Biology subjects

Benes, V.

Publications and source records attributed to Benes, V..

At least 37 records · Page 2Linked to original sources

bioRxiv2023

Epigenetic deregulation of IFN and WNT pathways in AT2 cells impairs alveolar regeneration (in COPD)

Chronic lung diseases, including chronic obstructive pulmonary disease (COPD), affect over 500 million people and are a leading cause of death worldwide. A common feature of both chronic and acute lung diseases is altered respiratory barrier integrity and impaired lung regeneration. We hypothesized that alveolar type 2 (AT2) cells, as alveolar epithelial progenitors, will carry molecular alterations that compromise alveolar regeneration in COPD. Sorted AT2 cells from ex-smokers with and without COPD at different disease stages were subjected to RNA sequencing and whole-genome bisulfite sequencing to generate unbiased transcriptome and DNA methylation maps of alveolar progenitors in the lung. Our analysis revealed genome-wide epigenetic changes in AT2 cells during COPD that were associated with global gene expression changes. Integrative data analysis uncovered a strong anti-correlation between gene expression and promoter methylation, suggesting that dysregulation of COPD-associated pathways in AT2 cells may be regulated by DNA methylation. Interferon (IFN) signaling was the top-upregulated pathway associated with the concomitant loss of promoter DNA methylation. Epigenetic regulation of the IFN pathway was validated in both global and targeted DNA demethylation assays in A549 cells. Notably, targeted DNA demethylation of IRF9 triggered upregulation of IFN signaling, mimicking the effects observed in COPD AT2 cells in the profiling data. Our findings suggest that COPD-triggered epigenetic alterations in AT2 cells may impair internal regeneration programs in human lung parenchyma.

cell biology↗

bioRxiv2023

Gut microbiome remains stable following COVID-19 vaccination in healthy and immuno-compromised individuals

The bidirectional interaction between the immune system and the gut microbiota is a key contributor to various host physiological functions. Immune-associated diseases such as cancer and autoimmunity, as well as the efficacy of immunomodulatory therapies, have been linked to microbiome variation. While COVID-19 infection has been shown to cause microbial dysbiosis, it remains understudied whether the inflammatory response associated with vaccination also impacts the microbiota. Here, we investigate the temporal impact of COVID-19 vaccination on the gut microbiome in healthy and immuno-compromised individuals; the latter included patients with primary immunodeficiency and cancer patients on immunomodulating therapies. We find that the gut microbiome remained remarkably stable post-vaccination irrespective of diverse immune status, vaccine response, and microbial composition spanned by the cohort. The stability is evident at all evaluated levels including diversity, phylum, species, and functional capacity. Our results indicate the resilience of the gut microbiome to host immune changes triggered by COVID-19 vaccination and suggest minimal, if any, impact on microbiome-mediated processes. These findings encourage vaccine acceptance, particularly when contrasted with the significant microbiome shifts observed during COVID-19 infection.

microbiology↗

bioRxiv2023

A signalling rheostat controls chromosome segregation fidelity during early lineage specification and neurogenesis by modulating DNA replication stress

The development and homeostasis of organisms rely on the correct replication, maintenance and segregation of their genetic blueprints. How these intracellular processes are monitored across generations of different human cellular lineages, and why the spatio-temporal distribution of mosaicism varies during development remain unknown. Here, we identify several lineage specification signals that regulate chromosome segregation fidelity in both human and mouse pluripotent stem cells. Through epistatic analyses, we find that that WNT, BMP and FGF form a signalling "rheostat" upstream of ATM that monitors replication fork velocity, origin firing and DNA damage during S-phase in pluripotency, which in turn controls spindle polymerisation dynamics and faithful chromosome segregation in the following mitosis. Cell signalling control of chromosome segregation fidelity declines together with ATM activity after pluripotency exit and specification into the three human germ layers, or further differentiation into meso- and endoderm lineages, but re-emerges during neuronal lineage specification. In particular, we reveal that a tug-of-war between FGF and WNT signalling in neural progenitor cells results in DNA damage and chromosome missegregation during cortical neurogenesis, which could provide a rationale for the high levels of mosaicism in the human brain. Our results highlight a moonlighting role of morphogens, patterning signals and growth factors in genome maintenance during pluripotency and lineage specification, which could have important implications for our understanding on how mutations and aneuploidy arise during human development and disease. One sentence summaryDevelopmental signals link genome maintenance to cell fate

cell biology↗

bioRxiv2023

Transcriptional and epigenomic profiling identifies YAP signaling as a key regulator of intestinal epithelium maturation

