Biology subjects

Prost, S.

Publications and source records attributed to Prost, S..

At least 19 recordsLinked to original sources

bioRxiv2026

Chromosome-level reference genome assembly of the Saimaa ringed seal (Pusa saimensis) - an ancient glacial relict landlocked pinniped

We present a high-quality chromosome-level reference genome for the Saimaa ringed seal (Pusa saimensis), an endangered freshwater pinniped endemic to Lake Saimaa, Finland. The assembly spans 2.353 Gb and comprises 15 autosomes together with the X and Y sex chromosomes. Using Oxford Nanopore Technologies (ONT) long-read sequencing and Hi-C scaffolding, we achieved a telomere-to-telomere assembly for all chromosomes, except the Y chromosome. Genome annotation identified approximately 21,800 protein-coding genes, consistent with other mammalian genomes. Assembly completeness was high, with BUSCO analysis recovering 99.6% of expected complete single-copy genes (98.2% single-copy and 1.3% duplicated). Comparative analyses revealed a highly conserved chromosomal architecture, with only minor syntenic differences relative to other pinniped chromosome-level assemblies. Previously described cytogenetic fusion events in Phocidae were confirmed (chromosomes 2 and 7). A translocation between chromosomes 6 and 7 distinguishes phocids from the otariids. In general, more distantly related taxa exhibit an increasing degree of intrachromosomal rearrangements. Notably, we identified a large intrachromosomal rearrangement on chromosome 2 that appears specific to the Saimaa ringed seal. Phylogenomic analysis based on 9,226 single-copy orthologues placed the Saimaa ringed seal as a sister lineage to the Baltic ringed seal (Pusa hispida botnica), while confirming also other established evolutionary relationships among pinnipeds. Comparative gene family analysis between the Saimaa ringed seal and the closely related grey seal (Halichoerus grypus) revealed lineage-specific differences driven by a limited number of gene families. In the Saimaa ringed seal, expansions were observed in ion transport, cytoskeleton, and regulatory genes, potentially reflecting adaptation to freshwater conditions. In contrast, the grey seal showed expansions in olfaction, immune-and spermatogenesis-associated gene families, including MAGE/MIA genes, consistent with differences in ecology and mating systems. This reference genome provides an important resource for studies of pinniped genome evolution, as well as conservation and population genomics of the Saimaa ringed seal, facilitating future work on genetic diversity, inbreeding, mutational load and adaptive potential in this highly endangered species.

genomics↗

bioRxiv2026

Genomic insights into Candidatus Argioplasma dusa, a bacterial symbiont of the wasp spider Argiope bruennichi

Bacterial symbionts were shown to have significant beneficial impacts on the fitness of their host in insects, but little is known on the symbionts of spiders and their interactions with their hosts. Here, we assembled and investigated the circular 575 kb genome of Candidatus Argioplasma dusa, a novel bacterial symbiont of the wasp spider Argiope bruennichi. Phylogenomic analysis placed this species within the phylum Tenericutes, in a poorly characterized clade that may represent a new order-level lineage or affiliate with the Mycoplasmatales order. With 559 predicted genes, the genome is relatively small compared to other Tenericutes genomes (on average 969 genes) and has a low GC content of ~24%. While the genome encodes genes for proteins involved in glycolysis and fermentative acetate production, it revealed minimal biosynthetic capabilities with pathways for nucleotide, amino acid and vitamin biosynthesis being absent in Ca. Argioplasma dusa. This suggests an intracellular endosymbiotic lifestyle within the spider host. The symbiont was detected in A. bruennichi populations across the distribution range of the spider but appears to be absent in certain populations.

