Biology subjects

Diaz, A.

Publications and source records attributed to Diaz, A..

At least 19 recordsLinked to original sources

bioRxiv2026

Avian uropygial secretions as a novel bioinsecticide for mosquito vector control

Background: Malaria control relies heavily on interventions targeting mosquito vectors, but the rapid emergence of insecticide resistance threatens the effectiveness of existing approaches. Identifying novel, effective, and environmentally sustainable insecticides is therefore a priority. Birds produce uropygial secretions with well-documented antimicrobial properties, but their potential insecticidal activity against mosquitoes, including malaria vectors, remains unexplored. Methods: We evaluated the insecticidal activity of uropygial secretions from wild house sparrows (Passer domesticus) against the malaria vector Anopheles stephensi and four additional mosquito species of medical importance (Aedes aegypti, Aedes albopictus, Culex pipiens, and Culiseta longiareolata). A total of 2,293 adult mosquitoes were tested using CDC bottle bioassays at three secretion concentrations (0.5, 0.25, and 0.125) and an untreated control. Mosquito mortality was monitored for 120 min. Results: Uropygial secretions caused substantial mosquito knockdown/mortality, with effects increasing with concentration and exposure time. Susceptibility differed significantly among species after 120 min. Notably, An. stephensi was particularly susceptible, reaching knockdown/mortality of 92%, 94%, and 83% at 0.5, 0.25, and 0.125 concentrations, respectively. Conclusions: Our findings provide the first experimental evidence that avian uropygial secretions possess direct insecticidal activity against mosquitoes and identify them as a previously overlooked source of naturally derived insecticidal compounds. The high susceptibility of An. stephensi highlights their potential relevance for developing novel bioinsecticides for malaria vector control.

ecology↗

bioRxiv2026

Scop3P-Toolkit: executable structure-aware workflows linking PTMs, peptides, and mutations to protein function

Post-translational modifications (PTMs) and genetic variants regulate protein function, signalling, and disease, but their interpretation requires integration of sequence annotations with structural, interaction, and biophysical context. Although resources such as Scop3P, UniProt, the Protein Data Bank, and AlphaFold provide extensive annotations and structural information, integrating these data into reproducible structure-aware analyses still requires custom scripting and manual coordination between multiple independent tools. To address this challenge, we developed Scop3P-Toolkit, an open-source executable analytical environment for interactive analysis of PTMs, mutations, and proteomics-derived peptides in their structural context. The toolkit integrates protein annotation retrieval with structural mapping, residue interaction network analysis, comparative structural analysis, and residue-level biophysical profiling within a unified framework. Experimentally supported phosphosites, phosphopeptides, and phosphoproteomics evidence are provided for human proteins through Scop3P, with optional integration of curated UniProt PTM annotations. UniProt-derived PTMs, sequence features, and genetic variants are available for proteins from any species, extending the framework beyond the human phosphoproteome. Scop3P-Toolkit supports structure-centric analyses including interpretation of PTMs and disease-associated variants, analysis of residue interaction networks and their rewiring across alternative conformations, structural localisation of peptides, and exploration of protein-protein, protein-ligand, and host-pathogen interfaces. Interactive visualisation links sequence annotations, three-dimensional structures, residue interaction networks, and biophysical profiles, enabling coordinated exploration across multiple molecular representations. The toolkit is distributed as Jupyter notebooks, browser-based Voila applications, and a Galaxy interactive tool, providing transparent, accessible, and reproducible workflows for both computational and experimental researchers. By integrating biological annotation resources into executable, structure-aware workflows, Scop3P-Toolkit enables reproducible interpretation of PTMs, mutations, and proteomics data.

bioinformatics↗

bioRxiv2026

Scop3P in 2026: an expanded proteomics-informed resource contextualizing phosphorylation sites through sequence, structure, mutation, and experimental provenance