During intestinal organogenesis, equipotent epithelial progenitors mature into phenotypically distinct stem cells that are responsible for life-long maintenance of the tissue. While the morphological changes associated with the transition are well-characterized, the molecular mechanisms underpinning the maturation process are not fully understood. Here, we leverage intestinal organoid cultures to profile transcriptional, chromatin accessibility, DNA methylation and 3D chromatin conformation landscapes defining fetal and adult epithelial cells. We observed prominent differences in gene expression and enhancer activity, accompanied by changes in 3D organization and local changes in DNA accessibility and methylation, between the two cellular states. Using integrative analyses, we identified sustained YAP transcriptional activity as a major gatekeeper of the immature fetal state. We found the YAP-associated transcriptional network to be regulated at various levels of chromatin organization, and likely to be coordinated by changes in extracellular matrix composition. Altogether, our work highlights the value of unbiased profiling of regulatory landscapes for the identification of key mechanisms underlying tissue maturation.

developmental biology↗

bioRxiv2022

Co-translational binding of importins to nascent proteins

Various cellular quality control mechanisms support proteostasis. While, ribosome-associated chaperones prevent misfolding of nascent chains during translation, importins were shown to prevent the aggregation of specific cargoes in a post-translational mechanism prior the import into the nucleoplasm. Here, we hypothesized that importins may already bind ribosome-associated cargo in a co-translational manner. We systematically measured the nascent chain association of all importins in Saccharomyces cerevisiae by selective ribosome profiling. We identified a subset of importins that bind to a wide range of nascent, often uncharacterized cargoes. This included ribosomal proteins, chromatin remodelers and RNA binding proteins that are aggregation prone in the cytosol. We show that importins act consecutively with other ribosome-associated chaperones. Thus, the nuclear import system is directly intertwined with nascent chain folding and chaperoning. One-Sentence SummaryWe describe an unanticipated connection between co-translational protein chaperoning and the nuclear import system.

molecular biology↗

bioRxiv2022

Clonally resolved single-cell multi-omics identifies routes of cellular differentiation in acute myeloid leukemia

Inter-patient variability and the similarity of healthy and leukemic stem cells have impeded the characterization of leukemic stem cells (LSCs) in acute myeloid leukemia (AML), and their differentiation landscape. Here, we introduce CloneTracer, a novel method that adds clonal resolution to single-cell RNA-seq datasets. Applied to samples from 19 AML patients, CloneTracer revealed routes of leukemic differentiation. While residual healthy cells dominated the dormant stem cell compartment, active leukemic stem cells resembled their healthy counterpart and retained erythroid capacity. By contrast, downstream myeloid progenitors were highly aberrant and constituted the disease-defining compartment: Their gene expression and differentiation state determined both chemotherapy response and the leukemias ability to differentiate to transcriptomically normal monocytes. Finally, we demonstrated the potential of CloneTracer to identify surface markers mis-regulated specifically in leukemic cells by intra-patient comparisons. Taken together, CloneTracer revealed a differentiation landscape that mimics its healthy counterpart and determines biology and therapy response in AML.

cancer biology↗

bioRxiv2022

High-resolution epigenetic profiling identifies novel regulators of COPD in human lung fibroblasts

