Abstract: The present invention relates to compounds comprising a polypeptide comprising an amino acid sequence derived from the sequence of a cyclin-dependent kinase (CDK) and at least one fluorophore coupled to an amino acid of said polypeptide. The invention also relates to said compounds associated with a technology enabling their intracellular delivery. The present invention also relates to the use of such compounds, or of compositions comprising said compounds, for determining if a product is capable of modulating the conformation of a CDK. More particularly, a compound according to the invention is usable for high-content high-throughput screening.

Abstract: This invention relates to compounds comprising a polypeptide and a fluorophore, wherein the polypeptide is capable of being phosphorylated by a Cyclin-Dependent Kinase (CDK) and/or a Cyclin-CDK complex on a specific site and wherein the fluorescence of said fluorophore changes upon phosphorylation of said specific site of said polypeptide. The invention also relates to the use of such compounds or of compositions comprising such compounds for medical imaging. The invention furthermore relates to methods for determining if at least one CDK and/or Cyclin-CDK complex is active, for determining changes in at least one CDK and/or Cyclin-CDK complex activity, for the in vitro diagnosis of Cyclin-dependent kinase hyperactivation in a subject.