INtraCELLular delivery of PHOSphorylated tools to TAG proteins using next generation nucleoside triphosphate derivatives

• Applicant: Professor Dr. Chris Meier
• Subject Area: Biological and Biomimetic Chemistry ; Cell Biology
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426328168

Drug discovery heavily relies on assay technologies which analyze and monitor the physiological situation in human cell, in order to faithfully identify potent and selective modulators of disease processes. These modulators, whether they are small molecules, peptides or antibodies, all require pharmacologically relevant in-vitro assays to be used for quantification of their modulatory effects. Many approaches using in-vitro systems and overexpression of target proteins in heterologous cell types have often led to spectacular failures of drug candidates in later stages of clinical development. This is due to an intrinsic lack of biological relevance, in the test assay systems, to key disease efficacy and toxicological properties.We here aim to deliver a sensitive, consistent and accurate assay technology which enables the interrogation of key cellular drug targets in relevant live cell formats. The technology will be applied to major drug target classes including G-protein coupled receptors (GPCR) and protein kinases (PK) which are targeted by 30% and 6% of marketed drugs, respectively. Available assay technology is historically build on radiolabeled reagents, which is undesirable, and largely lacks applicability in physiological contexts, especially as reagents aren’t able to cross intact cell membranes.Our consortium combines unique expertise in generating cell-permeable, modified nucleoside triphosphate (NTP) substrates (TriPPPro technology), extensive experience in establishing and adapting cell-based assays for high throughput screening campaigns and in applying human induced pluripotent stem cell (hiPSC) technology to early stage (target-to-lead) drug discovery. In addition, we have access to state-of-the-art screening technology, access to several 100,000 "ready-to-screen" compounds and bring in the knowledge and experience of one of the leading companies world-wide providing assay technology to all major pharmaceutical companies.In the proposed project, we will generate novel NTP-derivatives that carry gamma-phosphate modifications for covalently labeling targets of interest in combination with a biodegradable masking moiety that enables cell membrane permeation. These compounds’ performance as live cell assay reagents will be interrogated focusing on specific G-protein or kinase functionalities in relevant physiological models, especially hiPS-cardiomyocytes, to finally yield a validated assay technology. This novel technology will be broadly applicable and has the potential to advance both basic research related to understanding disease mechanisms and industrial drug discovery once it has been successfully established on the market in “ready to use” commercial kit formats.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: PerkinElmer Inc.
• Cooperation Partners: Professor Dr. Gerd Geisslinger; Dr. Ole Pless