Fig. 9. Model of the mouse leptin/CRH2 complex. The molecular surface of leptin is coloured according to the surface hydrophobicity (blue, hydrophilic; green, hydrophobic). The CRH2 model is presented as ribbons, the C
atom and heavy side chain atoms of residues I501, F502, L503, L504S and D615 are displayed as white sticks. L504 of CRH2 fits into the hydrophobic cleft of leptin and interacts with L13 and L86 of leptin.