Protein phosphorylation is a central regulatory mechanism controlling protein activity, interactions, and cellular signalling, and its dysregulation is implicated in numerous diseases. Advances in mass spectrometry-based phosphoproteomics have led to a rapid expansion in the number of reported phosphorylation sites; however, interpretation of these data remains challenging due to fragmented evidence, limited structural context, and the lack of uniform experimental provenance across resources. Interpretation is further complicated by the fact that the biological meaning of reported phosphosites can vary substantially across tissues, cell lines, perturbations, and disease settings. Here, we present a major update of Scop3P, a proteomics-informed knowledgebase that contextualizes human phosphorylation sites within integrated sequence, structural, biophysical, evolutionary, and mutational frameworks. The current release incorporates uniformly reprocessed human phosphoproteomics data from 116 PRIDE datasets alongside curated UniProt annotations, retaining peptide-spectrum matches, site localization confidence, and direct links to primary mass spectrometry evidence via Universal Spectrum Identifiers. This integration yields 152,350 unique serine, threonine, and tyrosine phosphorylation sites across 16,533 human proteins, supported by full experimental provenance. Beyond site identification, Scop3P provides residue-level contextual annotations derived from experimentally determined protein structures and proteome-wide AlphaFold models, enabling near-complete structural coverage of phosphorylation sites. Structural context is further complemented by residue-level biophysical, evolutionary, and mutational annotations, supporting integrated assessment of phosphorylation in functional and disease-related settings. The current release also introduces residue interaction network representations derived from AlphaFold-predicted structures, capturing spatial connectivity and local interaction environments of phosphorylation and mutation sites. A redesigned web interface enables interactive exploration through coordinated 1D, 2D, 2.5D, and 3D visualizations, peptide-level coverage views, and direct access to original spectra via PRIDE. By bridging experimental phosphoproteomics with structural, functional, and disease-related context, Scop3P provides a scalable and provenance-aware resource for phosphosite interpretation, hypothesis generation, and data-driven modelling of phosphorylation-dependent regulation.

bioinformatics↗

bioRxiv2026

USP7 maintains hematopoietic stem cell dormancy and function by stabilizing HMGA2

Hematopoietic stem cell (HSC) longevity critically depends on maintaining a deep dormant state, yet the molecular mechanisms that preserve this rare and functionally essential population remain poorly understood. Here, we identify the deubiquitinase USP7 as a key regulator of long-term HSC dormancy. Using a Usp7+/- mouse model, we uncover selective depletion of hematopoietic stem and progenitor cells (HSPCs), which is associated with impaired long-term repopulation capacity. Strikingly, H2B-GFP label-retention assays reveal a profound loss of dormant HSCs in Usp7+/- mice, demonstrating a failure to maintain the most quiescent stem cell fraction in vivo. Consistently, single-cell RNA sequencing shows erosion of the transcriptional dormancy program, linking USP7 activity to the preservation of stem cell identity at both functional and molecular levels. Mechanistically, ultra-low-input proteomic profiling and biochemical approaches identify HMGA2 as a novel USP7 substrate, suggesting that ubiquitin-dependent regulation of chromatin architecture contributes to the control of HSC dormancy. Together, our findings establish USP7 as a critical regulator of HSC dormancy, revealing a previously unrecognized post-translational mechanism controlling stem cell longevity, with implications for aging, regeneration, and hematopoietic disorders.

cell biology↗

bioRxiv2026

Classification of image category based on spatially distributed, transient high-frequency events

Transient high-frequency activity (HFA) in local field potentials exhibits substantial variability across trials and behavioral states, yet its functional role in sensory representation remains poorly understood. Here, we tested whether transient HFA events carry stimulus-related information through their temporal, spectral, and phase-dependent properties. Using intracranial recordings from 21 human participants performing a visual localizer task, we extracted transient HFA events and quantified their features using information-theoretic and decoding analyses. Individual event features carried only modest information about stimulus identity, and response magnitude and morphology-related properties contributed minimally to decoding performance. Instead, decoding was dominated by temporal alignment and low-frequency phase. Critically, representing transient events as distributed low-frequency phase configurations across electrodes substantially improved cross-trial decoding performance, whereas disrupting distributed phase structure eliminated this decoding advantage. These findings indicate that stimulus-related structure in transient HFA does not primarily arise from isolated local event properties, but instead emerges through distributed, phase-dependent network dynamics. More broadly, the results provide a framework for understanding how transient high-frequency neural activity contributes to sensory representations across distributed cortical networks.

