Signaling Processes Research Articles

Calcium Signaling and Molecular Adhesion Processes May Hold the Key to Genetic Risk for Autism: A Molecular Pathway Analysis on Two Independent Samples

Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by limited interests, difficulties in social interactions, repetitive behaviors, and impairments in social communication. ASD tends to run in families, and twin studies suggest a strong genetic basis for the disorder. However, the definition of a genetic profile that indicates a risk for ASD remains unclear. Methods: This analysis includes an investigation (Autism Dataset 4 from the NIMH repository, n = 2890) and a replication (Autism Dataset 3 from the NIMH repository, n = 1233) of trio samples with GWAS data. In Phase 1, a molecular pathway analysis is conducted on the investigation sample to test for the enrichment of specific Gene Ontology (GO) terms associated with autism. In Phase 2, the identified pathways are tested for enrichment in the replication sample. Permutation tests are performed to reduce the risk of false-positive findings. Quality assessment is conducted using QQ-plots and λ values, with Plink and R utilized for the Transmission Disequilibrium Test (TDT) and permutation tests. Results: The GO term GO:0007417 was found to be enriched in both the investigation and replication samples. SNPs associated with this pathway were observed at a frequency higher than expected in the replication sample. Conclusions: The GO term GO:0007417 (development of the nervous system) was associated with autism in both trio samples. Variations in the genes TMPRSS4, TRPC4, and PCDH9 were consistently linked to autism across the two independent samples, highlighting the role of calcium signaling and cell adhesion molecules in the risk of autism-related disorders. The pathways and variations associated with autism are described in detail, which can contribute to the engineering of new pharmacological treatments for ASD.

The irreversible, towards fatalic neuropathy: from the genesis of diabetes.

Diabetic neuropathy is the most prevalent diabetes-associated complication that negatively impacts the quality of life of the patients. The extensive complications of diabetic peoples in the world are the leading cause of neuropathic pain, and over-activation of different biochemical signalling process induces the pathogenic progression and are also corresponding the epidemic painful symptom of diabetic neuropathy. The main prevalent abnormality is neuropathy, which further causing distal symmetric polyneuropathy and focal neuropathy. The exact pathological complication of diabetes associated neuropathic algesia is still unclear, but the alteration in micro-angiopathy associated nerve fibre loss, hyper polyol formation, MAPK signalling, WNT signalling, tau-derived insulin signalling processes are well known. Furthermore, the post-translational modification of different ion channels, oxidative and nitrosative stress, brain plasticity and microvascular changes can contributes the development of neuropathic pain. However, in the current review we discussed about these pathogenic development of neuropathic pain from the genesis of diabetes, and how diabetes affects the physiological and psychological health, and quality of life of the patients. Furthermore, the treatment of diabetic neuropathy with conventional monotherapy and emerging therapy are discussed. In addition, the treatment with phytochemical constituents their mechanisms and clinical evidences are also reported. The future investigation is required on pathological alteration occurs in neuropathic individuals, and on molecular mechanisms as well as the adverse effect of phytochemicals to determine all aspects of neuropathic algesia including effective treatments, which will prevents the sympathetic pain in patients.

Signalling overhead minimization aware handover execution using ensemble learning in next generation wireless networks

Upcoming smart intelligent heterogeneous wireless networks (HWNs) and their uses can greatly benefit from the merging of long-term evolution (LTE) sub-6 GHz along with millimeter wave (mmWave) frequencies by boosting the coverage, bandwidth, reliability, seamless connectivity, and high quality of service (QoS). Nevertheless, because of the inability of directed waves in terms of coverage, it is difficult to locate the appropriate mmWave remote radio units (RRUs). Therefore, it is crucial to lessen the burden of the handover signaling processes. In meeting research requirements this paper presents signaling overhead minimization aware handover execution (SOMAHE) model. The SOMAHE model first introduces a novel handover mechanism between LTE and mmWave is presented in this research, followed by a machine learning (ML)-based autonomous handover execution technique. To estimate the handover success rate, the model introduces a feature ensemble learning (FEL) model built using XGBoost (XGB) model that makes use of sampling windows channel data. To conclude, combining FEL into the SOMAHE model reduces signaling overhead while simultaneously increasing the handover success-rate. Experiment results with varying mobile terminals, demonstrate that the SOMAHE model significantly outperforms the existing standard deep q-networks (DQN)-based handover-execution method.

