Targeting Oxidative Stress and Inflammation in the Eye: Insights from a New Model of Experimental Autoimmune Uveitis.

Autoimmune uveitis is a relapsing blind-causing ocular condition with complex pathogenesis that is not completely understood. There is a high demand for accurate animal models of experimental autoimmune uveitis (EAU) suitable for elucidating the molecular mechanisms of the disease and testing new therapeutic approaches. Here, we demonstrated that photoreceptor Ca/Zn-sensor protein recoverin is a uveoretinal antigen in albino rabbits provoking typical autoimmune chorioretinitis 2-4 weeks after immunization.

Exploring the Influence of Zinc Ions on the Conformational Stability and Activity of Protein Disulfide Isomerase.

The interplay between metal ion binding and the activity of thiol proteins, particularly within the protein disulfide isomerase family, remains an area of active investigation due to the critical role that these proteins play in many vital processes. This research investigates the interaction between recombinant human PDIA1 and zinc ions, focusing on the subsequent implications for PDIA1's conformational stability and enzymatic activity. Employing isothermal titration calorimetry and differential scanning calorimetry, we systematically compared the zinc binding capabilities of both oxidized and reduced forms of PDIA1 and assessed the structural consequences of this interaction.

Plasma nanoDSF Denaturation Profile at Baseline Is Predictive of Glioblastoma EGFR Status.

Glioblastoma (GBM) is the most frequent and aggressive primary brain tumor in adults. Recently, we demonstrated that plasma denaturation profiles of glioblastoma patients obtained using Differential Scanning Fluorimetry can be automatically distinguished from healthy controls with the help of Artificial Intelligence (AI). Here, we used a set of machine-learning algorithms to automatically classify plasma denaturation profiles of glioblastoma patients according to their EGFR status.

Myotoxin-3 from the Pacific Rattlesnake Venom Is a New Microtubule-Targeting Agent.

Microtubule targeting agents (MTA) are anti-cancer molecules that bind tubulin and interfere with the microtubule functions, eventually leading to cell death. In the present study, we used an in vitro microtubule polymerization assay to screen several venom families for the presence of anti-microtubule activity. We isolated myotoxin-3, a peptide of the crotamine family, and three isoforms from the venom of the Northern Pacific rattlesnake , which was able to increase tubulin polymerization.

Binding of two zinc ions promotes liquid-liquid phase separation of Tau.

Tau is a naturally disordered microtubule associated protein which forms intraneuronal aggregates in several neurodegenerative diseases including Alzheimer's disease (AD). It was reported that zinc interaction with tau protein can trigger its aggregation. Recently we identified three zinc binding sites located in the N-terminal part, repeat region and the C-terminal part of tau.

APOE4 drives inflammation in human astrocytes via TAGLN3 repression and NF-κB activation.

Apolipoprotein E4 (APOEε4) is the major allelic risk factor for late-onset sporadic Alzheimer's disease (sAD). Inflammation is increasingly considered as critical in sAD initiation and progression. Identifying brain molecular mechanisms that could bridge these two risk factors remain unelucidated.

Zinc Modulation of Neuronal Calcium Sensor Proteins: Three Modes of Interaction with Different Structural Outcomes.

Neuronal calcium sensors (NCSs) are the family of EF-hand proteins mediating Ca-dependent signaling pathways in healthy neurons and neurodegenerative diseases. It was hypothesized that the calcium sensor activity of NCSs can be complemented by sensing fluctuation of intracellular zinc, which could further diversify their function. Here, using a set of biophysical techniques, we analyzed the Zn-binding properties of five proteins belonging to three different subgroups of the NCS family, namely, VILIP1 and neurocalcin-δ/NCLD (subgroup B), recoverin (subgroup C), as well as GCAP1 and GCAP2 (subgroup D).

Identification of the three zinc-binding sites on tau protein.

