The p53 and Mouse double minute 2 (MDM2) proteins are hubs in extensive networks of interactions with multiple partners and functions. Intrinsically disordered regions help to adopt function-specific structural conformations in response to ligand binding and post-translational modifications. Different techniques have been used to dissect interactions of the p53-MDM2 pathway, in vitro, in vivo, and in situ each having its own advantages and disadvantages. This review uses the p53-MDM2 to show how different techniques can be employed, illustrating how a combination of in vitro and in vivo techniques is highly recommended to study the spatio-temporal location and dynamics of interactions, and to address their regulation mechanisms and functions. By using well-established techniques in combination with more recent advances, it is possible to rapidly decipher complex mechanisms, such as the p53 regulatory pathway, and to demonstrate how protein and nucleotide ligands in combination with post-translational modifications, result in inter-allosteric and intra-allosteric interactions that govern the activity of the protein complexes and their specific roles in oncogenesis. This promotes elegant therapeutic strategies that exploit protein dynamics to target specific interactions.

Biochemistry Molecular Biology Faculty of Science Universidad de la República Iguá 4225 Montevideo 11400 Uruguay

Department of Medical Biosciences Building 6M Umeå University 90185 Umeå Sweden

Inserm UMRS1131 Institut de Génétique Moléculaire Université Paris 7 Hôpital St Louis F 75010 Paris France

International Center for Cancer Vaccine Science University of Gdańsk Science ul Wita Stwosza 63 80 308 Gdańsk Poland

Laboratorio de Interacciones Biomoleculares y Cáncer Instituto de Física Universidad Autónoma de San Luis Potosí Manuel Nava 6 Zona Universitaria San Luis Potosí 78290 Mexico

Regional Centre for Applied Molecular Oncology Masaryk Memorial Cancer Institute Zluty Kopec 7 65653 Brno Czech Republic

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