Figure 1.

(A) Ribbon diagram of the ternary complex of human growth hormone (hGH) bound to two copies of the extracellular domain (ECD) of the human growth hormone receptor (hGHR; de Vos et al. 1992). The hGHR ECD1 and ECD2 are colored red and blue, respectively. The Site2 binding interface between hGH and the hGHR ECD2 is circled. (B) Accessible surface area burial of Site2 interface residues of hGH (top bars) and hGHR ECD2 (bottom bars). All structural figures were generated by using the program Pymol (Warren DeLano, www.pymol.org).