Patients with chronic obstructive pulmonary disease (COPD) are still waiting for curative treatments. Considering the environmental cause of COPD (e.g., cigarette smoke) and disease phenotypes, including stem-cell senescence and impaired differentiation, we hypothesized that COPD will be associated with altered epigenetic signaling in lung cells. We generated genome-wide DNA methylation maps at single CpG resolution of primary human lung fibroblasts (HLFs) isolated from distal parenchyma of ex-smoker controls and COPD patients, with both mild and severe disease. The epigenetic landscape is markedly changed in lung fibroblasts across COPD stages, with DNA methylation changes occurring predominantly in regulatory regions, including promoters and enhancers. RNA sequencing of matched fibroblasts demonstrated dysregulation of genes involved in proliferation, DNA repair, and extracellular matrix organization. Notably, we identified epigenetic and transcriptional dysregulation already in mild COPD patients, providing unique insights into early disease. Integration of profiling data identified 110 candidate regulators of disease phenotypes, including epigenetic factors. Using phenotypic screens, we verified the regulator capacity of multiple candidates and linked them to repair processes in the human lung. Our study provides first integrative high-resolution epigenetic and transcriptomic maps of human lung fibroblasts across stages of COPD. We reveal novel transcriptomic and epigenetic signatures associated with COPD onset and progression and identify new candidate regulators involved in the pathogenesis of chronic respiratory diseases. The presence of various epigenetic factors among the candidates demonstrates that epigenetic regulation in COPD is an exciting research field that holds promise for novel therapeutic avenues for patients.

cell biology↗

bioRxiv2022

Revealing genomic changes responsible for cannabinoid receptor loss in parrots: mechanism and functional effects

In vertebrates, an ancient duplication in the genes for cannabinoid receptors (CNRs) allowed the evolution of specialised endocannabinoid receptors expressed in the brain (CNR1) and the periphery (CNR2). While dominantly conserved throughout vertebrate phylogeny, our comparative genomic analysis suggests that certain taxa may have lost either the CNR1 regulator of neural processes or, more frequently, the CNR2 involved in immune regulation. Focussing on conspicuous CNR2 pseudogenization in parrots (Psittaciformes), a diversified crown lineage of cognitively-advanced birds, we highlight possible functional effects of such a loss. Parrots appear to have lost the CNR2 gene at at least two separate occasions due to chromosomal rearrangement. Using gene expression data from the brain and periphery of birds with experimentally-induced sterile inflammation, we compare CNR and inflammatory marker (interleukin 1 beta, IL1B) expression patterns in CNR2-deficient parrots (represented by the budgerigar, Melopsittacus undulatus and five other parrot species) with CNR2-intact passerines (represented by the zebra finch, Taeniopygia guttata). Though no significant changes in CNR expression were observed in either parrots or passerines during inflammation of the brain or periphery, we detected a significant up-regulation of IL1B expression in the brain after stimulation with lipopolysaccharide (LPS) only in parrots. As our analysis failed to show evidence for selection on altered CNR1 functionality in parrots, compared to other birds, CNR1 is unlikely to be involved in compensation for CNR2 loss in modulation of the neuroimmune interaction. Thus, our results provide evidence for the functional importance of CNR2 pseudogenization for regulation of neuroinflammation.

genomics↗

bioRxiv2021

Expanded FLP toolbox for spatiotemporal protein degradation and transcriptomic profiling in C. elegans

Control of gene expression in specific tissues and/or at certain stages of development allows the study and manipulation of gene function with high precision. Site-specific genome recombination by the Flippase (FLP) and Cre enzymes has proven particularly relevant. Joint efforts of many research groups have led to the creation of efficient FLP and Cre drivers to regulate gene expression in a variety of tissues in Caenorhabditis elegans. Here, we extend this toolkit by the addition of FLP lines that drive recombination specifically in distal tip cells, the somatic gonad, coelomocytes and the epithelial P lineage. In some cases, recombination-mediated gene knockouts do not completely deplete protein levels due to persistence of long-lived proteins. To overcome this, we developed a spatiotemporally regulated degradation system for GFP fusion proteins (GFPdeg) based on FLP-mediated recombination. Using two stable nuclear pore proteins, MEL-28/ELYS and NPP-2/NUP85 as examples, we report the benefit of combining tissue-specific gene knockout and protein degradation to achieve complete protein depletion. We also demonstrate that FLP-mediated recombination can be utilized to identify transcriptomes in a C. elegans tissue of interest. We have adapted RNA polymerase DamID (RAPID) for the FLP toolbox and by focusing on a well-characterized tissue, the hypodermis, we show that the vast majority of genes identified by RAPID are known to be expressed in this tissue. These tools allow combining FLP activity for simultaneous gene inactivation and transcriptomic profiling, thus enabling the inquiry of gene function in various complex biological processes.