Polygenic and transcriptional risk scores identify chronic obstructive pulmonary disease subtypes in the COPDGene and ECLIPSE cohort studies

Genetic variants and gene expression predict risk of chronic obstructive pulmonary disease (COPD), but their effect on COPD heterogeneity is unclear. We aimed to define high-risk COPD subtypes using genetics (polygenic risk score, PRS) and blood gene expression (transcriptional risk score, TRS) and assess differences in clinical and molecular characteristics. We defined high-risk groups based on PRS and TRS quantiles by maximising differences in protein biomarkers in a COPDGene training set and identified these groups in COPDGene and ECLIPSE test sets. We tested multivariable associations of subgroups with clinical outcomes and compared protein-protein interaction networks and drug repurposing analyses between high-risk groups. We examined two high-risk omics-defined groups in non-overlapping test sets (n=1133 NHW COPDGene, n=299 African American (AA) COPDGene, n=468 ECLIPSE). We defined "high activity" (low PRS, high TRS) and "severe risk" (high PRS, high TRS) subgroups. Participants in both subgroups had lower body-mass index (BMI), lower lung function, and alterations in metabolic, growth, and immune signalling processes compared to a low-risk (low PRS, low TRS) subgroup. "High activity" but not "severe risk" participants had greater prospective FEV1 decline (COPDGene:-51mL/year; ECLIPSE:-40mL/year) and proteomic profiles were enriched in gene sets perturbed by treatment with 5-lipoxygenase inhibitors and angiotensin-converting enzyme (ACE) inhibitors. Concomitant use of polygenic and transcriptional risk scores identified clinical and molecular heterogeneity amongst high-risk individuals. Proteomic and drug repurposing analysis identified subtype-specific enrichment for therapies and suggest prior drug repurposing failures may be explained by patient selection. National Institutes of Health.

Photoaging Protective Effects of Quercitrin Isolated from ‘Green Ball’ Apple Peel

Premature skin aging, also known as photoaging, refers to the changes in the structure and function of the skin caused by chronic sun exposure. The ultraviolet radiation in sunlight is one of the key factors that cause photoaging. Thus, matrix metalloproteinases (MMPs), transforming growth factor beta-1 (TGFB1), and nuclear factor kappa B (NF-κB) signaling can be an effective therapeutic strategy for ultraviolet B (UVB) exposure. In this study, we used human dermal fibroblast and mouse macrophage cells to identify the mediators of skin photoaging. Quercitrin isolated from ‘Green Ball’ apple peel was treated to UVB-irradiated fibroblast cells and lipopolysaccharide (LPS)-induced macrophages to identify the photoaging prevention effect of quercitrin. Genes that are associated with photoaging were determined by using enzyme-linked immunosorbent assay (ELISA), Western blot, and quantitative polymerase chain reaction (qPCR). Quercitrin increased the collagen biosynthesis in UVB-irradiated fibroblast cells via regulating MMPs, TIMP metallopeptidase inhibitor 1 (TIMP-1), TGFB1, hyaluronan synthase 2 (HAS2), and collagen type I alpha 1 chain (COL1A2). In addition, quercitrin regulated p-65, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), and its mediators (prostaglandin E2 and nitric oxide), in the NF-κB signaling process, and it inhibited the production of cytokines in LPS-induced macrophages. These results indicate that quercitrin can improve photoaging damaged skin by regulating MMPs, TGFB1, and NF-κB signaling pathway modulators.