microbiology↗

bioRxiv2025

A de novo reference genome of the golden jackal, Canis aureus

The golden jackal (Canis aureus) is rapidly expanding its range in Europe, driven by climate and habitat changes, human influence, and changes in competition with wolves. Its ecological flexibility enables it to thrive in various habitats, including urban areas, raising concerns about its potential role in spreading zoonotic diseases. Jackals may act as reservoirs for pathogens such as Lyme disease and babesiosis, affecting wildlife, humans, and pets. Their close genetic relationship with domestic dogs also increases the risk of hybridization and host-jumping, complicating disease dynamics. To better understand their dispersal ability and host-pathogen dynamics, we present the first chromosome-level genome assembly of the golden jackal, generated using PacBio HiFi sequencing and reference-based scaffolding. The final assembly has a total length of 2.53 Gb in 325 scaffolds, with 98.41% of the sequence anchored to the expected 38+XY chromosomes. The assembly shows high contiguity, with scaffold and contig N50 values of 68.03 Mb and 56.64 Mb, respectively. Annotation revealed 26,084 protein-coding genes, and repetitive elements account for 40.58% of the total assembly. This high-quality reference genome provides an essential resource for studying the genetic basis of the golden jackals adaptation, ecological interactions, and potential as a zoonotic reservoir. It also supports efforts to monitor population expansion and its effects on ecosystems. By advancing our understanding of golden jackal genetics, this work enables future research on evolution, host-pathogen dynamics, and the broader consequences of wildlife dispersal in a rapidly changing environment.

genomics↗

bioRxiv2025

Near-chromosome-level genome assembly and transcriptome of the Ural owl, Strix uralensis PALLAS, 1771

The Ural owl (Strix uralensis) is a large member of the Strigidae family and inhabits Eurasian forests ranging from Germany to Japan. However, it faces increased range reduction, particularly at its southwestern distribution edges. Despite being considered "Least Concern" by the IUCN, local populations have become threatened in Central Europe due to severe habitat loss. Reintroduction programs aim to restore these populations by closing distribution gaps and facilitating natural recolonization of suitable habitats. To support these efforts, genomic resources have become an established tool to assess genetic diversity, geographic structure, and potential inbreeding, crucial for maintaining the genetic health and adaptability of newly established populations. Here, we present a de novo genome assembly and transcriptome of the Ural owl based on ONT long-reads, Omni-C Illumina short-reads, and RNASeq data. The final assembly has a total length of 1.26 Gb, of which 96.37 % are anchored into the 41 largest scaffolds. The contig and scaffold N50 values of 88.6 Mb and 21.7 Mb, respectively, a BUSCO/compleasm completeness of 97.5 %/99.65 % and k-mer completeness of 95.18 %, emphasize the high quality of this assembly. Furthermore, annotation of the assembly identified 17,650 genes and a repeat content of 12.48 %. This new highly contiguous and chromosome-scale assembly will greatly benefit Ural owl conservation management by informing reintroduction programs about the species genetic health and contributing a valuable resource to study genetic function in greater detail across the whole Strigidae family.

genomics↗

bioRxiv2025

A Prelude to Conservation Genomics: First Chromosome-Level Genome Assembly of a Flying Squirrel (Pteromyini: Pteromys volans)

The Siberian flying squirrel (Pteromys volans) represents the only European Pteromyini species. Thus, it is biogeographically unique due to its specialised anatomy and biology as a volant rodent. As a result of habitat fragmentation and destruction, Siberian flying squirrels experience severe and ongoing population declines throughout most of their distribution. While considered Least Concern throughout their immense Eurasian distribution, this species is red-listed as Vulnerable and even Critically Endangered in parts of its range. More knowledge about the population structure and overall biology is needed to improve conservation efforts for this umbrella and flagship species of old-growth boreal forests. Here, we present the first chromosome-level genome assembly of any Pteromyini, represented by P. volans (Uoulu_pteVol_1.0). The final assembly has a total length of 2.85 Gbp in 19 chromosome-scale scaffolds with only minor differences in the chromosomal structure compared to other Sciuridae. All chromosome-scale scaffolds show indications for telomeres at both ends; the N50 value and busco as well as k-mer completeness scores are high with 157.39 Mbp and 97 - 99 %, respectively, indicating chromosome-level quality of the assembly. Based on whole-genome data from 17 rodent species, P. volans clusters according to known evolutionary relationships. Additionally, we present a new 16,511 bp long mitogenome unveiling differences from known conspecific mitogenomes. We propose the utility of the new reference genome for further research and development of conservation-applied genetic methods.

