Title: Discovery, characterisation and therapeutic targetting of motif-mediated interactions regulating cell cycle progression
Funder: Cancer Research UK

Abstract: Background: A vast array of cell cycle regulators monitor the order, integrity, and fidelity of the key events that guide the cell from quiescence through cell growth to proliferation. Several kinase and microtubule inhibitor cancer drugs (e.g. Chk1-inhibitor ICP-1 and the SAC-activating Taxanes) targeting these cell cycle regulators have shown that the cell cycle checkpoints can be exploited in our fight against cancer. The molecular details of many of the major protein-protein interactions controlling the robustness of cell cycle progression have accumulated through years of small-scale analyses. However, there exist significant gaps in our understanding of the cell cycle, particular regarding the functional role of the vast intrinsically disordered regions (IDRs) of cell cycle-related proteins. Consequently, these regions remain an unexplored space for therapeutic intervention in the treatment of cancer. Aims: We propose a high-throughput integrative omics approach to (i) discover and characterise the functional elements in the IDRs of cell cycle regulators on the molecular level and (ii) test the therapeutic potential of inhibition of interactions mediated by these functional elements to discover novel cancer drug leads. The goal of the proposal is to produce (i) an amino acid resolution map of the IDR-mediated interactome of the key cell cycle regulators and (ii) a set of IDR-mediated interactions for further in-depth validation as cancer drug targets. Methods: We will apply cutting-edge PPI discovery methods optimised for interaction interfaces in IDRs. The approach will utilise four complementary approaches: in vivo cross-linking AP-MS (XAP-MS); in vivo tandem motif peptide AP-MS (TMAP-MS); in vitro proteomic phage display (Pro-PD); and in silico motif-binding pocket specificity modelling. We will create and validate specific inhibitors targeting the characterised IDR-binding pockets of the key cell cycle regulators using tandem motif ‘superbinder’ inhibitors. We will then screen these inhibitors for therapeutically relevant activity with classical drug screening methodologies. How the results of this research will be used: Firstly, the amino acid resolution map of the IDR-mediated interactome of the key cell cycle regulators will drive a wide range of projects that could result in fundamental discoveries in the field of cell cycle biology. Secondly, the drug leads identified by the project will be further validated and optimised at the ICR. If successful, this research will open a novel area for drug discovery and potentially result in a novel class of anti-cancer drugs for use in the clinic.

Lay abstract: Background: A vast array of cell cycle regulators monitor the order, integrity, and fidelity of the key events that guide the cell from quiescence through cell growth to proliferation. Several drugs targeting these cell cycle regulators have shown that the cell cycle checkpoints can be exploited in our fight against cancer. The molecular details of many of the major protein-protein interactions controlling the robustness of cell cycle progression have accumulated through years of small-scale analyses. However, there exist significant gaps in our understanding of the cell cycle, particular regarding the functional role of the vast intrinsically disordered regions (IDRs) of cell cycle-related proteins. Consequently, these regions remain an unexplored space for therapeutic intervention in the treatment of cancer. Aims: We propose a high-throughput integrative omics approach to (i) discover and characterise the functional elements in the IDRs of cell cycle regulators on the molecular level and (ii) test the therapeutic potential of inhibition of interactions mediated by these functional elements to discover novel cancer drug targets. The goal of the proposal is to produce (i) an amino acid resolution map of the IDR-mediated interactome of the key cell cycle regulators and (ii) a set of IDR-mediated interactions for further in-depth validation as cancer drug targets. Methods: We will apply cutting-edge PPI analysis methods optimised to discover and characterise interaction interfaces in IDRs. The approach will utilise four complementary approaches: in cell cross-linking AP-MS (XAP-MS); in cell tandem motif peptide AP-MS (TMAP-MS); in vitro proteomic peptide phage display (ProP-PD); and in silico motif-binding pocket specificity modelling. We will then design and validate specific peptide inhibitors targeting the characterised IDR-binding pockets of the key cell cycle regulators using tandem motif ‘superbinder’ inhibitors. Finally, we will screen these peptide inhibitors for therapeutically relevant activity with classical drug screening methodologies. How the results of this research will be used: Firstly, the amino acid resolution map of the IDR-mediated interactome of the key cell cycle regulators will drive a wide range of projects that could result in fundamental discoveries in the field of cell cycle biology. Secondly, the drug leads identified by the project will be further validated and optimised at the ICR. If successful, this research will open a novel area for drug discovery and potentially result in a novel class of anti-cancer drugs for use in the clinic.

Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS;5.1 PHARMACEUTICALS
Health categories: CANCER AND NEOPLASMS