The Parkinson’s disease risk gene cathepsin B promotes fibrillar alpha-synuclein clearance, lysosomal function and glucocerebrosidase activity in dopaminergic neurons

BackgroundVariants in the CTSB gene encoding the lysosomal hydrolase cathepsin B (catB) are associated with increased risk of Parkinson’s disease (PD). However, neither the specific CTSB variants driving these associations nor the functional pathways that link catB to PD pathogenesis have been characterized. CatB activity contributes to lysosomal protein degradation and regulates signaling processes involved in autophagy and lysosome biogenesis. Previous in vitro studies have found that catB can cleave monomeric and fibrillar alpha-synuclein, a key protein involved in the pathogenesis of PD that accumulates in the brains of PD patients. However, truncated synuclein isoforms generated by catB cleavage have an increased propensity to aggregate. Thus, catB activity could potentially contribute to lysosomal degradation and clearance of pathogenic alpha synuclein from the cell, but also has the potential of enhancing synuclein pathology by generating aggregation-prone truncations. Therefore, the mechanisms linking catB to PD pathophysiology remain to be clarified.MethodsHere, we conducted genetic analyses of the association between common and rare CTSB variants and risk of PD. We then used genetic and pharmacological approaches to manipulate catB expression and function in cell lines, induced pluripotent stem cell-derived dopaminergic neurons and midbrain organoids and assessed lysosomal activity and the handling of aggregated synuclein fibrils.ResultsWe find that catB inhibition impairs autophagy, reduces glucocerebrosidase (encoded by GBA1) activity, and leads to an accumulation of lysosomal content. In cell lines, reduction of CTSB gene expression impairs the degradation of pre-formed alpha-synuclein fibrils, whereas CTSB gene activation enhances fibril clearance. In midbrain organoids and dopaminergic neurons treated with alpha-synuclein fibrils, catB inhibition potentiates the formation of inclusions which stain positively for phosphorylated alpha-synuclein.ConclusionsThese results indicate that the reduction of catB function negatively impacts lysosomal pathways associated with PD pathogenesis, while conversely catB activation could promote the clearance of pathogenic alpha-synuclein.

Unraveling GPCRs Allosteric Modulation. Cannabinoid 1 Receptor as a Case Study.

G-protein-coupled receptors (GPCRs) constitute one of the most prominent families of integral membrane receptor proteins that mediate most transmembrane signaling processes. Malfunction of these signal transduction processes is one of the underlying causes of many human pathologies (Parkinson's, Huntington's, heart diseases, etc), provoking that GPCRs are the largest family of druggable proteins. However, these receptors have been targeted traditionally by orthosteric ligands, which usually causes side effects due to the simultaneous targeting of homologous receptor subtypes. Allosteric modulation offers a promising alternative approach to circumvent this problematic and, thus, comprehending its details is a most important task. Here we use the Cannabinoid type-1 receptor (CB1R) in trying to shed light on this issue, focusing on positive allosteric modulation. This is done by using the protein-dipole Langevin-dipole (PDLD) within the linear response approximation (LRA) framework (PDLD/S-2000) along with our coarse-grained (CG) model of membrane proteins to evaluate the dissociation constants (KBs) and cooperativity factors (αs) for a diverse series of CB1R positive allosteric modulators belonging to the 2-phenylindole structural class, considering CP55940 as an agonist. The agreement with the experimental data evinces that significantly populated allosteric modulator:CB1R and allosteric modulator:CP55940:CB1R complexes have been identified and characterized successfully. Analyzing them, it has been determined that CB1R positive allosteric modulation lies in an outwards displacement of transmembrane α helix (TM) 4 extracellular end and in the regulation of the range of motion of a compound TM7 movement for binary and ternary complexes, respectively. In this respect, we achieved a better comprehension of the molecular architecture of CB1R positive allosteric site, identifying Lys1923.28 and Gly1943.30 as key residues regarding electrostatic interactions inside this cavity, and to rationalize (at both structural and molecular level) the exhibited stereoselectivity in relation to positive allosteric modulation activity by considered CB1R allosteric modulators. Additionally, putative/postulated allosteric binding sites have been screened successfully, identifying the real CB1R positive allosteric site, and most structure-activity relationship (SAR) studies of CB1R 2-phenylindole allosteric modulators have been rationalized. All these findings point out towards the predictive value of the methodology used in the current work, which can be applied to other biophysical systems of interest. The results presented in this study contribute significantly to understand GPCRs allosteric modulation and, hopefully, will encourage a more thorough exploration of the topic.

