title: Oxidative stress effect on progesterone-induced blocking factor (PIBF) binding to PIBF-receptor in lymphocytes.
abstract: Receptor-ligand binding is an essential interaction for biological function. Oxidative stress can modify receptors and/or membrane lipid dynamics, thus altering cell physiological functions. The aim of this study is to analyze how oxidative stress may alter receptor-ligand binding and lipid domain distribution in the case of progesterone-induced blocking factor/progesterone-induced blocking factor-receptor. For membrane fluidity regionalization analysis of MEC-1 lymphocytes, two-photon microscopy was used in individual living cells. Lymphocytes were also double stained with AlexaFluor647/progesterone-induced blocking factor and Laurdan to evaluate -induced blocking factor/progesterone-induced blocking factor-receptor distribution in the different membrane domains, under oxidative stress. A new procedure has been developed which quantitatively analyzes the regionalization of a membrane receptor among the lipid domains of different fluidity in the plasma membrane. We have been able to establish a new tool which detects and evaluates lipid raft clustering from two-photon microscopy images of individual living cells. We show that binding of progesterone-induced blocking factor to progesterone-induced blocking factor-receptor causes a rigidification of plasma membrane which is related to an increase of lipid raft clustering. However, this clustering is inhibited under oxidative stress conditions. In conclusion, oxidative stress decreases membrane fluidity, impairs receptor-ligand binding and reduces lipid raft clustering.
authors: Unitat de Biofísica, Departament de Bioquímica i de Biologia Molecular, Centre d'Estudis en Biofísica (CEB), Facultat de Medicina, Universitat Autònoma de Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain; Unitat d'Immunologia, Institut de Biotecnologia i de Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain.
authors: Carlos
authors: C
authors: de la Haba
authors: José R
authors: JR
authors: Palacio
authors: Tamas
authors: T
authors: Palkovics
authors: Júlia
authors: J
authors: Szekeres-Barthó
authors: Antoni
authors: A
authors: Morros
authors: Paz
authors: P
authors: Martínez
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000737:chemistry; D001402:B-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002232:Carbocyanines / Q000737:chemistry; D045744:Cell Line, Tumor; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007848:Laurates / Q000737:chemistry; D008560:Membrane Fluidity / Q000187:drug effects; D021962:Membrane Microdomains / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D018384:Oxidative Stress; D011257:Pregnancy Proteins / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D018121:Receptors, Cytokine / Q000737:chemistry* / Q000378:metabolism; D059010:Single-Cell Analysis / Q000379:methods*; D013194:Staining and Labeling / Q000379:methods; D013491:Suppressor Factors, Immunologic / Q000737:chemistry* / Q000378:metabolism
chemical_list: C569686:Alexa Fluor 647; D002232:Carbocyanines; D005456:Fluorescent Dyes; D007848:Laurates; C110058:PIBF1 protein, human; D011257:Pregnancy Proteins; D018121:Receptors, Cytokine; D013491:Suppressor Factors, Immunologic; D006861:Hydrogen Peroxide; D015081:2-Naphthylamine; C065580:laurdan
keywords: DMSO; FBS; GP; I(d); I(o); L(β); Laurdan; Lipid raft; Lymphocyte; Membrane fluidity; Oxidative stress; PIBF; PIBF-R; PMA; Progesterone-Induced Blocking Factor; ROS; dimethylsulphoxide; fetal bovine serum; gel phase; generalized polarization; liquid disordered; liquid ordered; phorbol-12-myristate-13-acetate; reactive oxygen species.