genomics↗

bioRxiv2025

Sequencing a botanical monument: a chromosome-level assembly of the 400-year-old Goethe's Palm (Chamaerops humilis L.) at the Botanical Garden of the University of Padua (Italy)

The rapid decline in global biodiversity highlights the urgent need for conservation efforts, with botanical gardens playing a crucial role in ex situ plant preservation. Monumental plants, such as the 400-year-old Goethes Palm (Chamaerops humilis L.) at the UNESCO Botanical Garden of the University of Padua (Italy), serve as vital flagship species with significant ecological and cultural value. In this study, we present the first high-quality, chromosome-level genome assembly of C. humilis, using PacBio HiFi and Arima Hi-C sequencing technologies. This genome is the most contiguous and complete within the Arecaceae family to date, with an exceptionally high repeat content of 88%, of which 63% is attributed to Long Terminal Repeat (LTR) elements. Comparative analysis of the transposable element (TE) landscape in palms suggests that the LTR expansion in C. humilis is likely the result of recent TE bursts. Furthermore, we provide the first comprehensive annotation of microRNAs (miRNAs) in the Arecaceae family, identifying, for the first time in palms, the miRNA family miR827, which plays a key role in nutrient regulation. Microsatellite analysis suggests that it probably belongs to the Western genetic lineage of C. humilis. These findings represent a significant advancement in the conservation genomics of this species, laying the groundwork for enhanced preservation strategies, with botanical gardens as pivotal actors in the fight to safeguard global biodiversity.

genomics↗

bioRxiv2024

Miniaturised laboratorial equipment as a solution to implement conservation genetics tools and education in West African countries with limited infrastructures: an application to the study of illegal wildlife trade in Guinea-Bissau

Illegal wildlife trade (IWT) is considered one of the largest global illegal industries that negatively impacts biodiversity and sustainable development worldwide. DNA barcoding coupled with high-throughput sequencing has been shown to be useful in identifying taxa affected by IWT and has been routinely used during the last decades. However, for countries lacking laboratory infrastructures and sequencing units or trained staff, the application of DNA barcoding tools in conservation actions and policies is limited and dependent on slow sample export processes and molecular analyses carried out abroad. Guinea-Bissau (GB) is located on the West-African coast and has one of the lowest human development indices worldwide, while being a biodiversity hotspot facing many conservation challenges due to illegal commercial hunting, and trade in bushmeat and live individuals. Here, we explore the potential of using inexpensive and portable miniaturised laboratory equipment (MLE) to i) identify species illegally traded in GB using DNA barcoding methods and ii) to improve molecular biology and conservation genetic education and training in GB. Our overarching aim is to raise awareness of the current gap between the need to apply conservation genetic technologies in GB and the inability to do so due to a lack of laboratory infrastructures, sequencing units and opportunities for molecular biology training. We show that MLE can be a solution to accelerate the use of DNA barcoding methods to understand IWT and to train students, technicians and staff from governmental agencies dedicated to investigating environmental crimes, ultimately advancing the discipline of conservation genetics in the country.

zoology↗

bioRxiv2024

Population structure of the endangered Siberian flying squirrel (Pteromys volans) revealed by genomic and mitochondrial data

