Biology subjects

Winkler, S.

Publications and source records attributed to Winkler, S..

At least 19 recordsLinked to original sources

bioRxiv2026

Expecting the unexpected: Great apes anticipate surprise in others

Humans adeptly navigate complex social environments by attempting to anticipate the actions and emotional responses of others. Although our closest ape relatives have sophisticated social cognitive abilities, we do not know whether they have a cognitive understanding of others' emotions. For the epistemic emotion surprise, a cognitive understanding would require sensitivity to an agent's belief, to reality, and to any misalignment between the two, allowing one to model the mental conditions that drive surprise. In a non-invasive eye tracking study with 31 chimpanzees and bonobos, apes showed evidence of a cognitive understanding of surprise: they detected the misalignment between an agent's belief and reality, exhibiting greater pupil dilation right before an agent encountered an unexpected outcome relative to an expected one. This suggests that apes and humans share a more complex understanding of others' mental lives than previously thought, capacities that likely evolved millions of years ago in a common ancestor.

animal behavior and cognition↗

bioRxiv2026

The genome sequence of Seabra's wing-gland bat, Cistugo seabrae Thomas, 1912

We present a genome assembly from a female Cistugo seabrae (Seabras wing-gland bat; Chiroptera; Cistugidae). The genome sequence is 1.9 gigabases (Gb) in span. The majority of the assembly is scaffolded into 25 chromosomal pseudomolecules, with the XX chromosomes assembled. The assembly has a contig N50 of 51.9 Mb and a scaffold N50 of 91.4 Mb. Species taxonomyEukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Laurasiatheria; Chiroptera; Yangochiroptera; Vespertilionoidea; Cistugidae; Cistugo; Cistugo seabrae Thomas, 1912 (Teeling et al., 2005; Bickham et al., 2004; Lack et al., 2010).

genomics↗

bioRxiv2026

Integrated genomics and transcriptomics reveal mechanisms of extreme dietary adaptation in vampire bats

Vampire bats are the only tetrapods that feed exclusively on blood. To uncover the molecular basis of this extreme dietary specialization, we generated six new reference genomes, including genomes of all three vampire bat species, and integrated comparative analyses of gene sequence evolution (selection signatures, duplications, and losses) with transcriptomic data from six major organs to identify shifts in gene expression. Our integrative analyses reveal sequence or expression changes in 150 genes that illuminate the genetic mechanisms underlying sanguivory. Through comparative analyses and experiments, we show that the enlarged vampire bat stomach has increased connective tissue content enabling extreme expansion, is pH-neutral, and exhibits reduced mucus production, together providing molecular insights into its shift from a digestive to an absorptive organ for water, electrolytes, and vitamins. We further uncover pathway-level molecular changes underlying altered gastrointestinal motility; trypsin-dependent protein digestion; upregulated amino acid catabolism with key aspects diverging from other mammals; impaired dietary fat digestion counterbalanced by increased fatty acid synthesis; defective sugar metabolism and natural insulin deficiency; enhanced heme iron absorption; and adult splenic erythropoiesis. Together, these findings reveal the molecular adaptations that enable one of the most extreme dietary transitions among vertebrates.

evolutionary biology↗

bioRxiv2026

An annotated bioacoustic dataset of dog vocalizations and related sounds during dog-human social play

Dog (Canis lupus familiaris) vocal communication occurs across a wide range of social contexts, including dog-human social play, a common and dynamic interaction in which diverse vocal signals are expressed, particularly in young dogs. However, most available open datasets of dog vocalizations focus primarily on barks, leaving other sound types underrepresented. Here we present a bioacoustic dataset of dog-human social play sessions recorded under standardized laboratory conditions, comprising 30 play sessions involving 17 young dogs (6-24 months old) of different breeds playing with familiar humans. Raw audio recordings are accompanied by two layers of annotations covering the dog sounds produced during sessions. Video recordings of the sessions are provided for contextual reference, along with metadata describing each dog and the experimental sessions. Additionally, permutation-based classification analysis showed that annotated sound categories exhibit above-chance and generalizable acoustic differences across individuals. The dataset may support research on dog vocal communication and expand the range of sounds documented during positive dog-human social interactions.