Wnt7a-positive dendritic cytonemes control synaptogenesis in cortical neurons.

Synaptogenesis involves the transformation of dendritic filopodial contacts into stable connections with the exact apposition of synaptic components. Signalling triggered by Wnt/β-catenin and calcium has been postulated to aid this process. However, it is unclear how such a signalling process orchestrates synapse formation to organise the spatial arrangement of synapses along dendrites. We show that Wnt7a is loaded on dynamic dendritic filopodia during spine formation in human cortical neurons. Wnt7a is present at the tips of the filopodia and the contact sites with dendrites of neighbouring neurons, triggering spatially restricted localisation of the Wnt co-receptor Lrp6. Here, we find the induction of calcium transients, the clustering of pre- and postsynaptic proteins, and the subsequent transformation into mature spines. Although soluble Wnt7a protein can also support synaptogenesis, it fails to provide this degree of spatial information for spine formation and calcium transients and synaptic markers are induced ectopically along the dendrites. Our data suggest that dendritic filopodia are Wnt7a-bearing cytonemes required for focal calcium signalling, initiate synapse formation, and provide an elegant mechanism for orchestrating the positioning of synapses along dendrites.

Comprehensive analysis identifies endocrine fibroblast growth factors as promising prognostic markers for colorectal carcinoma

Endocrine fibroblast growth factors (eFGFs) play essential roles in cellular signaling processes, including development and differentiation, and are implicated in various cancers. However, their precise involvement in colon neoplasia and colon adenocarcinoma (COAD) remains incompletely understood. Here, we conducted a comprehensive investigation utilizing multiple databases to explore the multifaceted characteristics of eFGFs. Through integrated analyses of diverse databases, including TIMER2.0, UALCAN, OncoDB, cBioPortal, LinkedOmics, STRING, htfTarget, mirTarBase, circBank, and DGIdb, we explored eFGFs’ gene expression, DNA methylation, prognostic significance, genetic alterations, gene regulatory networks, functional analysis, and drug interactions in COAD patients. Our findings revealed elevated expression levels of eFGFs in COAD, with aberrant gene expression potentially linked to promoter methylation. Importantly, hypermethylation of FGF21 and FGF23 and downregulation of FGF23 correlated with poor survival outcomes in COAD patients. Functional analyses highlighted the involvement of eFGF genes in Ras signaling, PI3K-Akt signaling, and cancer pathways. Furthermore, we validated our findings through a cross-sectional study by quantitative real-time polymerase chain reaction (qRT-PCR), confirming significant overexpression of FGF21 in colon polyps compared to normal mucosa. Additionally, we observed elevated RNA expression of FGF21 and FGF23 in adenomatous polyps compared to hyperplastic polyps. This study sheds new light on the critical roles of eFGFs in COAD tumorigenesis and underscores their potential as promising prognostic markers for COAD, as well as discriminative markers for distinguishing high-risk from low-risk polyps. These findings provide valuable insights into the complex molecular mechanisms underlying colorectal neoplasia and offer potential avenues for targeted therapeutic strategies.

