Publications by authors named "Willmore L"

Article Synopsis
  • Some individuals react differently to chronic stress, with some being more susceptible while others display resilience.
  • This study focuses on the lateral habenula (LHb), which is involved in signaling negative outcomes, to see how its activity differs between susceptible and resilient mice during stress.
  • Findings reveal that susceptible mice exhibit increased LHb activity during stress, particularly when near aggressors, leading to long-lasting effects on brain activity and behavior that promote further susceptibility.
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Article Synopsis
  • - The study investigates how different mice respond to chronic stress, focusing on the lateral habenula (LHb), which is linked to negative learning signals.
  • - Researchers found that susceptible mice show greater LHb activity when near aggressive mice after experiencing social defeat stress, contributing to their susceptibility.
  • - The increased LHb activity during stress leads to widespread changes in brain function in susceptible mice, resulting in lasting impacts on their behavior and neural responses.
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The introduction of AlphaFold 2 has spurred a revolution in modelling the structure of proteins and their interactions, enabling a huge range of applications in protein modelling and design. Here we describe our AlphaFold 3 model with a substantially updated diffusion-based architecture that is capable of predicting the joint structure of complexes including proteins, nucleic acids, small molecules, ions and modified residues. The new AlphaFold model demonstrates substantially improved accuracy over many previous specialized tools: far greater accuracy for protein-ligand interactions compared with state-of-the-art docking tools, much higher accuracy for protein-nucleic acid interactions compared with nucleic-acid-specific predictors and substantially higher antibody-antigen prediction accuracy compared with AlphaFold-Multimer v.

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Protein tyrosine phosphatase SHP2 mediates RAS-driven MAPK signaling and has emerged in recent years as a target of interest in oncology, both for treating with a single agent and in combination with a KRAS inhibitor. We were drawn to the pharmacological potential of SHP2 inhibition, especially following the initial observation that drug-like compounds could bind an allosteric site and enforce a closed, inactive state of the enzyme. Here, we describe the identification and characterization of (formerly RLY-1971), a SHP2 inhibitor currently in clinical trials in combination with KRAS G12C inhibitor divarasib (GDC-6036) for the treatment of solid tumors driven by a KRAS G12C mutation.

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Dopamine neurons of the ventral tegmental area (VTA) respond to food and social stimuli and contribute to both forms of motivation. However, it is unclear whether the same or different VTA neurons encode these different stimuli. To address this question, we performed two-photon calcium imaging in mice presented with food and conspecifics and found statistically significant overlap in the populations responsive to both stimuli.

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Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of the insulin and leptin signaling pathways, making it a highly attractive target for the treatment of type II diabetes. For PTP1B to perform its enzymatic function, a loop referred to as the "WPD loop" must transition between open (catalytically incompetent) and closed (catalytically competent) conformations, which have both been resolved by X-ray crystallography. Although prior studies have established this transition as the rate-limiting step for catalysis, the transition mechanism for PTP1B and other PTPs has been unclear.

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Dopamine neurons of the ventral tegmental area (VTA ) respond to food and social stimuli and contribute to both forms of motivation. However, it is unclear if the same or different VTA neurons encode these different stimuli. To address this question, we performed 2-photon calcium imaging in mice presented with food and conspecifics, and found statistically significant overlap in the populations responsive to both stimuli.

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Fragment-based drug discovery has led to six approved drugs, but the small sizes of the chemical fragments used in such methods typically result in only weak interactions between the fragment and its target molecule, which makes it challenging to experimentally determine the three-dimensional poses fragments assume in the bound state. One computational approach that could help address this difficulty is long-timescale molecular dynamics (MD) simulations, which have been used in retrospective studies to recover experimentally known binding poses of fragments. Here, we present the results of long-timescale MD simulations that we used to prospectively discover binding poses for two series of fragments in allosteric pockets on a difficult and important pharmaceutical target, protein tyrosine phosphatase 1b (PTP1b).

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Chronic stress can have lasting adverse consequences in some individuals, yet others are resilient to the same stressor. Susceptible and resilient individuals exhibit differences in the intrinsic properties of mesolimbic dopamine (DA) neurons after the stressful experience is over. However, the causal links between DA, behaviour during stress and individual differences in resilience are unknown.

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A "fragment hit", a molecule of low molecular weight that has been validated to bind to a target protein, can be an effective chemical starting point for a drug discovery project. Our ability to find and progress fragment hits could potentially be improved by enhancing our understanding of their binding properties, which to date has largely been based on tacit knowledge and reports from individual projects. In the work reported here, we systematically analyzed the molecular and binding properties of fragment hits using 489 published protein-fragment complexes.

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The need for automated and efficient systems for tracking full animal pose has increased with the complexity of behavioral data and analyses. Here we introduce LEAP (LEAP estimates animal pose), a deep-learning-based method for predicting the positions of animal body parts. This framework consists of a graphical interface for labeling of body parts and training the network.

