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Torres, V.

Publications and source records attributed to Torres, V..

5 recordsLinked to original sources

Evolution of endogenized densoviral elements across aphid species

AO_SCPLOWBSTRACTC_SCPLOWEndogenous viral elements (EVEs) are widespread across animal genomes, yet the processes governing EVE evolution and diversification remain poorly understood. Here, we characterize the evolution of densoviral EVEs and exogenous densoviruses across the aphid tribe Macrosiphini, an agriculturally important group in which exogenous densoviruses and their endogenous derivatives have been linked to the plastic production of wings. Using new genome assemblies, transcriptomics, and phylogenetic analysis, we find that EVE content varies extensively across species. Moreover, we discovered a novel densovirus that is vertically transmitted, but phylogenetic incongruence between other densoviruses and their hosts suggests that horizontal transmission may also occur. Finally, we show that EVE-mediated regulation of wing plasticity extends across species that use different environmental signals to induce winged offspring. Our study shows that in this system, the evolution of EVEs is highly variable and lineage-specific, generating genomic patterns that cannot be predicted from host evolutionary relationships.

evolutionary biology↗

Heritable viral symbionts in the family Iflaviridae are widespread among aphids

AO_SCPLOWBSTRACTC_SCPLOWHeritable microbes shape host phenotypes and are important drivers of evolution. While interactions between insects and bacterial symbionts have been extensively studied, the prevalence and consequences of insect-viral symbiosis are an open question. We show that viral symbionts in the family Iflaviridae are widespread among aphids, an important model for research on bacterial symbiosis. We discovered multiple new species of iflaviruses that are maintained in asexual lines without apparent fitness costs and are transmitted vertically from mothers to offspring. Using field data and phylogenetic evidence, we further show that aphid iflaviruses likely move horizontally across species, but through laboratory experiments, we demonstrated that horizontal transfer among species infesting the same host plants does not persist throughout clonal lineages. Using quantitative PCR and immunohistochemistry, we discovered that viral infections localize in the host fat bodies and developing embryos. Surprisingly, we also found viral infections inside bacteria-housing cells called bacteriocytes, with a positive correlation between viral and bacterial symbiont density, indicating a mechanism for vertical transmission. Together, our work suggests that iflaviruses are an important but previously unrecognized piece of aphid symbiosis and sets the stage to use this model to answer new questions about host-microbe associations. IO_SCPLOWMPORTANCEC_SCPLOWIn recent years, the rise of metatranscriptome sequencing has led to the rapid discovery of novel viral sequences in insects. However, few studies have carefully investigated the dynamics of insect-virus interactions to produce a general understanding of viral symbiosis. Aphids are a significant agricultural pest but also an important model for understanding the evolution of host-microbe interactions and the molecular basis of bacterial symbiosis. We show that heritable iflaviruses are an important but previously unrecognized part of the aphid heritable microbiome, with viral symbionts transmitted alongside bacteria from mothers to offspring, potentially via specialized bacteriocytes that house symbiotic microbes. Our findings have important implications for furthering the understanding of insect-microbe symbiosis and the potential for biocontrol of agriculturally relevant pest species.

evolutionary biology↗

DeltaAI: Semi-Autonomous Tissue Grossing Measurements and Recommendations using Neural Radiance Fields for Rapid, Complete Intraoperative Histological Assessment of Tumor Margins

Mohs Micrographic Surgery (MMS) aims to excise cutaneous cancer with real-time margin analysis. However, manual tissue grossing and analysis can be inefficient, so we propose DeltaAI, a novel workflow that utilizes Neural Radiance Fields (NeRF) to enable rapid tissue grossing and generate a 3D model in an augmented reality (AR) environment. In our study, we captured 30-second videos of 17 MMS specimens using a photogrammetry turntable and cellphone camera. Preprocessing the tissues with segmentation models, we created a dataset of 923, 360-degree-view, images per video (17 videos). Using COLMAP, we estimated poses for sparse tissue reconstructions and trained the NeRF model for 3D volumetric tissue renderings. The results demonstrated that DeltaAI generated more accurate and complete 360-degree, 3D tissue renderings compared to previous models, while also achieving significantly faster runtimes. Our proposed semi-autonomous NeRF-based workflow has the potential to enhance the speed of MMS specimen processing, measurement, report generation, and margin assessment. It can inform real-time grossing decisions, automate the export of electronic health record data, and facilitate time-efficient and complete cancer excisions. Moreover, DeltaAI can contribute to the wider adoption of AI technology in clinical settings by improving tissue modeling for manual grossing.

pathology↗

A comparative study of in vitro air-liquid interface culture models of the human airway epithelium evaluating cellular heterogeneity and gene expression at single cell resolution

The airway epithelium is composed of diverse cell types with specialized functions that mediate homeostasis and protect against respiratory pathogens. Human airway epithelial cultures at air-liquid interface (HAE) are a physiologically relevant in vitro model of this heterogeneous tissue, enabling numerous studies of airway disease1-7. HAE cultures are classically derived from primary epithelial cells, the relatively limited passage capacity of which can limit experimental methods and study designs. BCi-NS1.1, a previously described and widely used basal cell line engineered to express hTERT, exhibits extended passage lifespan while retaining capacity for differentiation to HAE5. However, gene expression and innate immune function in HAE derived from BCi-NS1.1 versus primary cells have not been fully characterized. Here, combining single cell RNA-Seq (scRNA-Seq), immunohistochemistry, and functional experimentation, we confirm at high resolution that BCi-NS1.1 and primary HAE cultures are largely similar in morphology, cell type composition, and overall transcriptional patterns. While we observed cell-type specific expression differences of several interferon stimulated genes in BCi-NS1.1 HAE cultures, we did not observe significant differences in susceptibility to infection with influenza A virus and Staphylococcus aureus. Taken together, our results further support BCi-NS1.1-derived HAE cultures as a valuable tool for the study of airway infectious disease.

cell biology↗

Vasculature-associated adipose tissue macrophages dynamically adapt to inflammatory and metabolic challenges

Tissue-resident macrophages comprise the most abundant immune cell population in healthy adipose tissue. Adipose tissue macrophage populations change during metabolic stress and ageing, and are thought to contribute to the pathogenesis of obesity. Here, we studied adipose tissue macrophage subpopulations in the steady state, and in response to nutritional and infectious challenges.\n\nUsing comprehensive cell-surface-based and gene expression analyses, we found that tissue-resident macrophages from healthy epididymal white adipose tissue (eWAT) tightly associate with blood vessels, displaying a very high endocytic capacity. We refer to these cells as Vasculature-associated Adipose tissue Macrophages (VAMs). Chronic high fat diet (HFD) feeding results in the accumulation of a monocyte-derived CD11c+CD64+ double positive (DP) macrophage eWAT population with a predominant anti-inflammatory gene profile, but reduced endocytic function. In contrast, fasting rapidly and reversibly leads to VAM depletion, while acute inflammatory stress induced by pathogens transiently depletes VAMs and simultaneously boosts DP macrophage accumulation. Our results indicate that adipose tissue macrophage populations adapt to metabolic stress and inflammation, suggesting an important role for these cells in restoring homeostasis.

immunology↗