Tau protein has been extensively studied due to its key roles in microtubular cytoskeleton regulation and in the formation of aggregates found in some neurodegenerative diseases. Recently it has been shown that zinc is able to induce tau aggregation by interacting with several binding sites. However, the precise location of these sites and the molecular mechanism of zinc-induced aggregation remain unknown.

Mechanism of Zn and Ca Binding to Human S100A1.

S100A1 is a member of the S100 family of small ubiquitous Ca-binding proteins, which participates in the regulation of cell differentiation, motility, and survival. It exists as homo- or heterodimers. S100A1 has also been shown to bind Zn, but the molecular mechanisms of this binding are not yet known.

Disulfide Dimerization of Neuronal Calcium Sensor-1: Implications for Zinc and Redox Signaling.

Neuronal calcium sensor-1 (NCS-1) is a four-EF-hand ubiquitous signaling protein modulating neuronal function and survival, which participates in neurodegeneration and carcinogenesis. NCS-1 recognizes specific sites on cellular membranes and regulates numerous targets, including G-protein coupled receptors and their kinases (GRKs). Here, with the use of cellular models and various biophysical and computational techniques, we demonstrate that NCS-1 is a redox-sensitive protein, which responds to oxidizing conditions by the formation of disulfide dimer (dNCS-1), involving its single, highly conservative cysteine C38.

An AI-Powered Blood Test to Detect Cancer Using NanoDSF.

Glioblastoma is the most frequent and aggressive primary brain tumor. Its diagnosis is based on resection or biopsy that could be especially difficult and dangerous in the case of deep location or patient comorbidities. Monitoring disease evolution and progression also requires repeated biopsies that are often not feasible.

Stoichiometry of irreversible ligand binding to a one-dimensional lattice.

In this paper we investigate the problem of irreversible binding of a ligand that covers several identical binding sites on a macromolecule with a one-dimensional lattice. Due to steric constraints, irreversible binding or binding with slow kinetics results in partial saturation of the binding sites thus impacting the stoichiometry of the interaction. Here we present a recursive formula to calculate the exact fraction of the occupied binding sites for a ligand and macromolecule of arbitrary lengths.

Zinc Binds to RRM2 Peptide of TDP-43.

Transactive response DNA and RNA binding protein 43 kDa (TDP-43) is a highly conserved heterogeneous nuclear ribonucleoprotein (hnRNP), which is involved in several steps of protein production including transcription and splicing. Its aggregates are frequently observed in motor neurons from amyotrophic lateral sclerosis patients and in the most common variant of frontotemporal lobar degeneration. Recently it was shown that TDP-43 is able to bind Zn by its RRM domain.

In silico molecular target prediction unveils mebendazole as a potent MAPK14 inhibitor.

The concept of polypharmacology involves the interaction of drug molecules with multiple molecular targets. It provides a unique opportunity for the repurposing of already-approved drugs to target key factors involved in human diseases. Herein, we used an in silico target prediction algorithm to investigate the mechanism of action of mebendazole, an antihelminthic drug, currently repurposed in the treatment of brain tumors.

Role of Tau as a Microtubule-Associated Protein: Structural and Functional Aspects.

Microtubules (MTs) play a fundamental role in many vital processes such as cell division and neuronal activity. They are key structural and functional elements in axons, supporting neurite differentiation and growth, as well as transporting motor proteins along the axons, which use MTs as support tracks. Tau is a stabilizing MT associated protein, whose functions are mainly regulated by phosphorylation.

Characterization of Microtubule-Associated Proteins (MAPs) and Tubulin Interactions by Isothermal Titration Calorimetry (ITC).

Microtubules are highly dynamic structures which play a central role in many cellular processes such as cell division, intracellular transport, and migration. Their dynamics is tightly regulated by stabilizing and destabilizing microtubule-associated proteins (MAPs), such as tau and stathmin. Many approaches have been developed to study interactions between tubulin and MAPs.