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Mapping of protein-protein interactions (PPIs) is critical for understanding protein function and complex biological processes. Here, we present DULIP, a dual luminescence-based co-immunoprecipitation assay, for systematic PPI mapping in mammalian cells. DULIP is a second-generation luminescence-based PPI screening method for the systematic and quantitative analysis of co-immunoprecipitations using two different luciferase tags.

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Treatment of patients with epilepsy strives for complete seizure control without intolerable drug side effects. Independent of blood drug levels, toxic effects allow titration to efficacy; however, allergic reactions, metabolically or genetically determined drug-induced illnesses, and idiosyncratic effects of drugs, while rare, may be life-threatening.Monitoring is an attempt to detect serious systemic toxic reactions of antiepileptic drugs in time to intervene and protect patients.

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Traumatic brain injury occasionally causes posttraumatic epilepsy. To elucidate the molecular events responsible for posttraumatic epilepsy, we established a rodent model that involved the injection of microliter quantities of FeCl3 solution into the amygdalar nuclear complex. We previously compared hippocampal gene expression profiles in the traumatic epilepsy model and normal rats at 5 days after brain injury (acute phase) to determine the role of inflammation.

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Text of Abstract Liability to develop posttraumatic epilepsy (PTE) correlates in a general way with trauma dose. While contusion of the brain produces an admixture of extravasated blood, edema fluid and necrotic tissue at the site of skull trauma and in regions remote from the direct force, an unpredictable cascade of shearing injury, torsion and rotation and a myriad of physiological changes occur in structures subject to the mechanical pressure wave. Animal models mimic components of injury, some more thoroughly than others.

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Endoplasmic reticulum (ER) is an organelle responsible for correct folding and sorting of proteins contributing to neurogenesis and neuronal cell death. We used rapid kindling to analyze specific ER stress marker expression underlying focal epileptogenesis. Seven-week-old rats were divided into three groups: sham (n = 6), partially kindled (n = 8), and over-kindled rats (n = 9).

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In the present study, we performed comprehensive gene expression and gene network analyses using a DNA microarray to elucidate the molecular events responsible for the pathology of posttraumatic epilepsy at the partial seizure stage. We used an experimental posttraumatic epilepsy model of amygdalar focal FeCl(3)-injected rats and compared gene expression profiles in the hippocampus at the partial seizure stage (less than stage 3 on Racine's convulsion scale) and that of sham-operated animals. At the partial seizure stage, upregulation of phospholipase A2 (PLA2) and lipid metabolism were observed, which have been reported to be caused by brain injury and seizures in previous studies.

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Using pentylenetetrazol (PTZ) kindling, we collected hippocampal tissue from standard response and kindling resistant animals, measuring hippocampal mRNA with real-time PCR of glutamate transporters GLAST, GLT-1, and EAAC1 and the sodium-coupled neutral amino acid transporter (SNAT) 1, SNAT2, and SNAT3. In addition, we measured mRNA of glutamine synthetase (GS), phosphate-activated glutaminase (PAG), glutamic acid decarboxylase (GAD) 1, GAD2, and vesicular inhibitory amino acid transporter (VIAAT). Fully kindled animals had decreased expression of mRNA in the hippocampus for GLAST and GAD2 compared with saline injected control.

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Treatment of absence epilepsy requires understanding the efficacy and side effects of several drugs, one of which first became available more than 50 years ago. Methods for drug development and procedures for evaluating their safety and efficacy over that time have changed dramatically. Observational studies of the efficacy of ethosuximide, a drug developed in the 1950s, reported complete seizure control in 40-60% of patients.

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We have attempted to explore the neuroprotective effectiveness of levetiracetam (LEV) by measuring its in vivo antioxidant effect in the hippocampus of rats in a freely moving state. Male Wistar rats were used for the estimation of the in vivo antioxidant effect of LEV through microdialysis combined with electron spin resonance spectroscopy. The antioxidant effect was examined using the principle by which a systemically administered blood-brain barrier-permeable nitroxide radical (PCAM) decreases in an exponential decay manner that is correlated with the amount of antioxidant in the brain.

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Unlabelled: Vigabatrin (VGB) is a structural analogue of gamma-aminobutyric acid (GABA) that irreversibly inhibits GABA-transaminase (GABA-T), increasing brain levels of GABA. VGB is under assessment for treatment of infantile spasms (IS) and refractory complex partial seizures (CPS). Response can be rapid with spasm cessation following approximately 2 weeks of therapy.

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Kindling is a form of epileptogenesis that can be induced with pentylenetetrazol (PTZ). We undertook this study to evaluate the contribution of glutamate and GABA transporters to the process of PTZ kindling. Rats were injected i.

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