Prof Ago Rinken (MD, PhD), University of Tartu
Sergei Kopantšuk (PhD), University of Tartu
Opponent: Dr. Stephen John Briddon, Principal Research Fellow, University of Nottingham, UK
Current PhD thesis "Development of assay systems for characterisation of ligand binding properties to melanocortin 4 receptors" describes our progress of melanocortin receptor studies connected with development of novel assay systems that would facilitate the discovery of novel receptor specific ligands. Melanocortin receptors are involved in regulation of wide variety of physiological functions like pigmentation, sexual behaviour, regulation of energy balance and feeding behaviours, temperature control and pain sense, inflammatory and immune responses and others. Thus, ligands for these receptors have a remarkable therapeutic potential for treatment of several human disorders like obesity and anorexia, melanoma, erectile dysfunction and sexual motivation, as well as anxiety and depression. Success in discovery of new drugs, in many aspects depends from our ability to understand the mechanisms of receptor-ligand interactions and use this to design novel, receptor subtype selective, potent and metabolically suitable drugs. Besides that, assay properties may play a very important role in interpretation of results, as the ability to see the effect of the drug depends on the "eyes" of the assay through which it is monitored. Fluorescence anisotropy-based assay systems we developed avoid the use of radioactive ligands and allow on-line monitoring of receptor-ligand interactions that would improve general understanding of the melanocortin system.