Biology subjects

Prokofeva, P.

Publications and source records attributed to Prokofeva, P..

4 recordsLinked to original sources

bioRxiv2025

Enhanced photo-crosslinking in living cells with high-intensity longwave ultraviolet light

The activation of chemical reactions in living cells using ultraviolet (UV) light enables the interrogation of biomolecules in their native environment with photoreactive probes or crosslinking reagents. Although numerous photo-crosslinking approaches have been successfully employed, they often suffer from common limitations, including low reaction yields, the need for long exposure times, and irradiation-induced cellular damage from heat, desiccation, or side reactions. We recently showed that 365 nm light-emitting diodes (LEDs) enable rapid, bioorthogonal protein-DNA crosslinking in living cells, incurring minimal photodamage. Here we generalize this approach and demonstrate that high-intensity, longwave UV light reduces the irradiation time for in-cell photo-crosslinking reactions by up to 1000-fold, allowing protein-drug, protein-protein, protein-DNA and protein-RNA interactions to be fixed within seconds. Benchmarking this rapid photo-activation for the analysis of RNA-interacting proteomes responding to RNA-binding drugs, we demonstrate both qualitative and quantitative advantages of controlled, high-intensity UV irradiation, uncovering emergent experimental opportunities that were previously inaccessible to light-activated chemistry in intact cells and tissues.

molecular biology↗

bioRxiv2025

High-performance proteomics at any chromatographic flow rate

Current applications of mass spectrometry-based proteomics range from single cell to body fluid analysis that come with very different demands regarding sensitivity or sample throughput. Additionally, the vast molecular complexity of proteomes and the massive dynamic range of protein concentrations in these biological systems require very high-performance chromatographic separations in tandem with the high speed and sensitivity afforded by mass spectrometer. In this study, we focussed on the chromatographic angle and, more specifically, systematically evaluated proteome analysis performance across a wide range of chromatographic flow rates (0.3 - 50 L/min) and associated column diameters using a Vanquish Neo UHPLC coupled online to a Q Exactive HF-X mass spectrometer. Serial dilutions of HeLa cell line digests were used for benchmarking and total analysis time from injection-to-injection was intentionally fixed at 60 minutes (24 samples per day). The three key messages of the study are that i) all chromatographic flow rates are suitable for high-quality proteome analysis, ii) capLC (1.5 L/min) is a very robust, sensitive and quantitative alternative to nanoLC for many applications and iii) showcased proteome, phosphoproteome and drug proteome data provide sound empirical guidance for laboratories in selecting appropriate chromatographic flow rates and column diameters for their specific application.

systems biology↗

bioRxiv2024

Inhibitor-induced supercharging of kinase turnover via endogenous proteolytic circuits

Targeted protein degradation has emerged as a promising new pharmacological strategy. Traditionally, it relies on small molecules that induce proximity between a target protein and an E3 ubiquitin ligase to prompt target ubiquitination and degradation by the proteasome. Sporadic reports indicated that ligands designed to inhibit a target can also induce its destabilization. Among others, this has repeatedly been observed for kinase inhibitors. However, we lack an understanding of the frequency, generalizability, and mechanistic underpinnings of these phenomena. To address this knowledge gap, we generated dynamic abundance profiles of 98 kinases after cellular perturbations with 1570 kinase inhibitors, revealing 160 selective instances of inhibitor-induced kinase destabilization. Kinases prone to degradation are frequently annotated as HSP90 clients, thus affirming chaperone deprivation as an important route of destabilization. However, detailed investigation of inhibitor-induced degradation of LYN, BLK and RIPK2 revealed a differentiated, common mechanistic logic where inhibitors function by inducing a kinase state that is more efficiently cleared by endogenous degradation mechanisms. Mechanistically, effects can manifest by ligand-induced changes in cellular activity, localization, or multimerization which may be triggered by direct target engagement or network effects. Collectively, our data suggest that inhibitor-induced kinase degradation is a common event and positions supercharging of endogenous degradation circuits as an alternative to classical proximity-inducing degraders.

molecular biology↗

bioRxiv2023

Targeting cancer with small molecule pan-KRAS degraders

Despite the high prevalence of cancers driven by KRAS mutations, to date only the G12C mutation has been clinically proven to be druggable via covalent targeting of the mutated cysteine amino acid residue (1). However, in many cancer indications other KRAS mutations, such as G12D and -V, are far more prevalent and small molecule concepts that can address a wider variety of oncogenic KRAS alleles are in high clinical demand (2). Here we show that a single small molecule can be used to simultaneously and potently degrade 13 out of 17 of the most prevalent oncogenic KRAS alleles, including those not yet tractable by inhibitors. Compared with inhibition, degradation of oncogenic KRAS results in more profound and sustained pathway modulation across a broad range of KRAS mutant cell lines. As a result, KRAS degraders inhibit growth of the majority of cancer cell lines driven by KRAS mutations while sparing models without genetic KRAS aberrations. Finally, we demonstrate that pharmacological degradation of oncogenic KRAS leads to tumour regression in vivo. Together, these findings unveil a new path towards addressing KRAS driven cancers with small molecule degraders. One-Sentence SummaryThe most prevalent KRAS variants which drive tumour growth in a major share of cancer patients can be targeted with a single small molecule degrader.

pharmacology and toxicology↗