neuroscience↗

bioRxiv2025

Specifind: A Natural Language Processing Tool for Automating Species Occurrence (Re-)Discovery from Scientific Literature

A vast amount of valuable information on species occurrences remains embedded within the unstructured and continuously expanding body of ecological literature written in natural language. When effectively extracted, such dispersed knowledge has the potential to significantly improve understanding of species distributions and ecological patterns, thereby enabling more targeted and informed conservation actions. To address this challenge, Specifind is introduced as a tool designed to facilitate the extraction of species occurrence data through the identification of scientific species names, geographic references, and the relationships between them while ensuring traceability. At its core lies a newly developed and expertly annotated dataset comprising over one thousand open-access abstracts drawn from five domains: biogeography, botany, entomology, mycology, and zoology. A suite of Natural Language Processing components has been integrated, including Document Layout Analysis, Optical Character Recognition, Named Entity Recognition, Coreference Resolution, and Relation Extraction. These components enable the accurate identification and contextual linking of species and geographic entities, even when references are distributed throughout the text. As a result, Specifind enhances the discoverability and usability of species occurrence information embedded within unstructured scientific texts. It is expected to reduce the substantial effort required for manual literature review, thereby supporting biodiversity research, informing conservation planning, and facilitating ecological analysis.

bioinformatics↗

bioRxiv2025

Functional Characterization of 123 Genes from Mycobacteriophage LeBron Uncovers Cytotoxic Gene Families in Cluster L1

Bacteriophages represent a vast reservoir of genetic diversity however, functional annotation remains a major challenge, as most predicted gene products lack detectable similarity to characterized gene families. Experimental approaches such as systematic overexpression screens provide an avenue for identifying phage genes that influence bacterial physiology. Here, we report an overexpression screen of all 123 predicted protein-coding genes from Cluster L1 mycobacteriophage LeBron, the first representative of this cluster to undergo genome-wide functional analysis. Expression assays in Mycobacterium smegmatis revealed that 39 genes (32%) impaired host growth, with nineteen of these toxic genes (49%) assigned no known function. The proportion of cytotoxic genes observed in LeBron is comparable to findings from Clusters K and F, despite minimal sequence conservation across clusters. Interestingly, a subset of LeBrons toxic genes appear to be functionally analogous to previously identified toxic genes in other clusters, suggesting conserved biological activities carried out by non-homologous proteins. Additionally, this analysis uncovered several novel gene families that elicit strong cytotoxic effects, expanding the known catalog of phage-derived bacterial growth inhibitors. These results provide new insights into phage gene functions and demonstrate the value of genome-wide expression screening for uncovering conserved and cluster-specific interactions between bacteriophages and their hosts.

microbiology↗

bioRxiv2025

Integrated environmental drivers and evolutionary history reveal conserved patterns of avian exposure to West Nile and Saint Louis encephalitis viruses

The increasing threat of emerging vector-borne diseases, affecting both humans and wildlife, necessitates a nuanced understanding of the complex interactions among vectors, hosts, and pathogens. Focusing on West Nile Virus (WNV) and Saint Louis encephalitis Virus (SLEV) activity in avian communities of central and northern Argentina, this study delves into the intricate dynamics of exposure risk employing phylogenetic mixed models. Contrary to expectations, ecological traits displayed negligible influence on exposure risk. Instead, temperature seasonality and altitude, emerged as crucial predictors. The phylogenetic signal indicated a conserved susceptibility along the avian evolutionary tree, with Furnariidae, Turdidae and Columbidae families exhibiting higher exposure risk. These findings challenge prevailing notions about the dominant role of ecological traits in mosquito-borne pathogens. The study underscores the need for a holistic understanding, emphasizing the intricate interplay of environmental, phylogenetic, and ecological elements in shaping avian exposure to WNV and SLEV, offering vital insights for future research and public health strategies.

