Biology subjects

Flynn, A. J.

Publications and source records attributed to Flynn, A. J..

4 recordsLinked to original sources

bioRxiv2025

Large-Scale Structure-Based Virtual Screening Identifies Diverse KNa1.1 (KCNT1) Potassium Channel Inhibitors

Severe drug-resistant childhood epilepsy is caused by KCNT1 gain-of-function genetic variants, resulting in increased KNa1.1 channel activity. KCNT1-associated epilepsy is thought to affect around 1 in 300,000 births worldwide. Current treatment for KCNT1 epilepsy only provides mild symptomatic relief and uses a cocktail of experimental medications which must be personalised for the individual and are often poorly tolerated. Critically, with many patients, no therapeutic benefit is achieved. We sought to address this by using large-scale virtual screening to accelerate the development of a molecule which binds directly to KCNT1 to supress overactivity. We purchased a total of 71 compounds and using a combination of fluorescent thallium flux assays and patch clamp electrophysiology, identified a series of eight structurally diverse, novel inhibitors of the KNa1.1 channel with potency in the low micromolar range. These provide potential starting points for further development of drugs to treat KCNT1-associated epilepsy. HighlightsO_LIWe have discovered a range of structurally distinct inhibitors of the KCNT1 ion channel using large-scale virtual screening C_LIO_LIThese compound exhibit selectivity for the KCNT1 channel over other related ion channels C_LIO_LIThese compounds could provide starting points for new treatments for KCNT1 related Epilepsy. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=75 SRC="FIGDIR/small/679465v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@481813org.highwire.dtl.DTLVardef@12494dforg.highwire.dtl.DTLVardef@a9f787org.highwire.dtl.DTLVardef@b9f4b9_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2025

Adhirons are efficient tools to guide antiviral ligand discovery

Adhirons are small, antibody-like proteins expressed in bacteria that bind to biological targets with high affinity. Since their discovery, Adhirons have been isolated against over 350 targets, and they can be used for many research applications. However, their therapeutic application is at present in its early stages, hence the interest in developing novel small molecules to mimic their effect. We developed a pipeline for small molecule discovery where Adhirons act as starting templates in a ligand-based virtual screening workflow. For proof of concept, we used Adhirons against two viral systems: Crimean-Congo Haemorrhagic Fever Virus and Influenza A Virus. In both cases, a hit was identified from the mimics using biophysical and cell-based assays, highlighting how Adhirons, commercial libraries and structural approaches can be combined to accelerate small molecule inhibitor discovery of viruses.

cell biology↗

bioRxiv2022

The soluble N-termini of mechanosensitive ion channels MSL8, MSL9, and MSL10 are environmentally sensitive intrinsically disordered regions with distinct biophysical characteristics

Intrinsically disordered protein regions (IDRs) are highly dynamic sequences that rapidly sample a collection of conformations. In the past several decades, IDRs have emerged as a core component of many proteomes, comprising [~]30% of all eukaryotic protein sequences. IDRs are ubiquitous throughout different biological pathways, with a notable enrichment in responses to environmental stimuli such as abiotic stress. However, the diversity of IDR-based systems that biology has evolved to respond to different stimuli is expansive, warranting the exploration of IDRs present in unique molecular contexts. Here, we identify and characterize intrinsic disorder in the soluble, cytoplasmic N-terminal domains of three members of the MscS-Like (MSL) family of mechanosensitive ion channels, MSL8, MSL9 and MSL10. In plants, MSL channels are proposed to mediate the reactions to cell swelling, pathogenic invasion, and touch. A series of bioinformatic tools unanimously predicted that the cytosolic N-termini of MSLs are intrinsically disordered. We confirmed this prediction for the N-terminus of MSL10 (MSL10N) via circular dichroism spectroscopy. MSL10N adopted a predominately helical structure when exposed to the helix-inducing compound trifluoroethanol (TFE) and underwent structural changes and alterations to homotypic interaction favorability in the presence of molecular crowding agents. Lastly, in vitro imaging of condensates indicated that MSL8N, MSL9N and MSL10N have sharply differing propensities for condensate formation both inherently and in response to salt, temperature, and molecular crowding. Altogether, these data establish the N-termini of MSL channels as intrinsically disordered regions with distinct biophysical properties and the potential to respond disparately to changes in their physiochemical environment.

biochemistry↗

bioRxiv2022

SHEPHARD: a modular and extensible software architecture for analyzing and annotating large protein datasets

The emergence of high-throughput experiments and high-resolution computational predictions has led to an explosion in the quality and volume of protein sequence annotations at proteomic scales. Unfortunately, integrating and analyzing complex sequence annotations remains logistically challenging. Here we present SHEPHARD, a software package that makes large-scale integrative protein bioinformatics trivial. SHEPHARD is provided as a stand-alone package and with a pre-compiled set of human annotations in a Google Colab notebook.

bioinformatics↗