Fragment-based exploration of the 14-3-3/Amot-p130 interface

Curr Res Struct Biol. 2021 Dec 29;4:21-28. doi: 10.1016/j.crstbi.2021.12.003. eCollection 2022.


The modulation of protein-protein interactions (PPIs) has developed into a well-established field of drug discovery. Despite the advances achieved in the field, many PPIs are still deemed as 'undruggable' targets and the design of PPIs stabilizers remains a significant challenge. The application of fragment-based methods for the identification of drug leads and to evaluate the 'tractability' of the desired protein target has seen a remarkable development in recent years. In this study, we explore the molecular characteristics of the 14-3-3/Amot-p130 PPI and the conceptual possibility of targeting this interface using X-ray crystallography fragment-based screening. We report the first structural elucidation of the 14-3-3 binding motif of Amot-p130 and the characterization of the binding mode and affinities involved. We made use of fragments to probe the 'ligandability' of the 14-3-3/Amot-p130 composite binding pocket. Here we disclose initial hits with promising stabilizing activity and an early-stage selectivity toward the Amot-p130 motifs over other representatives 14-3-3 partners. Our findings highlight the potential of using fragments to characterize and explore proteins' surfaces and might provide a starting point toward the development of small molecules capable of acting as molecular glues.

Keywords: 14-3-3 /protein-protein interactions stabilizers; AIP4, Atrophin-1 interacting protein 4; Amot, Angiomotin; Amot-p130; AmotL1/2, Angiomotin-like 1/2; FBDD, Fragment-based drug discovery; FP, Fluorescence polarization; Fragment-based drug discovery; Lats 1/2, Large tumor suppressor 1/2; Ligandability; MST, Microscale thermophoresis; PPI, Protein-protein interaction; PTMs, post-translational modifications; X-ray crystallography; YAP1, Yes-associated protein 1.