ecology↗

bioRxiv2025

Radiation dose effects in correlative X-ray / cryo-electron microscopy of frozen hydrated biological samples

In cryo-electron microscopy (cryo-EM), imaging of biological specimens is restricted by the limited field of view and by sample thickness. Hard X-ray imaging, with its ability to penetrate samples several tens of micrometers thick, offers a complementary approach for high-resolution visualization. A major concern is whether cryo-preserved samples can withstand the handling conditions at synchrotron facilities without excessive icing, and whether the radiation exposure during X-ray imaging compromises specimen integrity, thereby hindering subsequent attempts to achieve high-resolution 3D reconstructions via cryo-EM. To evaluate this, we deposited apoferritin samples on a cryo-EM grid, exposed them to varied X-ray doses typical for X-ray tomography experiments at a synchrotron facility, and subsequently analysed the exposed particles by cryo-EM. Despite the apparent damage sustained throughout the experiment, the samples remained amenable to cryo-EM analysis, with structural details at a resolution of [~]4 [A] at the highest absorbed X-ray dose of 100 MGy. By comparison, a similar cryo-EM dataset of the apoferritin particles that were not exposed to X-rays but were mounted on the same cryo-EM grid, resulted in a 3D reconstruction at 3.17 [A] resolution. Thus, while radiation damage may limit the high-resolution information in specimens processed by cryo-X-ray tomography, the cryo-preserved biological material exposed to these high X-ray doses can be still used for subsequent cryo-EM workflows aiming to obtain structural biology insights at intermediate to high resolution. These findings lay the groundwork for an integrated imaging workflow that combines X-ray and cryo-EM techniques to enable multiscale analysis of thick vitrified biological specimens.

biophysics↗

bioRxiv2025

On the possible inhibition of macrophage inflammatory responses by phytic acid produced by Echinococcus multilocularis

Echinococcus multilocularis, causing agent of alveolar echinococcosis, down-regulates host immunity 1,2. Salzmann et al showed that macrophages close to the parasite produce little IL-6 and the parasite extract mimics this inhibition in cultured macrophages 3. The authors then showed that E. multilocularis contains phytic acid and that commercial phytic acid inhibits cytokine responses in stimulated macrophages. Through comparison with effects of EDTA and intracellular calcium measurements, they concluded that phytic acid inhibits macrophage responses through calcium depletion, extrapolating this conclusion to assays with parasite extract and infection setting. However, the interaction between phytic acid and calcium is complex 4,5. Calcium is indeed depleted in the assays with commercial phytic acid according to our quantitative predictions. However additional changes occur including formation of solid calcium phytate, which probably moderates the inhibition of responses observed under calcium depletion. We calculate that in the experiments with parasite extract, phytic acid present cannot deplete calcium and therefore inhibition must be driven by a different mechanism, possibly independent of phytic acid. Further, we argue that calcium depletion is an unlikely in vivo immune regulatory mechanism. We propose that biological assays using calcium phytate are needed for ascertaining whether phytic acid has biologically relevant anti-inflammatory activity.

immunology↗

bioRxiv2025

Going green: Recycling transcriptomes to infer evolutionary relationships, gene duplication, gene tree conflict, and patterns of molecular evolution in the Apocynaceae

