摘要:
The invention relates to a method that makes it possible to predetermine if a compound to be tested preferably binds to a membrane receptor R1 or to a membrane receptor R2, said receptors being known to be expressed as a monomeric, homodimeric, or heterodimeric receptor on the surface of cells. Said method is implemented through the use of one or two FRET partner pairs.
摘要:
The invention relates to a method for detection of ligands (agonists or antagonists) specific to a receptor (RCPG) coupled to a G protein, comprising the following steps; 1) bring a receptor marked with a member of a donor/acceptor pair into contact with a Gα or Gß? sub-unit of a G protein marked with the other member of the donor/acceptor pair and 2) measure the transfer by proximity effect between the donor and acceptor. The above is of application to the screening of novel medicaments.
摘要:
The invention relates to a method for selecting compounds having a modulating effect on the activation state of a dimer of VFT domain proteins expressed in cellular membranes in a measuring medium, said dimer including a first protein and a second protein which are identical or different, wherein the method includes the following steps: (a) marking the first and second proteins in the N-terminal portion of the VFT domain by members of a FRET partner pair, the Förster radius (R 0 ) of said pair ranging between 20 and 55 Å; (b) measuring the FRET signal in the absence and in the presence of the compound to be tested within a predetermined time window; (c) selecting the compound to be tested as a modulating compound if a difference in the FRET signal in the absence and in the presence of the compound to be tested is measured during step (b). The invention can be used in the research for new drugs and new taste modulators.
摘要:
The invention relates to inositol-phosphate derivatives, in which the inositol-phosphate is substituted by one or two reactive groups G or one or two conjugated molecules M or substances, said reactive group(s) G or said substance(s) or molecule(s) M being linked to IPI via a linkage group L. According to the invention, M is selected from the following group: a tracer, an immunogen, a member of a pair of binding partners, a solid support. The invention is suitable for tools that are used to study the cycle of inositols-phosphates and thus, indirectly, to study seven-domain transmembrane receptors that are coupled to the phospholipase C, receptors having a tyrosine-kinase activity and, generally, enzymes involved in variations in IPI intracellular concentration.
摘要:
A method for detecting the internalization of a transmembrane protein of interest expressed at the surface of a cell, comprising the following steps: a) labelling the protein of interest with a fluorescent metal complex, the lifetime of which is greater than 0.1 ms; b) adding to the reaction medium a composition capable of causing the internalization of the protein of interest; c) adding to the reaction medium a modulating agent selected from: a. a fluorescent or nonfluorescent FRET acceptor compound compatible with said fluorescent metal complex, the final concentration of which in the reaction medium is greater than 10 ‑7 M; b. a reducing agent, the redox potential of which is less than +0.1 V and preferably between 0.25 and 0.75 V; c. an agent which binds specifically, by noncovalent bonding, with the fluorescent metal complex; d. a metal ion which competes with the rare earth so as to form a nonfluorescent metal complex; d) measuring the luminescence emitted by the reaction medium at the emission wavelength of the fluorescent metal complex and/or at the emission wavelength of the modulating compound when said compound is a fluorescent acceptor compound; e) comparing the signal measured in step d) with a reference signal measured on cells having been subjected only to steps a) and c). Use: Method for detecting membrane protein internalization.
摘要:
Method for the detection in homogeneous medium of a post-translational modification of a protein substrate catalyzed by a cell enzyme, characterized in that the post-translational modification reaction takes place in intact living cells, in that these cells comprise a heterologous expression vector coding for a fusion protein comprising the protein substrate and a first coupling domain and in that it comprises the following stages: (v) Incubation of the cells in the presence or in the absence of a compound to be tested capable of modulating the activity of said enzyme, (vi) Addition to the reaction medium of a first fluorescent compound member of a first pair of FRET partners covalently bonded to a coupling agent capable of binding specifically to the first coupling domain present on the protein substrate, (vii) Addition to the reaction medium of a second fluorescent compound member of this first pair of FRET partners, and covalently bonded to a binding domain specific to the site of the protein substrate having undergone the post-translational modification and not binding to the non-modified protein substrate, (i) Measurement of the FRET signal emitted by the sample, this signal being representative of the quantity of protein substrate having undergone said post-translational modification; and cells for the implementation of said method.