Metabolomics and dual proteomics identify contrasting patterns of major pathways affected in asparagus shoot upon Fusarium infection

Abstract Aims Infections with soil-borne pathogens have considerable detrimental effects on asparagus (Asparagus officinalis) growth and production, notably caused by the Fusarium species F. oxysporum f.sp. asparagi, F. proliferatum, and F. redolens. To get insight into the systemic effects of fungal infection on plant physiology to identify candidate resistance traits, we investigated this interaction using a multi omics approach. Methods Asparagus plants were inoculated with one of the three Fusarium species. After 8 weeks, basal stem parts were harvested and subjected to metabolome and proteome analysis as well as detection of fungal DNA. Results Upon infection, the pathogen spreads systemically from the root to the shoot and, consequently, fungal DNA and mycotoxins were detected in the basal part of the plant stem. Metabolite data revealed that the main pathway affected by Fusarium infections was “Fatty acids”, specifically the superclasses “Glycerophospholipids”, “Glycerolipids” and “Sphingolipids” being lower abundant upon infection. Another main pathway identified in the analysis was “Shikimates and Phenylpropanoids” with compounds assigned to these classes being mainly enriched upon infection. Proteome data revealed an induction of pathogen-defense proteins upon infection in asparagus, while proteins involved in vesicle trafficking and lipid metabolism were lower abundant. Conclusions This indicates that not only lipid-based signaling processes are distorted by Fusarium, but also fundamental processes such as vesicle formation, membrane integrity and cell wall organization. In planta proteome analysis of F. oxysporum led to the identification of 1,488 fungal proteins, including proteins involved in metabolic and cellular processes as well as putative virulence factors.

PhosX: data-driven kinase activity inference from phosphoproteomics experiments.

The inference of kinase activity from phosphoproteomics data can point to causal mechanisms driving signalling processes and potential drug targets. Identifying the kinases whose change in activity explains the observed phosphorylation profiles, however, remains challenging, and constrained by the manually curated knowledge of kinase-substrate associations. Recently, experimentally determined substrate sequence specificities of human kinases have become available, but robust methods to exploit this new data for kinase activity inference are still missing. We present PhosX, a method to estimate differential kinase activity from phosphoproteomics data that combines state-of-the art statistics in enrichment analysis with kinases' substrate sequence specificity information. Using a large phosphoproteomics dataset with known differentially regulated kinases we show that our method identifies upregulated and downregulated kinases by only relying on the input phosphopeptides' sequences and intensity changes. We find that PhosX outperforms the currently available approach for the same task, and performs better or similarly to state-of-the-art methods that rely on previously known kinase-substrate associations. We therefore recommend its use for data-driven kinase activity inference. PhosX is implemented in Python, open-source under the Apache-2.0 licence, and distributed on the Python Package Index. The code is available on GitHub (https://github.com/alussana/phosx). Supplementary data are available at Bioinformatics online.

Dynamic modelling of signalling pathways when ordinary differential equations are not feasible.

Mathematical modelling plays a crucial role in understanding inter- and intracellular signalling processes. Currently, ordinary differential equations (ODEs) are the predominant approach in systems biology for modelling such pathways. While ODE models offer mechanistic interpretability, they also suffer from limitations, including the need to consider all relevant compounds, resulting in large models difficult to handle numerically and requiring extensive data. In previous work, we introduced the retarded transient function (RTF) as an alternative method for modelling temporal responses of signalling pathways. Here, we extend the RTF approach to integrate concentration or dose-dependencies into the modelling of dynamics. With this advancement, RTF modelling now fully encompasses the application range of ODE models, which comprises predictions in both time and concentration domains. Moreover, characterizing dose-dependencies provides an intuitive way to investigate and characterize signalling differences between biological conditions or cell types based on their response to stimulating inputs. To demonstrate the applicability of our extended approach, we employ data from time- and dose-dependent inflammasome activation in bone marrow-derived macrophages treated with nigericin sodium salt. Our results show the effectiveness of the extended RTF approach as a generic framework for modelling dose-dependent kinetics in cellular signalling. The approach results in intuitively interpretable parameters that describe signal dynamics and enables predictive modelling of time- and dose-dependencies even if only individual cellular components are quantified. The presented approach is available within the MATLAB-based Data2Dynamics modelling toolbox at https://github.com/Data2Dynamics and https://zenodo.org/records/14008247 and as R code at https://github.com/kreutz-lab/RTF.