Background and AimsThe flowering plant family Apocynaceae exhibits diverse adaptations with biological and pharmaceutical significance, many of which have been studied with RNA-seq. However, despite the available transcriptomic data, no focused phylotranscriptomic study has been conducted to characterize the patterns of molecular evolution in this group. In this study, we leverage a dataset composed predominately of publicly available transcriptomes to infer relationships within Apocynaceae and explore the molecular processes that have shaped their divergences. MethodsWe extracted nuclear, chloroplast, and mitochondrial genes from 47 publicly available and one newly sequenced transcriptome to assemble and infer species relationships across Apocynaceae. Leveraging the gene-rich nuclear phylotranscriptomic data, we inferred molecular dates and investigated the complex history of gene tree conflict, molecular rate shifts, and gene duplications. To investigate the genomic basis of adaptations, we analyzed the inferred 14,838 gene duplications at the base of Apocynaceae for shared functional enrichment of genes related to evolutionary innovations. Key ResultsThe Apocynaceae topology inferred from our phylotranscriptomic analysis is highly concordant with the current consensus. Notably, a genome-wide acceleration in molecular rate subtends the Ceropegieae tribe. We observed that a decreased time between divergences is associated with a higher rate of gene tree conflict, a pattern especially prevalent across the Apocynaceaes historically recalcitrant backbone relationships. Furthermore, gene duplications may underlie evolutionary innovations, such as immunity-related gene expansion in the genus Asclepias and duplications associated with trichome modifications in the epiphytic Hoya. Finally, we discuss the contentious history of whole-genome duplication (WGD) within the Apocynaceae and emphasize the need for further investigation into the placement of WGDs. ConclusionsRepurposing transcriptomes is a powerful means of accumulating data for novel insights in plant evolution, especially during uncertain funding and cases where budget restrictions exist. Leveraging this gene-dense dataset, we obtained novel insights into the molecular evolution of Apocynaceae and identified areas for future investigations.

evolutionary biology↗

bioRxiv2025

Developmental Plasticity and Stromal Co-option Shape a Pituitary Neuroendocrine Tumor Transcriptional Continuum

Pituitary neuroendocrine tumors (PitNETs) are common intracranial neoplasms with complex biology underpinned by unresolved cellular origins, molecular heterogeneity, and microenvironment interactions. Here, we employ single-nuclei RNA-sequencing (snRNA-seq) of 419,874 cells from human normal pituitaries and PitNETs with spatial transcriptomics to resolve these challenges. We identify multi-hormonal neuroendocrine cells in both normal and tumor tissues, originating as early pseudotime intermediates from pituitary stem cells, revealing an inherent plasticity that blurs traditional lineage boundaries. PitNETs exhibit a transcriptional continuum across subtypes, challenging their classification into discrete categories. Trajectory analysis uncovers divergent cellular origins: silent gonadotroph adenomas (SGAs), prolactinomas, silent corticotroph adenomas (SCAs), and Cushings adenomas are closely linked to differentiated neuroendocrine cells, while somatotroph and null cell adenomas (NCAs) appear to derive more directly from adult stem cells. Tumor cells co-opt robust cell-cell communication networks found in normal adult neuroendocrine cells. Spatial profiling further demonstrates that perivascular niches enhance tumorigenicity through angiogenic and epithelial-mesenchymal transition programs. Our work redefines PitNETs as ecosystems shaped by developmental plasticity and microenvironmental crosstalk, offering a roadmap for future therapies targeting lineage fluidity and stromal dependencies.

cancer biology↗

bioRxiv2025

Slow-Timescale Regulation of Dopamine Release and Mating Drive over Days

The rise and fall of motivational states may take place over timescales as long as many days. We used mouse mating behavior to model how the brain orchestrates slow-timescale changes in motivation. Male mice become sexually satiated after successful matings, and their motivation to mate gradually recovers over a week. Using deep-brain fluorescence-lifetime imaging in the medial preoptic area (MPOA), we found that tonic dopamine transmission--which regulates mating drive--also declined after mating and re-emerged over a week. Two mechanisms regulated dopamine transmission. First, successful mating transiently reduced tonic firing of hypothalamic dopamine-releasing neurons, thereby inhibiting dopamine release and mating behavior. Second, mating reduced the ability of these neurons to produce and release dopamine, and this ability gradually returned over the week-long recovery time course. Therefore, fast and slow mechanisms of neuronal plasticity cooperate to control the early and late phases of motivational dynamics, respectively.