The Siberian flying squirrel (Pteromys volans) is an arboreal rodent with a distribution range that covers large parts of the Eurasian taiga forest zone. However, extensive forestry has resulted in widespread local population declines and extinctions in recent decades. Even though it is widely distributed in Eurasia, almost nothing is known about its phylogeography. Here we used genome-wide single nucleotide polymorphisms (SNPs) and mitochondrial DNA (mtDNA) to investigate population structure, connectivity and genetic diversity in different sites throughout its distribution. Overall, the species shows low nucleotide diversity and heterozygosity. Locations in Finland, on the western edge of the distribution, had the lowest diversities in genomic SNPs and mtDNA, while individuals in the Far East (Sikhote-Alin, Russia) show the highest diversity. These findings fit with a rapid range expansion from the Far East to the west. We found a strong genetic differentiation between Sikhote-Alin and all other populations investigated, which might warrant a revision of their taxonomic classification. The inferred low genetic diversities at the western edge of their distribution are especially worrisome as they are currently experiencing strong population declines and major habitat changes, which can be especially detrimental when standing variation is low. Thus, stressing the need for the revision of the species conservation status.

evolutionary biology↗

bioRxiv2024

Unraveling Genome- and Immunome-wide Genetic Diversity in Jaguars (Panthera onca): Implications for Targeted Conservation

Our study examines the declining Jaguar populations in Central and South America, assessing the impact of habitat loss and fragmentation on genetic diversity and local adaptation. We investigated population structure and immunome variability in 25 jaguars to identify unique genetic diversity for informed, targeted conservation. Our genome-wide analyses revealed three distinct geographic populations corresponding to Central America, South American lowland, and South American highland regions. While the highland population displayed lower overall immunome-wide variability, specific innate (Natural killer cell complex, Toll-like receptor) and adaptive (Major histocompatibility complex-class-II) immune genes crucial for adaptive responses showed promising diversity. Nonetheless, South American highland and Central American jaguars are severely threatened. Therefore, we propose re-evaluating evolutionary significant units to prioritize conservation efforts, preserving crucial genetic and adaptive diversity essential for the species resilience and long-term survival.

genomics↗

bioRxiv2024

The SV40 virus enhancer functions as a somatic hypermutation-targeting element with potential oncogenic activity

Simian virus 40 (SV40) is a monkey virus associated with several types of human cancers. SV40 is most frequently detected in mesotheliomas, brain and bone tumors and lymphomas, but the mechanism for SV40 tumorigenesis in humans is not clear. SV40 relative Merkel cell polyomavirus (MCPyV) causes Merkel cell carcinoma (MCC) in humans by expressing truncated large tumor antigen (LT) caused by APOBEC cytidine deaminase family enzymes induced mutations. AID (activation-induced cytidine deaminase), a member of the APOBEC family, is the initiator of the antibody diversification process known as somatic hypermutation (SHM) and its aberrant expression and targeting is a frequent source of lymphomagenesis. In this study, we investigated whether AID-induced mutations could cause truncation of SV40 LT. We demonstrate that the SV40 enhancer has strong SHM targeting activity in several cell types and that AID-induced mutations accumulate to SV40 LT in B cells and kidney cells and cause truncated LT expression in B cells. Our results argue that the ability of the SV40 enhancer to target SHM to LT is a potential source of LT truncation events in various cell types that could contribute to carcinogenesis.

microbiology↗

bioRxiv2023

Facilitating taxonomy and phylogenetics: An informative and cost-effective protocol integrating long amplicon PCRs and third-generation sequencing