animal behavior and cognition↗

bioRxiv2026

Beyond Delta Masses: MS Andrea Directly Resolves Combinatorial Peptide Modifications in Open Searches

Open modification search (OMS) strategies have gained popularity in mass spectrometry-based proteomics for identification of peptides carrying unknown or unexpected post-translational modifications. However, most OMS engines report only the overall mass difference between precursor and matched peptide, without explicitly identifying or scoring combinations of modifications at the PSM level. Here, we introduce MS Andrea, a novel OMS search engine that directly identifies and scores combinations of modifications without predefining them. MS Andrea uses a sequence tag-based strategy to filter candidate peptides, evaluated using the MS Amanda scoring function. First fixed modifications only, then combinations of modifications from the Unimod database based on the observed mass shift. We evaluated MS Andrea using a human histone dataset and two phosphopeptide datasets (HeLa cells and Arabidopsis thaliana), comparing its performance with MSFragger and Sage. Across datasets, MS Andrea identified the highest number of PSMs at 1 % FDR using the standard target-decoy approach while achieving higher or comparable numbers using model-based FDR estimation. Importantly, MS Andrea reports modification identities and sites for up to four modifications at the PSM level. Together, these results demonstrate that MS Andrea enables more detailed, interpretable characterization of peptide modifications while maintaining competitive identification performance in OMS-based proteomics.

molecular biology↗

bioRxiv2026

Side-necked turtle genomes reveal chromosomal dynamics, skeletal innovation and cancer resistance

Turtles exhibit a highly derived body plan, exceptional longevity, cancer resistance, and striking diversity in karyotypes and sex determination systems. However, the genomic basis of these innovations remains unresolved, largely because reference genomes were lacking for one of two extant turtle clades, the side-necked turtles (Pleurodira). As part of the Vertebrate Genomes Project, we generated seven reference-quality Pleurodira genomes and reconstructed the most comprehensive genome-wide turtle phylogeny. Combining demographic inference with historical climate and biome reconstructions indicates that ancient climate fluctuations shaped long-term population dynamics, while recent declines mainly reflect population structure. Ancestral genome reconstructions reveal that rare bursts of chromosome fusions and fissions, likely facilitated by repetitive elements, drove turtle karyotype diversity. By identifying sex chromosomes and tracing their evolutionary history, we resolve a long-standing debate and demonstrate a single origin of genetic sex determination in Chelidae on a microchromosome over 80 million years ago. Contrary to previous hypotheses, we find no evidence of coevolution between genetic sex determination and chromosome number in turtles. Comparative genomic analyses further identify gene losses and signatures of adaptive evolution associated with key turtle traits. Gene losses causing disproportionate dwarfism phenotypes may have contributed to skeletal adaptations underlying the compact turtle body plan. In addition, gene losses and adaptive changes in stress response and tumor suppressor pathways likely enhance oxidative stress tolerance and cancer resistance. Together, these findings illuminate turtle genome evolution, revealing chromosomal dynamics, sex chromosome evolution, molecular insights into skeletal innovation and cancer resistance, and implicate gene losses as a recurrent contributor to evolutionary novelty.

genomics↗

bioRxiv2026

Genomic analyses demonstrate the absence of genetic sex determination in the dioecious conifer Taxus baccata

Hundreds of plant lineages have independently evolved dioecy, i.e., separation of female and male flowers on different individuals. In all dioecious plants investigated at the molecular level to date, sex is determined genetically through a sex-determining region (SDR). SDRs have mostly been studied in angiosperms, although dioecy is relatively more common among gymnosperms. Here, we investigate sex determination in the gymnosperm Taxus baccata. We assembled four haplotype-resolved chromosome-level genomes for one female and one male tree, with an average size of 10.04 Gb, and generated resequencing data for 100 phenotypically sexed individuals. Strikingly, k-mer analyses, genome-wide association studies and differential coverage analyses demonstrate the absence of an SDR in the T. baccata genome. This indicates a non-genetic mechanism of sex determination, most likely via a sex-specific epiallele. Given that T. baccata is the first species studied among a large group of conifers, our findings suggest that such a mechanism might be widespread.