Alterations in the Levels of Urinary Exosomal MicroRNA-183-5p and MicroRNA-125a-5p in Individuals with Type 2 Diabetes Mellitus.

Background: Type 2 diabetes mellitus (T2DM) is a metabolic disorder, and urinary exosomal microRNAs (miRNAs) were utilized as potential disease prediction or diagnostic biomarkers in numerous studies. This study investigated the differential expression of urinary exosomal miRNAs between non-diabetes mellitus (NDM) individuals and those with T2DM. Aim: To elucidate the association between urinary exosomal miRNAs and T2DM. Methods: We recruited patients diagnosed with T2DM and NDM individuals in West China Hospital, Sichuan University, from November 2023 to February 2024. Subsequently, we performed sequencing of urinary exosomal microRNAs in both groups. The obtained sequencing results were further validated using RT-qPCR in both the training set and the validation set. Additionally, we conducted logistic regression analysis and Spearman correlation analysis on miRNAs with significant differential expression, as well as analysis of their biological functions. Results: A total of 118 urine samples were collected, 59 from individuals diagnosed with T2DM and 59 from NDM. There were differentially expressed miR-183-5p (p = 0.034) and miR-125a-5p (p = 0.008) between the two groups. Furthermore, multivariate regression analysis demonstrated that higher miR-125a-5p levels were negatively associated with the risk of T2DM (p = 0.044; OR: 0.046; 95% CI: 0.002, 0.922). Bioinformatics analysis indicated that the target genes of miR-183-5p were predominantly involved in insulin signaling and glucose transport processes, while those target genes of miR-125a-5p primarily mediated autophagy. Conclusions: miR-183-5p and miR-125a-5p might be involved in the pathogenesis of T2DM, while higher urinary exosomal miR-125a-5p was negatively associated with the risk of T2DM.

DbPTM 2025 update: comprehensive integration of PTMs and proteomic data for advanced insights into cancer research.

Post-translational modifications (PTMs) are essential for modulating protein function and influencing stability, activity and signaling processes. The dbPTM 2025 update significantly expands the database to include over 2.79 million PTM sites, of which 2.243 million are experimentally validated from 48 databases and over 80 000 research articles. This version integrates proteomic data from 13 cancer types, with a particular focus on phosphoproteomic data and kinase activity profiles, allowing the exploration of personalized phosphorylation patterns in tumor samples. Integrating kinase-substrate phosphorylations with E3 ligase-substrate interactions, dbPTM 2025 provides a detailed map of PTM regulatory networks, offering insights into cancer-specific post-translational regulations. This update also includes advanced search capabilities, enabling users to efficiently query PTM data across species, PTM typesand modified residues. The platform's new features-interactive visualization tools and streamlined data downloads-allow researchers to access and analyze PTM data easily. dbPTM 2025 also enhances functional annotations, regulatory networks and disease associations, broadening its application for cancer research and the study of disease-associated PTMs. Through these enhancements, dbPTM 2025 is a comprehensive, user-friendly resource, facilitating the study of PTMs and their roles in cancer research. The database is now freely accessible at https://biomics.lab.nycu.edu.tw/dbPTM/.

