20.500.12556/RUL-124840 Electron paramagnetic resonance gives evidence for the presence of type 1 gonadotropin-releasing hormone receptor (GnRH-R) in subdomains of lipid rafts This study investigated the effect of type 1 gonadotropin releasing hormone receptor (GnRH-R) localization within lipid rafts on the properties of plasma membrane (PM) nanodomain structure. Confocal microscopy revealed colocalization of PM-localized GnRH-R with GM$_1$-enriched raft-like PM subdomains. Electron paramagnetic resonance spectroscopy (EPR) of a membrane-partitioned spin probe was then used to study PM fluidity of immortalized pituitary gonadotrope cell line αT3-1 and HEK-293 cells stably expressing GnRH-R and compared it with their corresponding controls (αT4 and HEK-293 cells). Computer-assisted interpretation of EPR spectra revealed three modes of spin probe movement reflecting the properties of three types of PM nanodomains. Domains with an intermediate order parameter (domain 2) were the most affected by the presence of the GnRH-Rs, which increased PM ordering (order parameter (S)) and rotational mobility of PM lipids (decreased rotational correlation time (τc)). Depletion of cholesterol by methyl-β-cyclodextrin (methyl-β-CD) inhibited agonist-induced GnRH-R internalization and intracellular Ca$^{2+}$ activity and resulted in an overall reduction in PM order; an observation further supported by molecular dynamics (MD) simulations of model membrane systems. This study provides evidence that GnRH-R PM localization may be related to a subdomain of lipid rafts that has lower PM ordering, suggesting lateral heterogeneity within lipid raft domains. 7TM receptors type 1 gonadotropin-releasing hormone receptor plasma membrane electron paramagnetic resonance (EPR) lipid rafts receptors LHRH cell membrane electron spin resonance spectroscopy true false true Angleški jezik Ni določen Članek v reviji 2021-02-23 09:48:42 2021-02-23 09:48:42 2022-09-04 04:01:48 0000-00-00 00:00:00 2021 0 0 17 str. iss. 4, art. 973 Vol. 26 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 576 1420-3049 10.3390/molecules26040973 51410947 18462981 RAZ_Koklic_Tilen_2021.pdf RAZ_Koklic_Tilen_2021.pdf 1 A78A5D3E9436D4B3300C8315F454D8AE 80617f8cff62fc5b60af24b53553bff5a9dc26dccb3c6322d2231dd77c793b04 0a69a60f-9309-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=153935 https://www.mdpi.com/1420-3049/26/4/973 0 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=140462 Veterinarska fakulteta Medicinska fakulteta 0 0 0