genetics↗

bioRxiv2021

Drivers and Determinants of Strain Dynamics Following Faecal Microbiota Transplantation

Faecal microbiota transplantation (FMT) is an efficacious therapeutic intervention, but its clinical mode of action and underlying microbiome dynamics remain poorly understood. Here, we analysed the metagenomes associated with 142 FMTs, in a time series-based meta-study across five disease indications. We quantified strain-level dynamics of 1,089 microbial species based on their pangenome, complemented with 47,548 newly constructed metagenome-assembled genomes. Using subsets of procedural-, host- and microbiome-based variables, LASSO-regularised regression models accurately predicted the colonisation and resilience of donor and recipient microbes, as well as turnover of individual species. Linking this to putative ecological mechanisms, we found these sets of variables to be informative of the underlying processes that shape the post-FMT gut microbiome. Recipient factors and complementarity of donor and recipient microbiomes, encompassing entire communities to individual strains, were the main determinants of individual strain population dynamics, and mostly independent of clinical outcomes. Recipient community state and the degree of residual strain depletion provided a neutral baseline for donor strain colonisation success, in addition to inhibitive priority effects between species and conspecific strains, as well as putatively adaptive processes. Our results suggest promising tunable parameters to enhance donor flora colonisation or recipient flora displacement in clinical practice, towards the development of more targeted and personalised therapies.

microbiology↗

bioRxiv2021

Combi-Seq: Multiplexed transcriptome-based profiling of drug combinations using 1deterministic barcoding in single-cell droplets

Anti-cancer therapies often exhibit only short-term effects. Tumors typically develop drug resistance causing relapses that might be tackled with drug combinations. Identification of the right combination is challenging and would benefit from high-content, high-throughput combinatorial screens directly on patient biopsies. However, such screens require a large amount of material, normally not available from patients. To address these challenges, we developed a scalable microfluidic workflow to screen hundreds of drug combinations in picoliter-size droplets using transcriptome changes as a readout for drug effects. We devised a deterministic combinatorial DNA barcoding approach to encode treatment conditions, enabling the gene expression-based readout of drug effects in a highly multiplexed fashion. We applied our method to screen the effect of 420 drug combinations on the transcriptome of K562 cells using only [~]250 single cell droplets per condition, to successfully predict synergistic and antagonistic drug pairs, as well as their pathway activities.

systems biology↗

bioRxiv2021

Patient-derived gene and protein expression signatures of NGLY1 deficiency

N-Glycanase 1 (NGLY1) deficiency is a rare and complex genetic disorder. Although recent studies have shed light on the molecular underpinnings of NGLY1 deficiency, a systematic characterization of gene and protein expression changes in patient-derived cells has been lacking. Here, we performed RNA-sequencing and mass spectrometry to determine the transcriptomes and proteomes of 66 cell lines representing 4 different cell types derived from 14 NGLY1 deficient patients and 17 controls. While gene and protein expression levels agreed well with each other, expression differences were more pronounced at the protein level. Although NGLY1 protein levels were up to 9.5-fold downregulated in patients compared to parent controls, depending on the genotype, NGLY1 protein was still detectable in all patient-derived lymphoblastoid cell lines. Consistent with the role of NGLY1 as a regulator of the transcription factor Nrf1, we observed a cell type-independent downregulation of proteasomal genes in NGLY1 deficient cells. In contrast, genes involved in ribosomal mRNA processing were upregulated in multiple cell types. In addition, we observed cell type-specific effects. For example, genes and proteins involved in glutathione synthesis, such as the glutamate-cystein ligase subunits GCLC and GCLM, were downregulated specifically in lymphoblastoid cells. We provide a web application that enables access to all results generated in this study at https://apps.embl.de/ngly1browser. This resource will guide future studies of NGLY1 deficiency in directions that are most relevant to patients.