Phylogenetic inference has become a standard technique in integrative taxonomy and systematics, as well as in biogeography and ecology. DNA barcodes are often used for phylogenetic inference, despite being strongly limited due to their low number of informative sites. Also, because current DNA barcodes are based on a fraction of a single, fast-evolving gene, they are highly unsuitable for resolving deeper phylogenetic relationships due to saturation. In recent years, methods that analyse hundreds and thousands of loci at once have improved the resolution of the Tree of Life, but these methods require resources, experience and molecular laboratories that most taxonomists do not have. This paper introduces a PCR-based protocol that produces long amplicons of both slow- and fast-evolving unlinked mitochondrial and nuclear gene regions, which can be sequenced by the affordable and portable ONT MinION platform with low infrastructure or funding requirements. As a proof of concept, we inferred a phylogeny of a sample of 63 spider species from 20 families using our proposed protocol. The results were overall consistent with the results from approaches based on hundreds and thousands of loci, while requiring just a fraction of the cost and labour of such approaches, making our protocol accessible to taxonomists worldwide. HighlightsO_LIDNA barcoding is an invaluable tool for fast and accurate taxonomic classification C_LIO_LIExisting DNA barcodes are still insufficient for obtaining well-supported phylogenies C_LIO_LIWe present a protocol that produces long amplicons of unlinked loci for spiders C_LIO_LIAmplicons are sequenced at very low cost per specimen with ONT MinION C_LIO_LIOur recovered phylogeny is largely consistent with that of high-cost approaches. C_LI

evolutionary biology↗

bioRxiv2023

The unexpected loss of the "hunger hormone" ghrelin in true passerines: A game changer in migration physiology

Migratory birds must accumulate large amounts of fat prior to migration to sustain long flights. In passerines, the small body size limits the amount of energy stores that can be transported and therefore birds undergo cycles of extreme fattening and rapid exhaustion of reserves. Research on these physiological adaptations was rattled by the discovery that birds have lost the main vertebrate regulator of fat deposition, leptin. Recent studies have thus focused on ghrelin, known as the "hunger hormone", a peptide secreted by the gastrointestinal tract to regulate food intake, body mass, and other important functions in vertebrates. Studies on domestic species showed that in birds ghrelin has effects opposite to those described in mammals, such as inhibiting instead of promoting food intake. Furthermore, a series of recent studies have shown that ghrelin administration influences migratory behaviour in passerine birds, suggesting an important role of this hormone in bird migration. However, using comparative genomic analyses we show that ghrelin has been lost in the largest avian taxon Eupasseres, after the basic split from Acanthisitti about 50 million years ago. Eupasserines, also known as True passerines, include all but two of the ca. 10,000 known passerine species. We further found that the ghrelin receptor (growth hormone secretagogue receptor, GHS-R) is still conserved in passerine birds, as indicated by sites under purifying selection and in line with the effects of ghrelin administration. Thus, ghrelin adds to a list of hormones highly conserved in vertebrates that have lost their main functions in specific taxa. The maintenance of a functional receptor system, however, suggests that in eupasserine birds another ligand has replaced ghrelin, perhaps to bypass the feedback system that would hinder large pre-migratory accumulation of subcutaneous fat.

evolutionary biology↗

bioRxiv2023

Evolution of chemosensory and detoxification gene families across herbivorous Drosophilidae

Herbivorous insects are exceptionally diverse, accounting for a quarter of all known eukaryotic species, but the genetic basis of adaptations that enabled this dietary transition remains poorly understood. Many studies have suggested that expansions and contractions of chemosensory and detoxification gene families - genes directly mediating interactions with plant chemical defenses - underlie successful plant colonization. However, this hypothesis has been challenging to test because the origins of herbivory in many lineages are ancient (>150 million years ago [mya]), obscuring genomic evolutionary patterns. Here, we characterized chemosensory and detoxification gene family evolution across Scaptomyza, a genus nested within Drosophila that includes a recently derived (<15 mya) herbivore lineage of mustard (Brassicales) specialists and carnation (Caryophyllaceae) specialists, and several non-herbivorous species. Comparative genomic analyses revealed that herbivorous Scaptomyza have among the smallest chemosensory and detoxification gene repertoires across 12 drosophilid species surveyed. Rates of gene turnover averaged across the herbivore clade were significantly higher than background rates in over half of the surveyed gene families. However, gene turnover was more limited along the ancestral herbivore branch, with only gustatory receptors and odorant binding proteins experiencing strong losses. The genes most significantly impacted by gene loss, duplication, or changes in selective constraint were those involved in detecting compounds associated with feeding on plants (bitter or electrophilic phytotoxins) or their ancestral diet (yeast and fruit volatiles). These results provide insight into the molecular and evolutionary mechanisms of plant-feeding adaptations and highlight strong gene candidates that have also been linked to other dietary transitions in Drosophila.