neuroscience↗

bioRxiv2025

CLONEID: A Framework for Monitoring and Steering Subclonal Dynamics

Molecular assays can resolve clonal structure, but they are expensive and typically sparse in time, whereas phenotypic observations such as imaging can be collected frequently but often are not preserved in the context needed for later interpretation. We present CLONEID, an event-based framework for organizing clone-resolved phenotypic, molecular, and specimen-context records so that genotype-to-phenotype interpretation can be maintained across time. CLONEID links time-stamped Events, assay-specific Perspectives, and reconciled Identities through structured ingestion, provenance-aware retrieval, and reproducible export, complementing upstream clone-calling methods. In a long-term gastric cancer density-selection experiment, CLONEID linked repeated culture events, growth measurements, and late karyotypic profiling within a shared record, supporting longitudinal interpretation of phenotypic adaptation together with underlying chromosomal state.

bioinformatics↗

bioRxiv2025

Distribution patterns of aquatic birds in a high-Andean wetland in southeastern Peru: an approach based on environmental factors

High-Andean wetlands play a crucial role in the conservation of avian biodiversity, acting as ecological oases amidst the arid Andes. However, these ecosystems face increasing anthropogenic and climatic pressures, jeopardizing both the ecosystem services they provide and the biodiversity they harbor. Moreover, research on these ecosystems remains scarce, limiting the knowledge necessary for their effective conservation. This study, conducted in Lake Piuray in the southeastern Andes of Peru, investigated the spatial and temporal distribution patterns of aquatic birds, assessing the influence of environmental variables such as depth and chlorophyll-a content. From December 2022 to November 2023, monthly surveys were carried out at 13 counting points distributed across four zones of the lake, encompassing natural and altered habitats such as lakeshore beaches and cultivated areas. Distribution maps were generated using weighted interpolation models and additive models to analyze non-linear relationships between bird abundance and environmental variables. Additionally, differences between seasons (wet and dry) and the evaluated zones were analyzed using non-parametric tests. A total of 43 aquatic bird species were recorded, with 19,768 individuals. Areas with low depth (<15 m) and intermediate to high levels of chlorophyll-a (I543 index: 0.20-0.25) concentrated the highest abundance and species richness. Zones with lakeshore beaches showed greater abundance and richness, while deeper zones exhibited the lowest values. At the family level, shorebirds preferred shallow waters, and diving birds tolerated greater depths. Although no significant differences in richness, abundance, and diversity were found between seasons at the community level, differences were identified in six families, with variations in their abundance between the wet and dry seasons. These results highlight the importance of shallow areas with high chlorophyll-a concentrations for the conservation of aquatic birds in high-Andean wetlands. This study is one of the few to analyze the influence of environmental and temporal factors on the distribution of high-Andean aquatic birds, and its representative nature makes it a valuable model for identifying priority areas for the conservation of these species.

ecology↗

bioRxiv2024

GPCRchimeraDB: A database of chimeric G-Protein Coupled Receptors (GPCRs) to assist their design