plant biology↗

bioRxiv2025

Unified down-stream analysis of crosslinking mass spectrometry results with pyXLMS

Crosslinking mass spectrometry has become the method of choice for the identification of protein-protein interactions and for gaining insight into the structures of proteins in vivo. However, connecting crosslink search engine results with down-stream analysis tools, and therefore gaining biological insight from crosslink identifications, has remained a manual and cumbersome step in the analysis that often requires expert bioinformatics knowledge. Here we introduce pyXLMS, a python package and public web application which aims to simplify and streamline this intermediate step, enabling researchers even without bioinformatics knowledge to conduct in-depth crosslink analyses. In its current state pyXLMS supports input from seven different crosslink search engines, as well as the mzI-dentML format of the HUPO Proteomics Standards Initiative. Down-stream analysis is facilitated by functionality that is directly available within pyXLMS such as aggregation, validation, annotation, filtering, and visualization. In addition, the data can easily be exported to more than ten supported down-stream analysis tools and formats. We demonstrate the applicability and benefits of pyXLMS by re-analyzing a publicly available crosslink dataset with a variety of different search engines and show how the same data analysis workflow can be applied using pyXLMS. pyXLMs is available via https://github.com/hgb-bin-proteomics/pyXLMS.

bioinformatics↗

bioRxiv2025

Retrocopy formation and domestication shape genome evolution in sloths and other xenarthrans

Xenarthrans, comprising sloths, anteaters, and armadillos, represent one of the most morphologically and physiologically specialised mammalian clades, yet the genomic basis of their adaptations remains poorly understood. Here, we present chromosome-level genomes for the two-toed sloth (Choloepus didactylus) and the southern anteater (Tamandua tetradactyla), and investigate how retrotransposon-mediated gene duplications (retrocopies) have shaped xenarthran genome evolution. Comparative analyses revealed that xenarthran genomes harbor the highest number of retrocopies reported among mammals, with lineage-specific insertion dynamics. Anteater and armadillo genomes contain older LINE1 repertoires and species-specific older retrocopy insertions. In contrast, sloths retain both an abundance of young LINE1s and thousands of young retrocopies, alongside a large shared set that originated from an evolutionary burst of retroduplication in the branch leading to their last common ancestor ([~]30 Mya). In C. didactylus, approximately 50% of retrocopies are expressed, compared with 24% in Dasypus novemcinctus. Evolutionary analyses identified 38 retrocopies with strong hallmarks of domestication in C. didactylus. Many of these retrocopies derive from parental genes involved in mitochondrial and metabolic processes, suggesting a genomic mechanism underlying the physiological specialisations of sloths. Altogether, our findings identify retrotransposition as a major contributor to the genomic architecture of Xenarthra and highlight retrocopy origination as a mechanism for generating lineage-specific novelty and distinctive biological specialisations.

genomics↗

bioRxiv2025

Systematic discovery of bacterial symbionts in rumen ciliate protozoa

Microbial interactions are fundamental to global ecological and evolutionary processes, exemplified by endosymbiosis between prokaryotes and single-cell eukaryotes that gave rise to organelles. While such associations remain widespread and ecologically important, the diversity and evolutionary dynamics of intracellular symbioses in many microbial ecosystems remain poorly understood. Here, we uncover a hidden layer of microbial complexity in the rumen ecosystem by identifying multiple endosymbiotic associations between ciliate protozoa and bacteria. Using genome-resolved metagenomics on protozoa enriched rumen fractions, we reveal diverse bacterial genomes exhibiting hallmarks of an obligate intracellular lifestyle. These candidate symbionts span several bacterial phyla and include close relatives of known endosymbionts and parasites of protists as well as previously unclassified or presumed free-living bacterial lineages that likely represent overlooked symbiont specialists. Our findings therefore expand the known distribution of bacterial endosymbiosis, establish the rumen - a key site of global carbon and nitrogen cycling - as a promising model for symbiosis research, and demonstrate the power of our approach to uncover hidden symbiotic associations across complex microbial communities. Overall, our results highlight the ubiquity and evolutionary significance of intracellular symbiosis as a shaping force in microbial ecosystems.