Plasmatic Signature of Disease by Differential Scanning Calorimetry (DSC).

Differential scanning calorimetry (DSC) has been used for several decades to characterize thermal stability of macromolecules such as proteins and DNA. It allows to determine the denaturation temperature and enthalpy of individual domains of proteins, thus giving new insights into their domain organization and ligand interaction. Over the past decade, it has been shown that this technique can also be used to study biofluids such as plasma or cerebrospinal fluid to obtain denaturation profiles.

The elusive tau molecular structures: can we translate the recent breakthroughs into new targets for intervention?

Insights into tau molecular structures have advanced significantly in recent years. This field has been the subject of recent breakthroughs, including the first cryo-electron microscopy structures of tau filaments from Alzheimer's and Pick's disease inclusions, as well as the structure of the repeat regions of tau bound to microtubules. Tau structure covers various species as the tau protein itself takes many forms.

Functional Status of Neuronal Calcium Sensor-1 Is Modulated by Zinc Binding.

Neuronal calcium sensor-1 (NCS-1) protein is abundantly expressed in the central nervous system and retinal neurons, where it regulates many vital processes such as synaptic transmission. It coordinates three calcium ions by EF-hands 2-4, thereby transducing Ca signals to a wide range of protein targets, including G protein-coupled receptors and their kinases. Here, we demonstrate that NCS-1 also has Zn-binding sites, which affect its structural and functional properties upon filling.

Zinc Induces Temperature-Dependent Reversible Self-Assembly of Tau.

Tau is an intrinsically disordered microtubule-associated protein that is implicated in several neurodegenerative disorders called tauopathies. In these diseases, Tau is found in the form of intracellular inclusions that consist of aggregated paired helical filaments (PHFs) in neurons. Given the importance of this irreversible PHF formation in neurodegenerative disease, Tau aggregation has been extensively studied.

Differential scanning calorimetry of plasma in glioblastoma: toward a new prognostic / monitoring tool.

Glioblastoma is the most frequent and aggressive primary brain tumor in adults. Recently, a growing number of studies have shown that denaturation profile of plasma samples obtained by differential scanning calorimetry (DSC) can represent a signature of a disease. In this study, we analyzed for the first time the DSC denaturation profiles of the plasma from patients with recurrent glioblastoma (n=17).

Zinc binding to RNA recognition motif of TDP-43 induces the formation of amyloid-like aggregates.

Aggregation of TDP-43 (transactive response DNA binding protein 43 kDa) is a hallmark of certain forms of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Moreover, intracellular TDP-43-positive inclusions are often found in other neurodegenerative diseases. Recently it was shown that zinc ions can provoke the aggregation of endogenous TDP-43 in cells, allowing to assume a direct interaction of TDP-43 with zinc ions.

Bacterial co-expression of human Tau protein with protein kinase A and 14-3-3 for studies of 14-3-3/phospho-Tau interaction.

Abundant regulatory 14-3-3 proteins have an extremely wide interactome and coordinate multiple cellular events via interaction with specifically phosphorylated partner proteins. Notwithstanding the key role of 14-3-3/phosphotarget interactions in many physiological and pathological processes, they are dramatically underexplored. Here, we focused on the 14-3-3 interaction with human Tau protein associated with the development of several neurodegenerative disorders, including Alzheimer's and Parkinson's diseases.

Oxidation of Са2+-Binding Domain of NADPH Oxidase 5 (NOX5): Toward Understanding the Mechanism of Inactivation of NOX5 by ROS.

NOX5 protein, one of the most active generators of reactive oxygen species (ROS), plays an important role in many processes, including regulation of cell growth, death and differentiation. Because of its central role in ROS generation, it needs to be tightly regulated to guarantee cellular homeostasis. Contrary to other members of NADPH-oxidases family, NOX5 has its own regulatory calcium-binding domain and thus could be activated directly by calcium ions.