Glyphosate contact alters the expression of genes in the head of africanized Apis mellifera bees

The increase in the world population results in a greater demand for food, intensifying the dependence on pesticides use. Glyphosate, a pesticide widely used in crops, can contaminate resources collected by bees. In this context, this study aimed to analyze the transcriptome of the head of Africanized Apis mellifera bees during the foraging phase to determine whether contact with the herbicide glyphosate, in lethal and sublethal doses, causes changes in the gene expression profile. For this, 180 marked bees were collected from their hives, aged 21 days, and distributed into three treatment groups: 1) bees in contact with the lethal dose of glyphosate (255.73 µg/bee); 2) bees in contact with the sublethal dose of glyphosate (2.5573 µg/bee); 3) control group with distilled water. Transcriptome analysis was performed on 12 bees from each treatment after one and four hours of exposure. The results show that one hour of contact with glyphosate resulted in 57 genes presenting differential expression in relation to the control (11 lethal and 53 sublethal), interfering in the signaling, communication and metabolism processes, while four hours of exposure, 38 genes (32 lethal and 11 sublethal) related, mainly, to the stimulation of the immune response. In summary, glyphosate affects the gene expression of honey bees during the foraging phase, at both doses, resulting in negative effects on behavior, metabolism and immune system, which compromises the health, activity and development of the colonies, also compromising the process of pollination.

EXTH-44. ENHANCING THERAPEUTIC APPROACHES IN HIGH-GRADE GLIOMAS: SYNERGISTIC EFFECTS OF LSD1 AND KINASE INHIBITION

Abstract BACKGROUND Glioblastoma (GBM) and Diffuse Intrinsic Pontine Glioma (DIPG) are devastating high-grade gliomas (HGGs) with poor prognoses. Lysine-specific demethylase 1 (LSD1) is a promising therapeutic target and a key regulator in tumor initiation and recurrence. Crosstalk between LSD1 and other signaling pathways, such as the MAPK pathway, frequently hyperactivated in HGG, offers an opportunity to enhance the efficacy of LSD1 inhibitors. This study investigates the combined inhibition of LSD1 and kinase signaling to improve therapeutic outcomes in HGG. METHODS Transcriptional changes following LSD1 knockdown in human GBM cells were analyzed using RNA-seq and GSEA. RPPA and western blotting assessed the impact of LSD1 inhibition on kinase signaling. Pharmacological LSD1 inhibition was tested using NCD38 or bomedemstat in HGG models and normal human astrocytes (NHA). The effects of combining LSD1 inhibitors with kinase inhibitors (osimertinib, afatinib, and ulixertinib) on cell viability were evaluated. Combination treatment was also assessed in orthotopic xenograft models of GBM. RESULTS GSEA revealed LSD1 expression was enriched for gene sets involved in kinase signaling processes. Increased phosphorylated ERK1/2 levels were observed following NCD38 treatment in MDA-GSC17, as shown by RPPA and western blot analyses. The LSD1 inhibitor, NCD38, increased phospho-ERK1/2 levels (72% increase from baseline), while co-treatment with osimertinib mitigated this effect. Combined LSD1 and kinase inhibition (EGFR and ERK inhibition) showed synergistic effects in vitro in GBM and DIPG models but not in the NHA. DISCUSSION Our results demonstrate that kinase activity can be modulated by inhibiting LSD1, potentially leading to a resistant subpopulation. This study underscores the potential of combining LSD1 and kinase inhibition to enhance therapeutic efficacy in HGG, including GBM and DIPG. Future research will focus on elucidating the mechanisms by which LSD1 regulates kinase signaling, aiming to optimize combination therapies.

Allosteric regulation of the tyrosine phosphatase PTP1B by a protein-protein interaction.

Protein-protein interactions are critical for cell signaling. The interaction between the phosphatase PTP1B and adaptor protein Grb2 co-localizes PTP1B with its substrates, thereby enhancing their dephosphorylation. We show that Grb2 binding also directly modulates PTP1B activity through an allosteric mechanism involving the proline-rich region of PTP1B. Our study reveals a novel mode of PTP1B regulation through a protein-protein interaction that is likely to be exploited by other cellular interactors of this important signaling enzyme.

Diatoms exhibit dynamic chloroplast calcium signals in response to high light and oxidative stress.