systems biology↗

bioRxiv2021

Co-translational assembly counteracts promiscuous interactions

During the co-translational assembly of protein complexes, a fully synthesized subunit engages with the nascent chain of a newly synthesized interaction partner. Such events are thought to contribute to productive assembly, but their exact physiological relevance remains underexplored. Here, we examined structural motifs contained in nucleoporins for their potential to facilitate co-translational assembly. We experimentally tested candidate structural motifs and identified several previously unknown co-translational interactions. We demonstrate by selective ribosome profiling that domain invasion motifs of beta-propellers, coiled-coils, and short linear motifs act as co-translational assembly domains. Such motifs are often contained in proteins that are members of multiple complexes (moonlighters) and engage with closely related paralogs. Surprisingly, moonlighters and paralogs assembled co-translationally in only one but not all of the relevant assembly pathways. Our results highlight the regulatory complexity of assembly pathways.

molecular biology↗

bioRxiv2021

Extensive OMICS resource for Sf21 and Tni cell lines

Insect-derived cell lines, from Spodoptera frugiperda (Sf21) and from Trichoplusia ni (Tni), are the two most widely used cell lines for recombinant protein expression in combination with the Baculoviral Expression Vector System (BEVS). Genomic sequences and annotations are still incomplete for Sf21 and absent for Tni. In this study, we present an approach using different sequencing data types, including short-read sequencing, long synthetic and Oxford Nanopore reads, to build genomes. The Sf21 and Tni assemblies contain 4,020 scaffolds of 463 Mb in size with N50 of 364 Kb and 2,954 scaffolds of 332 Mb in size with N50 of 326 Kb, respectively. Furthermore, we built a new gene prediction workflow, which integrates transcriptome and proteome information using pre-existing tools. Using this approach, we predicted 21,506 Sf21 and 14,159 Tni genes, generated and integrated proteomic datasets to validate predicted genes and could identify 5577 and 4919 proteins in the Sf21 and Tni cell lines respectively. This integrative approach could be theoretically applied to any uncharacterized genome and result in valuable new resources. With this information available, Sf21 and Tni cells will become even better tools for protein expression and could be used in a wider range of applications, from promoter identification to genome engineering and editing.

genomics↗

bioRxiv2021

Single-cell proteo-genomic reference maps of the hematopoietic system enable the purification and massive profiling of precisely defined cell states

Single-cell genomics has transformed our understanding of complex cellular systems. However, excessive costs and a lack of strategies for the purification of newly identified cell types impede their functional characterization and large-scale profiling. Here, we have generated high content single-cell proteo-genomic reference maps of human blood and bone marrow that quantitatively link the expression of up to 197 surface markers to cellular identities and biological processes across all major hematopoietic cell types in healthy aging and leukemia. These reference maps enable the automatic design of cost-effective high-throughput cytometry schemes that outperform state-of-the-art approaches, accurately reflect complex topologies of cellular systems, and permit the purification of precisely defined cell states. The systematic integration of cytometry and proteo-genomic data enables measuring the functional capacities of precisely mapped cell states at the single-cell level. Our study serves as an accessible resource and paves the way for a data-driven era in cytometry.

immunology↗

bioRxiv2021

Identification of developmentally important genes in Silene latifolia through chemical genetics and transcriptome profiling

