The main project objective is to investigate allosteric binding sites for zinc ions at 5-HT7 and 5-HT2A serotonin receptors, to determine whether allosteric regulation of these ions reported at 5-HT1AR is subtype selective, or it can also be detected at other representatives of serotonergic receptor family. It was shown that zinc ions are natural allosteric modulator for several different groups of G-protein coupled receptors (GPCR), such as dopamine D1 and D2, alpha1 and beta2-aderenergic, which suggests a more universal character of this mode of zinc ions interaction.
Binding of allosteric modulator promotes changes in receptor conformation, which influences the affinity of the endogenous (or other orthosteric) ligand and the formation of ligand-receptor complex. In order to study the mechanism of this interaction, changes in affinity and dissociation rate of orthosteric ligands, radioligand binding methods were selected. HEK293 cell lines stably transfected with cDNA vectors encoding the human serotonin 5-HT1A, 5-HT2A, 5-HT7b (obtained at the Department of Medicinal Chemistry (ZChL), and routinely maintained) and the following radioligands: [3H]8-OH DPAT (for 5-HT1AR), [3H]ketanserin (for 5-HT2AR) and [3H] 5-CT and [3H]SB 269970 (for 5-HT7R), will be used. In general, the above methods are consistent to the procedures developed at ZChL to study ortosteric ligands interactions, and the only differences relate to simultaneous incubation of zinc with different compounds, and measurements of several, different time points. To the analysis of allosteric reaction results, so-called “allosteric tertnary complex model” will be adopted.
Expected impact of the project on the development of science, civilization and society
Both serotonin receptors and zinc ions play important functions in the central nervous system (CNS) but many aspects of their action remains unclear. The result of the project will be characterization of zinc ion interactions with two serotonin receptors: 5-HT7 and 5-HT2A, which will add new contribution to the existing knowledge on the mechanisms of zinc action in the CNS, and the possibility of allosteric modulation of 5-HT7 and 5-HT1A receptors. In recent years, various aspects of GPCR allosterism were intensively studied, because the interaction with the receptor according to other than classical, competitive model of orthosteric ligand binding, creates new possibilities for its regulation. It is even believed, that in a longer research term, it could be an area for the search of the next generation of drugs acting on the CNS. As a bacgroung, however, results of a basic research, identifying the allosteric binding site for a given receptor, and confirming their positive impact on the potential therapeutic effects, are necessary. In this context, the results of this research project, are form of “prelude” for new direction of searching allosteric modulators of serotonin GPCR, which determines their contribution to the development of medicinal chemistry. Given the negligible (~ 5) number of reports describing examples of allosteric modulation of serotonin receptors, the planned research may be regarded pioneering.
Grzegorz Satała, MSc
phone: +4812 66 23 301
- Grzegorz Satała, Tomasz Lenda, Beata Duszyńska, Andrzej J. Bojarski Mechanizm oddziaływania jonów cynku z wybranymi typami receptora serotoninowego. Dokonania Naukowe Doktorantów III Edycja. 18.04.2015, Kraków Abstrakt
- Grzegorz Satała, Tomasz Lenda, Beata Duszyńska, Andrzej J. Bojarski Identyfikacja modulacji allosterycznej w grupie receptorów serotoninowych GPCR. Wpływ Młodych Naukowców na Osiągniecia Polskiej Nauki VIII Edycja. 28.03.2015, Poznań Abstrakt Wykład
- Grzegorz Satała; Stefan Mordalski; Beata Duszyńska; Andrzej J. Bojarski: Badanie wpływu jonów cynku na receptory serotoninowe 5-HT7 metodami in vitro i in silico. II Ogólnopolskie Sympozjum Interdyscyplinarne Inter-Mix 2014, 20-23.11.2014, Dolny Śląsk Abstrakt Poster
- Grzegorz Satała; Beata Duszyńska; Andrzej J. Bojarski: Pharmacological characterization of zinc interaction with 5-HT7; VI Konwersatorium Chemii Medycznej, 18-20.09.2014, Lublin Abstrakt Poster
The study is supported by a grant PRELUDIUM DEC-2012/05/N/NZ7/02110 financed by the National Science Centre