 and B17 are each chelated by an aspartic acid/glutamic acid pair isoleucine B20, which, offset one-quarter helix turn from straight line connecting arginines, interacts with cluster hydrophobic acids. relaxin cuts at angle ∼45° across five parallel repeats. arginine residues 13 17, which evolve B-chain α-helix relaxin, neutralize charge repulsion juxta-posed acidic groups on thereby trigger closure hydrogen bonding network around guanidinium groups. Thus, is bound synchronized chelation two arginines stabilized interaction B20 tryptophan, isoleucine, leucine in neighboring repeats receptor. Deletion any one three features diminishes to level nonspecific binding. This model explains exquisite sensitivity avidity minute changes disposition size dependence residue position B20.