Leptin Leptin is a hormone involved in appetite. How many cross-over connections are there? (Note: not all amino acids are shown in this model.) Zhang, F., Basinski, M. B., Beals, J. M., Briggs, S. L., Churgay, L. M., Clawson, D. K., DiMarchi, R. D., Furman, T. C., Hale, J. E., Hsiung, H. M., Schoner, B. E., Smith, D. P., Zhang, X. Y., Wery, J. P., Schevitz, R. W.: Crystal structure of the obese protein leptin-E100. Nature 387 pp. 206 (1997) (PubMed) 1ax8 (PDB)

Growth hormone How many cross-over connections are there? Is the topology of growth hormone the same as leptin? de Vos, A. M., Ultsch, M., Kossiakoff, A. A.: Human growth hormone and extracellular domain of its receptor: crystal structure of the complex. Science 255 pp. 306 (1992) (PubMed) 1hhr (PDB)