Diatoms are a group of silicified algae that play a major role in marine and freshwater ecosystems. Diatom chloroplasts were acquired by secondary endosymbiosis and exhibit important structural and functional differences from the primary plastids of land plants and green algae. Many functions of primary plastids, including photoacclimation and inorganic carbon acquisition, are regulated by calcium-dependent signalling processes. Calcium signalling has also been implicated in the photoprotective responses of diatoms; however, the nature of calcium elevations in diatom chloroplasts and their wider role in cell signalling remains unknown. Using genetically encoded calcium indicators, we find that the diatom Phaeodactylum tricornutum exhibits dynamic calcium elevations within the chloroplast stroma. Stromal calcium ([Ca2+]str) acts independently from the cytosol and is not elevated by stimuli that induce large cytosolic calcium ([Ca2+]cyt) elevations. In contrast, high light and exogenous hydrogen peroxide (H2O2) induce large, sustained [Ca2+]str elevations that are not replicated in the cytosol. Measurements using the fluorescent H2O2 sensor roGFP2-Oxidant Receptor Peroxidase 1 (Orp1) indicate that [Ca2+]str elevations induced by these stimuli correspond to the accumulation of H2O2 in the chloroplast. [Ca2+]str elevations were also induced by adding methyl viologen, which generates superoxide within the chloroplast, and by treatments that disrupt non-photochemical quenching (NPQ). The findings indicate that diatoms generate specific [Ca2+]str elevations in response to high light and oxidative stress that likely modulate the activity of calcium-sensitive components in photoprotection and other regulatory pathways.

Molecular pathology of skin fragility

The skin's barrier function is primarily maintained by the cohesion of its layers and the specialized stratum corneum. Genetic and autoimmune disorders that result in skin fragility have significantly contributed to understanding the role of various molecular components in the skin. These conditions, characterized by blisters, erosions, wounds, and impaired wound healing, are rare but must be considered in clinical differential diagnoses. Key cutaneous adhesion structures include the epidermal basement membrane, anchoring fibrils, cell-matrix adhesions (e.g., hemidesmosomes and focal adhesions), and cell-cell adhesions (e.g., desmosomes and corneodesmosomes). These multiprotein suprastructures not only provide structural support but also participate in signaling processes and physiological or pathological conditions such as skin aging and wound healing. Additionally, dermal connective tissue plays astructural role and serves as areservoir for proteases, growth factors, and cytokines. Modern techniques like single-cell and spatial transcriptomics, combined with artificial intelligence algorithms, are advancing the molecular mapping of human skin. Moreover, this review highlights the molecular composition of adhesion structures and the specific diseases associated with deficiencies in these components.

ROS as Signaling Molecules to Initiate the Process of Plant Acclimatization to Abiotic Stress.

During their life cycle, plants constantly respond to environmental changes. Abiotic stressors affect the photosynthetic and respiratory processes of plants. Reactive oxygen species (ROS) are produced during aerobic metabolism and play an important role as regulatory mediators in signaling processes, activating the plant's protective response to abiotic stress and restoring "oxidation-reduction homeostasis". Cells develop normally if the rates of ROS production and the ability to neutralize them are balanced. To implement oxidation-reduction signaling, this balance must be disrupted either by an increase in ROS concentration or a decrease in the activity of one or more antioxidant systems. Under abiotic stress, plants accumulate excessive amounts of ROS, and if the ROS content exceeds the threshold amount dangerous for living organisms, it can lead to damage to all major cellular components. Adaptive resistance of plants to abiotic stressors depends on a set of mechanisms of adaptation to them. The accumulation of ROS in the cell depends on the type of abiotic stress, the strength of its impact on the plant, the duration of its impact, and the recovery period. The aim of this review is to provide a general understanding of the processes occurring during ROS homeostasis in plants, oxidation-reduction processes in cellular compartments in response to abiotic stress, and the participation of ROS in signaling processes activating adaptation processes to abiotic stress.