Butler S.J.,Durham University |
Lamarque L.,Cisbio Bioassays |
Pal R.,Durham University |
Parker D.,Durham University
Chemical Science | Year: 2014
Nine very bright europium(iii) complexes with different macrocyclic ligands have been prepared that exhibit excellent cell uptake behaviour and distinctive sub-cellular localisation profiles, allowing the use of fluorescence microscopy and time-gated spectral imaging to track their fate in cellulo. Their use as cellular imaging stains is described for the selective illumination of mitochondria, lysosomes or the endoplasmic reticulum of various mammalian cell types. © 2014 the Partner Organisations.
Ayoub M.A.,Universites Montpellier I and |
Ayoub M.A.,University of Western Australia |
Trinquet E.,Cisbio Bioassays |
Pfleger K.D.G.,University of Western Australia |
Pin J.-P.,Universites Montpellier I and
FASEB Journal | Year: 2010
Although many G protein-coupled receptors (GPCRs) are known to activate multiple signaling pathways by coupling to different types of G proteins or by promoting G protein-independent events, how this occurs remains unclear. Using bioluminescence resonance energy transfer and time-resolved fluorescence resonance energy transfer, we provide evidence for protease-activated receptor 1 (PAR1) forming preassembled complexes with Gαi1 but not Gα12. PAR1 activation appears to rapidly induce transient Gαi1 activation (t1/2 = 4.13 s) but late and stable recruitment of Gα12 (t1/2 = 8.8 min) in parallel with β-arrestin 1 (t1/2 = 7.5 min). However, there is no significant difference in the potency of the agonist-dependent response between Gαi1, Gα12, and β-arrestin 1 (EC50 values 0.48, 0.30, and 0.15 nM, respectively). Although it seems β-arrestin 1 is recruited to preassembled PAR1-Gαi1 complexes, this appears unlikely with Gα12, suggesting 2 distinct receptor populations. Of note, we observed a different Gα12 association mode with other GPCRs, indicating that preassembly and association dynamics may be specific properties of a receptor-G protein pair. Furthermore, the Gα C terminus appears to play different roles in the distinct association modes. Consequently, G protein preassembly or recruitment may constitute novel mechanisms for controlling the kinetics and multitude of GPCR signaling pathways. © FASEB.
Cisbio Bioassays | Date: 2014-01-16
The invention relates to complexing agents of formula (I): in which A, chrom1, chrom2 and chrom3 are as defined in the description. The invention also relates to the lanthanide complexes obtained from these complexing agents.
Cisbio Bioassays | Date: 2013-03-18
The invention relates to a method for determining the ability of a candidate antibody to keep a first cell and a second cell close to one another, said method comprising the following steps: The invention also relates to a reagent kit for carrying out this method.
Cisbio Bioassays | Date: 2012-07-04
The invention relates to a method for quantifying a protein of interest expressed at the surface of a cell or else present in a tissue sample, said method comprising the use of two ligands capable of binding specifically to a domain of said protein.