microbiology↗

bioRxiv2025

Cryptocercus genomes expand knowledge of adaptations to xylophagy and termite sociality

Subsociality and wood-eating or xylophagy are understood as key drivers in the evolution of eusociality in Blattodea (cockroaches and termites), two features observed in the cockroach genus Cryptocercus, the sister group of all termites. We present and analyse two new high-quality genomes from this genus, C. punctulatus from North America and C. meridianus from Southeast Asia, to explore the evolutionary transitions to xylophagy and subsociality within Blattodea. Our analyses reveal evidence of relaxed selection in both Cryptocercus and termites, indicating that a reduction in effective population size may have occurred in their subsocial ancestors. These findings challenge the expected positive correlation between dN/dS ratios and social complexity, as Cryptocercus exhibits elevated dN/dS values that may exceed those of eusocial termites. Additionally, we identify positive selection on mitochondrial ribosomal proteins and components of the NADH dehydrogenase complex, suggesting significant evolutionary changes in energy production. Future studies incorporating additional genomic data from diverse blattodean species are essential to elucidate the molecular mechanisms driving transitions to xylophagy and eusociality.

evolutionary biology↗

bioRxiv2024

Diverging repeatomes in holoparasitic Hydnoraceae uncover a playground of genome evolution

O_LIThe nuclear genomes of parasitic plants have undergone unique evolutionary trajectories to adapt to the heterotrophic lifestyle. These adaptations often involve large genomic alterations, potentially driven by repetitive DNAs. Despite the recognized role of repetitive DNAs for shaping plant genomes, their contribution to parasitic plant genome evolution remains largely unexplored. This study presents the first analysis of repetitive DNAs in eleven genomes of Hydnoraceae, a holoparasitic plant family. C_LIO_LIThe repetitive DNAs were identified and annotated de novo. Patterns of abundance and presence-absence were aligned with the phylogenetic relationships, geographical distribution, and host shifts, suggesting repetitive DNAs key role in shaping Hydnoraceae genomes. C_LIO_LIThe two Hydnoraceae genera, Hydnora and Prosopanche, exhibit distinct profiles. Eight Hydnora genomes are largely populated by long terminal repeat retrotransposons, while three Prosopanche genomes vary greatly in repetitive DNA composition, including P. bonacinae with massive amplifications of a single DNA transposon and P. panguanensis with over 15% 5S rDNA, compared to <0.1% in some Hydnoraceae. Both extremely low and very high abundance of 5S rDNA challenges our current understanding on chromosomal stabilization and rDNA transcription. C_LIO_LIThese genome dynamics, while inviting for further investigations, suggest rapidly evolving repeat profiles, potentially accelerated by the adaptation to the parasitic lifestyle. C_LI

evolutionary biology↗

bioRxiv2024

Convergent and lineage-specific genomic changes contribute to adaptations in sugar-consuming birds