Dioecious plants possess diverse sex determination systems and unique mechanisms of reproductive organ development; however, little is known about how sex-linked genes shape the expression of regulatory cascades that lead to developmental differences between sexes. In Silene latifolia, a dioecious plant with stable dimorphism in floral traits, early experiments suggested that female-regulator genes act on the factors that determine the boundaries of the flower whorls. To identify these regulators, we sequenced the transcriptome of male flowers with fully developed gynoecia induced by rapid demethylation in the parental generation. As the hermaphrodite flower trait is holandric (transmitted only from male to male, inherited on the Y chromosome), we screened for genes that are differentially expressed between male, female, and hermaphrodite flowers. Dozens of candidate genes that are upregulated in hermaphrodite flowers compared to male and female flowers were detected and found to have putative roles in floral organization, affecting the expression of floral MADS-box and other genes. Amongst these genes, eight candidates were found to promote gynoecium formation in female and hermaphrodite flowers, affecting organ size, whorl boundary, and the expression of mainly B class flower genes. To complement our transcriptome analysis, we closely examined the floral organs in their native state using a field emission environmental scanning electron microscope. Our results reveal the principal regulatory pathways involved in sex-specific flower development in the classical model of dioecy, S. latifolia.

plant biology↗

bioRxiv2021

Identification of LINE retrotransposons and long non-coding RNAs expressed in the octopus brain

BackgroundTransposable elements (TEs) widely contributed to the evolution of genomes allowing genomic innovations, generating germinal and somatic heterogeneity and giving birth to long non-coding RNAs (lncRNAs). These features have been associated to the evolution, functioning and complexity of the nervous system at such a level that somatic retrotransposition of long interspersed element (LINE) L1 has been proposed to be associated to human cognition. Among invertebrates, octopuses are fascinating animals whose nervous system reaches a high level of complexity achieving sophisticated cognitive abilities. The sequencing of the genome of the Octopus bimaculoides revealed a striking expansion of TEs which were proposed to have contributed to the evolution of its complex nervous system. We recently found a similar expansion also in the genome of Octopus vulgaris. However a specific search for the existence of full-length transpositionally competent TEs has not been performed in this genus. ResultsHere we report the identification of LINE elements competent for retrotransposition in Octopus vulgaris and Octopus bimaculoides and show evidence suggesting that they might be active driving germline polymorphisms among individuals and somatic polymorphisms in the brain. Transcription and translation measured for one of these elements resulted in specific signals in neurons belonging to areas associated with behavioral plasticity. We also report the transcription of thousands of lncRNAs and the pervasive inclusion of TE fragments in the transcriptomes of both Octopus species, further testifying the crucial activity of TEs in the evolution of the octopus genomes. ConclusionsThe neural transcriptome of the octopus shows the transcription of thousands of putative lncRNAs and of a full lenght LINE element belonging to the RTE class. We speculate that a convergent evolutionary process involving retrotransposons activity in the brain has been important for the evolution of sophisticated cognitive abilities in this genus.

genomics↗

bioRxiv2020

Aberrant replication licensing drives Copy Number Gains across species

Copy Number Gains (CNGs) lead to genetic heterogeneity, driving evolution and carcinogenesis. The mechanisms promoting CNG formation however remain poorly characterized. We show that abnormal expression of the replication licensing factor Cdc18 in fission yeast, which leads to genome-wide re-replication, drives the formation of CNGs at different genomic loci, promoting the acquisition of new selectable traits. Whole genome sequencing reveals Mb long, primarily extrachromosomal amplicons. Genetic analysis shows that homology-mediated repair is required to resolve re-replication intermediates into heritable CNGs. Consistently, we show that in mammalian cells overexpression of CDC6 and/or CDT1 leads to CNGs and promotes drug resistance. In human cells, multiple repair pathways are activated upon rereplication and act antagonistically, with RAD52 promoting and 53BP1 inhibiting CNG formation. In tumours, CDT1 and/or CDC6 overexpression correlates with copy number gains genome-wide. We propose re-replication as an evolutionary-conserved driver of CNGs, highlighting a link between aberrant licensing, CNGs and cancer.

molecular biology↗