Abstract: The present invention relates to a method for detecting protein-protein interactions by assessing interaction in a eukaryotic cell of a first fusion protein that specifically binds to GFP and accumulates at distinct sites in the nucleus of the cell or interacts with structures accumulated at distinct sites in the nucleus of the cell; a second fusion protein comprising GFP and a bait (poly)peptide; and a third fusion protein comprising a fluorescent (poly)peptide having an excitation and/or emission wavelength that differs from that of GFP and a prey (poly)peptide. The emissions from the fluorescent parts of the fusion proteins are observed. Co-localization of the emissions from both fluorescent fusion proteins indicates interaction of the bait and the prey (poly)peptide. Methods for identifying a compound modulating the interaction of two (poly)peptides and methods of determining the relative strength of the interaction of two proteins with a third protein.

Abstract: The present invention relates to an in vitro method for detecting protein-protein interactions comprising: (a) expressing in a eukaryotic cell a first fusion protein comprising (i) a (poly)peptide that, when expressed in a cell, accumulates at distinct sites in the nucleus of the cell or interacts with proteinaceous or non-proteinaceous structures accumulated at distinct sites in the nucleus of the cell; and (ii) a (poly)peptide specifically binding to GFP; (b) expressing in the same cell a second fusion protein comprising (i) GFP; and (ii) a bait (poly)peptide; (c) expressing in the same cell a third fusion protein comprising (i) a fluorescent (poly)peptide, the excitation and/or emission wavelength of which differs from that of GFP; and (ii) a prey (poly)peptide; and (d) detecting the fluorescence emission of the fluorescent parts of the second and the third fusion protein in the cell upon excitation, wherein a co-localization of the fluorescence emission of both fusion proteins in the cell nucleus is indic

Abstract: The present invention relates to an in vitro method for detecting protein-protein interactions comprising: (a) expressing in a eukaryotic cell a first fusion protein comprising (i) a (poly)peptide that, when expressed in a cell, accumulates at distinct sites in the nucleus of the cell or interacts with proteinaceous or non-proteinaceous structures accumulated at distinct sites in the nucleus of the cell; and (ii) a (poly)peptide specifically binding to GFP; (b) expressing in the same cell a second fusion protein comprising (i) GFP; and (ii) a bait (poly)peptide; (c) expressing in the same cell a third fusion protein comprising (i) a fluorescent (poly)peptide, the excitation and/or emission wavelength of which differs from that of GFP; and (ii) a prey (poly)peptide; and (d) detecting the fluorescence emission of the fluorescent parts of the second and the third fusion protein in the cell upon excitation, wherein a co-localization of the fluorescence emission of both fusion proteins in the cell nucleus is indic