High-sugar diets cause human metabolic diseases, yet several bird lineages convergently adapted to feeding on sugar-rich nectar or fruits. We investigated the underlying molecular mechanisms in hummingbirds, parrots, honeyeaters, and sunbirds by generating nine new genomes and 90 tissue-specific transcriptomes. Comparative screens revealed an excess of repeated selection in both protein-coding and regulatory sequences in sugar-feeding birds, suggesting reuse of genetic elements. Sequence or expression changes in sugar-feeders affect genes involved in blood pressure regulation, lipid, amino acid and carbohydrate metabolism, with experiments showing functional changes in honeyeater hexokinase 3. MLXIPL, a key regulator of sugar and lipid homeostasis, showed convergent sequence and regulatory changes across all sugar-feeding clades; experiments revealed enhanced sugar-induced transcriptional activity of hummingbird MLXIPL, highlighting its adaptive role in high-sugar diets. Summary Figure: Our comparative screens across four independent sugar-feeding bird groups identified both repeated and lineage-specific targets of selection O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=65 SRC="FIGDIR/small/610474v2_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@148f5c8org.highwire.dtl.DTLVardef@1005dbaorg.highwire.dtl.DTLVardef@1097facorg.highwire.dtl.DTLVardef@9d365c_HPS_FORMAT_FIGEXP M_FIG C_FIG

evolutionary biology↗

bioRxiv2024

A genome resource for the marine annelid Platynereis dumerilii

The marine annelid Platynereis dumerilii is a model organism used in many research areas including evolution and development, neurobiology, ecology and regeneration. Here we present the genomes of P. dumerilii (laboratory culture reference and a single individual assembly) and of the closely related P. massiliensis and P. megalops (single individual assembly) to facilitate comparative genomic approaches and help explore Platynereis biology. We used long-read sequencing technology and chromosomal-conformation capture along with extensive transcriptomic resources to obtain and annotate a draft genome assembly of [~]1.47 Gbp for P. dumerilii, of which more than half represent repeat elements. We predict around 29,000 protein-coding genes, with relatively large intron sizes, over 38,000 non-coding genes, and 105 miRNA loci. We further explore the high genetic variation ([~]3% heterozygosity) within the Platynereis species complex. Gene ontology reveals the most variable loci to be associated with pigmentation, development and immunity. The current work sets the stage for further development of Platynereis genomic resources.

genomics↗

bioRxiv2024

Tissue inflammation induced by constitutively active STING is mediated by enhanced TNF signaling

Constitutive activation of STING by gain-of-function mutations triggers manifestation of the systemic autoinflammatory disease STING-associated vasculopathy with onset in infancy (SAVI). In order to investigate the role of signaling by tumor necrosis factor (TNF) in SAVI, we used pharmacological inhibition and genetic inactivation of TNF receptors 1 and 2 in murine SAVI, which is characterized by T cell lymphopenia, inflammatory lung disease and neurodegeneration. Pharmacologic inhibition of TNF signaling improved T cell lymphopenia, but had no effect on interstitial lung disease. Genetic inactivation of TNFR1 and TNFR2, however, rescued the loss of thymocytes, reduced interstitial lung disease and neurodegeneration. Furthermore, genetic inactivation of TNFR1 and TNFR2 blunted transcription of cytokines, chemokines and adhesions proteins, which result from chronic STING activation in SAVI mice. In addition, increased transendothelial migration of neutrophils was ameliorated. Taken together, our results demonstrate a pivotal role of TNFR-signaling in the pathogenesis of SAVI in mice and suggest that available TNFR antagonists could ameliorate SAVI in patients. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=170 HEIGHT=200 SRC="FIGDIR/small/591149v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@177cf0org.highwire.dtl.DTLVardef@b989dorg.highwire.dtl.DTLVardef@150a0c8org.highwire.dtl.DTLVardef@6bd42d_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2024

Long-read sequencing and genome assembly of natural history collection samples and challenging specimens

Museum collections harbor millions of samples, largely unutilized for long-read sequencing. Here, we use ethanol-preserved samples containing kilobase-sized DNA to show that amplification-free protocols can yield contiguous genome assemblies. Additionally, using a modified amplification-based protocol, employing an alternative polymerase to overcome PCR bias, we assembled the 3.1 Gb maned sloth genome, surpassing the previous 500 Mb protocol size limit. Our protocol also improves assemblies of other difficult-to-sequence molluscs and arthropods, including millimeter-sized organisms. By highlighting collections as valuable sample resources and facilitating genome assembly of tiny and challenging organisms, our study advances efforts to obtain reference genomes of all eukaryotes.