G protein-coupled receptors (GPCRs) are membrane proteins crucial to numerous diseases, yet many remain poorly characterized and untargeted by drugs. Chimeric GPCRs have emerged as valuable tools for elucidating GPCR function by facilitating the identification of signaling pathways, resolving structures, and discovering novel ligands of poorly understood GPCRs. Such chimeric GPCRs are obtained by merging a well- and less-well-characterized GPCR at the intracellular limits of their transmembrane regions or intracellular loops, leveraging knowledge transfer from the well-characterized GPCR. However, despite the 212 chimeric GPCRs engineered to date, the design process remains largely trial-and-error and lacks a standardized approach. To address this gap, we introduce GPCRchimeraDB (https://www.bio2byte.be/gpcrchimeradb/), the first comprehensive database dedicated to chimeric GPCRs. It catalogs 212 chimeric receptors, identified through literature review, and includes 1,755 class A natural GPCRs, enabling connections between chimeras and their parent receptors while facilitating the exploration of novel parent combinations. Both chimeric and natural GPCR entries are extensively described at the sequence, structural, and biophysical level through a range of visualization tools, with annotations from resources like UniProt and GPCRdb and predictions from AlphaFold2 and b2btools. Additionally, GPCRchimeraDB offers a GPCR sequence aligner and a feature comparator to investigate differences between natural and chimeric receptors. It also provides design guidelines to support rational chimera engineering. GPCRchimeraDB is therefore a resource to facilitate and optimize the design of new chimeras, so helping to gain insights into poorly characterized receptors and contributing to advances in GPCR therapeutic development.

bioengineering↗

bioRxiv2024

An Exact and Fast SAT Formulation for the DCJ Distance

Reducing into a satisfiability (SAT) formulation has been proven effective in solving certain NP-hard problems. In this work, we extend this research by presenting a novel SAT formulation for computing the double-cut-and-join (DCJ) distance between two genomes with duplicate genes. The DCJ distance serves as a crucial metric in studying genome rearrangement. Previous work achieved an exact solution by transforming it into a maximum cycle decomposition (MCD) problem on the corresponding adjacency graph of two genomes, followed by reducing this problem into an integer linear programming (ILP) formulation. Using both simulated datasets and real genomic datasets, we firmly conclude that the SAT-based method scales much better and runs faster than using ILP, being able to solve a whole new range of instances which the ILP-based method cannot solve in a reasonable amount of time. This underscores the SAT-based approach as a versatile and more powerful alternative to ILP, with promising implications for broader applications in computational biology.

bioinformatics↗

bioRxiv2024

A Novel Human TBCK- Neuronal Cell Model Results in Severe Neurodegeneration and Partial Rescue with Mitochondrial Fission Inhibition

Background and ObjectivesTBCK syndrome is a rare fatal pediatric neurodegenerative disease caused by biallelic loss-of-function mutations in the TBCK gene. Previous studies by our lab and others have implicated mTOR, autophagy, lysosomes, and intracellular mRNA transport, however the exact primary pathologic mechanism is unknown. This gap has prevented the development of targeted therapies. MethodsWe employed a human neural progenitor cell line (NPC), ReNcell VM, which can differentiate into neurons and astrocytes, to understand the role of TBCK in mTORC1 activity and neuronal autophagy and cellular mechanisms of pathology. We used shRNA technology to knockdown TBCK in ReNcells. ResultsThese data showed that loss of TBCK did not inhibit mTORC1 activity in neither NPC nor neurons. Additionally, analysis of eight patient-derived cells and TBCK knock down HeLa cells showed that mTORC1 inhibition is inconsistent across different patients and cell types. We showed that TBCK knockdown in ReNcells affected NPC differentiation to neurons and astrocytes. Specifically, differentiation defects are coupled to cell cycle defects in NPC and increased cell death during differentiation. RNAseq analysis indicated the downregulation of several different neurodevelopmental and differentiation pathways. We observed a higher number of LC3-positive vesicles in the soma and neurites of TBCK knockdown cells. Further, TBCK knockdown altered mitochondrial dynamics and membrane potential in NPC, neurons and astrocytes. We found partial mitochondrial rescue with the mitochondrial fission inhibitor mdivi- 1. DiscussionThis work outlines a new Human Cell Model for TBCK-related neurodegeneration and the essential role of mitochondrial health and partial rescue with mitochondrial fission inhibitor. This data, along with human neurons and astrocytes, illuminate mechanisms of neurodegeneration and provide a possible novel therapeutic avenue for affected patients.

neuroscience↗