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Structural Assessment of the Full-Length Tumor Suppressor Protein p53 by Mass Spectrometry-Guided Computational Modeling

ABSTRACT: The tetrameric tumor suppressor p53 represents a great challenge for 3D structural analysis due to its high degree of intrinsic disorder (ca. 40%). We developed and applied an integrative structural biology approach combining complementary techniques of structural mass spectrometry (MS), namely cross-linking mass spectrometry (XL-MS), protein footprinting, and hydrogen/deuterium exchange mass spectrometry (HDX-MS), with advanced protein structure prediction approaches to gain insights into the disordered C-terminal region of p53. Additionally, we evaluate possible differences in p53 regarding solvent accessibility and topology upon DNA binding. Our quantitative XL-MS and lysine labeling data show no major conformational differences in p53 between DNA-bound and DNA-free states. Integration of experimental data generate p53 models for p53’s intrinsically disordered regions (IDRs) that reflect substantial compaction of the molecule. Our models provide the most detailed description of the relationship between p53’s folded regions and IDRs that is available to date. The synergies between complementary structural MS techniques and computational modeling as pursued in our integrative approach is envisioned to serve as general strategy for studying intrinsically disordered proteins (IDPs) and IDRs.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Escherichia Coli

SUBMITTER: Alessio Di Ianni

LAB HEAD: Andrea Sinz

PROVIDER: PXD037030 | Pride | 2023-06-26

REPOSITORIES: Pride

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