genomics↗

bioRxiv2023

A comparative analysis of planarian genomes reveals regulatory conservation in the face of rapid structural divergence

The planarian Schmidtea mediterranea can regenerate its entire body from small tissue fragments and is studied as regeneration model species. The assembly and functional analysis of planarian genomes has proven challenging due its high A/T content (70% A/T), repetitive nature, and limited transferability of routine laboratory protocols due to their divergent biochemistry. Only few and often fragmented genome assemblies are currently available, and open challenges include the provision of well-annotated chromosome-scale reference assemblies of the model species and other planarians for a comparative genome evolution perspective. Here we report a haplotype-phased, chromosome-scale genome assembly and high-quality gene annotations of the sexual S2 strain of S. mediterranea and provide putative regulatory region annotations via optimized ATAC-seq and ChIP-seq protocols. To additionally leverage sequence conservation for regulatory element annotations, we generated chromosome-scale genome assemblies and chromatin accessibility data for the three closest relatives of S. mediterranea: S. polychroa, S. nova, and S. lugubris. We find substantial divergence in protein-coding sequences and regulatory regions, yet reveal remarkable conservation in ChIP-mark bearing open chromatin regions identified as promoters and enhancers in S. mediterranea. The resulting high-confidence set of evolutionary conserved enhancers and promoters provides a valuable resource for the analysis of gene regulatory circuits and their evolution within the taxon. In addition, our four chromosome-scale genome assemblies provide a first comparative perspective on planarian genome evolution. Our analyses reveal frequent retrotransposon-associated chromosomal inversions and inter-chromosomal translocations that lead to a degradation of synteny across the genus. Interestingly, we further find independent and near-complete losses of the ancestral metazoan synteny across Schmidtea and two other flatworm groups, indicating that platyhelminth genomes largely evolve without syntenic constraints. Our work provides valuable genome resources for the planarian research community and sets a foundation for the comparative genomics of planarians. We reveal a contrast between the fast structural evolution of planarian genomes and the conservation of their regulatory elements, suggesting a unique genome evolution in flatworms where gene positioning may not be essential.

genomics↗

bioRxiv2023

A chromosome-level, haplotype-resolved genome assembly and annotation for the Eurasian minnow (Leuciscidae - Phoxinus phoxinus) provide evidence of haplotype diversity

AO_SCPLOWBSTRACTC_SCPLOWIn this study we present an in-depth analysis of the Eurasian minnow (Phoxinus phoxinus) genome, highlighting its genetic diversity, structural variations, and evolutionary adaptations. We generated an annotated haplotype-phased, chromosome-level genome assembly (2n = 50) by integrating high-fidelity (HiFi) long reads and chromosome conformation capture data (Hi-C). We achieved a haploid size of 940 Megabase pairs (Mbp) for haplome one and 929 Mbp for haplome two with high scaffold N50 values of 36.4 Mb and 36.6 Mb and BUSCO scores of 96.9% and 97.2%, respectively, indicating a highly complete genome assembly. We detected notable heterozygosity (1.43%) and a high repeat content (approximately 54%), primarily consisting of DNA transposons, which contribute to genome rearrangements and variations. We found substantial structural variations within the genome, including insertions, deletions, inversions, and translocations. These variations affect genes enriched in functions such as dephosphorylation, developmental pigmentation, phagocytosis, immunity, and stress response. In the annotation of protein-coding genes, 30,980 mRNAs and 23,497 protein-coding genes were identified with a high completeness score, which further underpins the high contiguity of our genome assemblies. We performed a gene family evolution analysis by comparing our proteome to ten other teleost species, which identified immune system gene families that prioritise histone-based disease prevention over NLR-based immune responses. Additionally, demographic analysis indicates historical fluctuations in the effective population size of P. phoxinus, likely correlating with past climatic changes. This annotated, phased reference genome provides a crucial resource for resolving the taxonomic complexity within the genus Phoxinus and highlights the importance of haplotype-phased assemblies in understanding haplotype diversity in species characterised by high heterozygosity.

genomics↗