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Prendiville, N.

Publications and source records attributed to Prendiville, N..

3 recordsLinked to original sources

Protein-ligand binding kinetics are primarily controlled by the protein, not the ligand.

Protein-ligand interactions underpin biological regulation and drug action, with both binding affinity and binding kinetics shaping functional outcomes. By analysing kinetic data for 4,311 protein-small-molecule pairs, we find that when association occurs below the diffusion-controlled limit, the rates of ligand association (kon) and dissociation (koff) are primarily determined by how the initial encounter complex reorganizes into the final bound state, and that this reorganization is governed chiefly by the intrinsic dynamic properties of the protein rather than by structural features of the ligand. Counterintuitively, therefore, koff exhibits minimal dependence on ligand structure, so that dissociation proceeds through protein-gated conformational transitions rather than through direct rupture of protein-ligand contacts. This mechanistic behaviour stands in marked contrast to that for protein-protein complexes, based on an analysis of 1,561 interactions. Together, these findings challenge prevailing assumptions regarding the molecular determinants of small-molecule binding kinetics, and have broad implications for rationally modulating protein-ligand interactions and drug-target residence times.

biochemistry↗

Kinetic Fingerprints as Mechanistic and Clinical Roadmaps Across KIT Activation States

In cancer therapy, traditional approaches often overlook the dynamic nature of drug-target interactions. We introduce kinetic fingerprints as a mechanistically informative tool to guide kinase inhibitor design and predict clinical performance. Profiling 172 compounds across multiple KIT conformations, including the oncogenic D816V mutation, show that prolonged residence time determines therapeutic success, while mutations accelerating dissociation rates (koff) drive resistance, positioning koff as a robust predictor of clinical failure. Beyond efficacy and resistance, kinetic signatures map molecular behavior: fast-associating scaffolds engage readily populated KIT states, slow binders overcome conformational barriers like juxtamembrane repositioning, and extended residence times highlight ligands stabilizing regulatory elements (G-loop and regulatory spine). Kinetic profiling further unveils mechanisms invisible to conventional methods, such as drug-induced kinase degradation, and exposes selectivity dimensions beyond affinity: avapritinib exhibits durable KIT D816V engagement yet transient off-target binding. Our findings redefine the evaluation of KIT inhibitors, establishing a framework for rational, kinetics-guided drug discovery in KIT-driven cancers. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=166 SRC="FIGDIR/small/726488v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@17f522borg.highwire.dtl.DTLVardef@1ebabc6org.highwire.dtl.DTLVardef@15a5e61org.highwire.dtl.DTLVardef@1ea5e0e_HPS_FORMAT_FIGEXP M_FIG Kinetic profiling of 172 compounds across KIT conformationsincluding D816Vreveals kinetic fingerprints that predict efficacy, selectivity, resistance, and inhibitors ability to stabilize key regulatory elements. Far from a secondary metric, binding kinetics provide mechanistic insights beyond affinity, offering a powerful framework for rational drug design in KIT-driven cancers. C_FIG

biochemistry↗

Covalent targeting leads to the development of LIMK1 isoform-selective inhibitors

Selectivity for closely related isoforms of protein kinases is a major challenge in the design of drugs and chemical probes. Covalent targeting of unique cysteines is a potential strategy to achieve selectivity for highly conserved binding sites. Here, we used a pan-LIMK inhibitor to selectively probe LIMK1 over LIMK2 by targeting the LIMK1-specific cysteine C349 located in the glycine-rich loop region. Binding kinetics of both non-covalent and covalent LIMK inhibitors were investigated, and the fast on-rate and small size of type-I inhibitors were used in the design of a covalent LIMK1 inhibitor. The developed cell-active, isoform-selective LIMK1 inhibitor showed excellent proteome-wide selectivity in pull-down assays, enabling studies of LIMK1 isoform-selective functions in cellular model systems and providing a versatile chemical tool for studies of the LIMK signalling pathway.

biochemistry↗