evolutionary biology↗

bioRxiv2022

A chromosome-scale high-contiguity genome assembly of the threatened cheetah (Acinonyx jubatus)

The cheetah (Acinonyx jubatus, SCHREBER 1775) is a large felid and is considered the fastest land animal. Historically, it inhabited open grassland across Africa, the Arabian Peninsula, and southwestern Asia; however, only small and fragmented populations remain today. Here, we present a de novo genome assembly of the cheetah based on PacBio continuous long reads and Hi-C proximity ligation data. The final assembly (VMU_Ajub_asm_v1.0) has a total length of 2.38 Gb, of which 99.7% are anchored into the expected 19 chromosome-scale scaffolds. The contig and scaffold N50 values of 96.8 Mb and 144.4 Mb, respectively, a BUSCO completeness of 95.4% and a k-mer completeness of 98.4%, emphasize the high quality of the assembly. Furthermore, annotation of the assembly identified 23,622 genes and a repeat content of 40.4%. This new highly contiguous and chromosome-scale assembly will greatly benefit conservation and evolutionary genomic analyses and will be a valuable resource, e.g., to gain a detailed understanding of the function and diversity of immune response genes in felids.

genomics↗

bioRxiv2021

Rapid ecological and evolutionary divergence during a poleward range expansion

In response to climate change, a northward range expansion has been observed in many species. The wasp spider, Argiope bruennichi, has expanded from its historic range in the Mediterranean ("core"), now reaching as far as the Baltic States and Scandinavia ("edge"), even faster than the pace of climate change. We explored life history traits, adult phenotypes, offspring cold tolerance, and genomic patterns across the European range of A. bruennichi, and found origin-, environment- and life stage-specific responses to the cold northern climate. Wasp spiders have shifted their phenology at the edge, with females maturing earlier and at a smaller size, but maintaining similar pigmentation, clutch sizes, and hatching success compared to the core region. Using a reciprocal common garden experiment on overwintering offspring from the core and edge, we found evidence for genetic adaptation and considerable phenotypic plasticity. Overwintering survival was lower under the cold winter treatment for spiderlings from both origins. However, the edge-origin spiderlings that survived the winter had lower lethal temperatures and enhanced supercooling ability with reduced phenotypic plasticity in supercooling points compared to core spiderlings, while the chill coma recovery time was similar. Metabolomic analysis revealed accumulations of amino acids and myo-inositol in the cold winter treatment, particularly in spiderlings from the edge population, suggesting a role of these metabolites in improving cold tolerance. Genotype-environment tests showed strong genetic association across the genome to seasonality and minimum winter temperature. The population genomic analysis across the European range splits A. bruennichi into two distinct genetic clusters through the center of Germany, which roughly aligns with turnover from an oceanic to continental climate zone, complementing the genotype-environment test results. Overall, our study highlights the importance of integrating data on phenological shifts, changes in life-history, and life stage-specific phenotypic plasticity and genetic adaptation to understand the impacts of range expansions and shifts. The nuanced processes of acclimation and adaptation we uncovered advocate for holistic investigations of evolutionary fitness and fitness-related traits in the context of organismal responses to novel and changing environments.

ecology↗

bioRxiv2020

Ecological specialisation and evolutionary reticulation in extant Hyaenidae

During the Miocene, Hyaenidae was a highly diverse family of Carnivora that has since been severely reduced to four extant genera, each of which contains only a single species. These species include the bone-cracking spotted, striped, and brown hyenas, and the specialised insectivorous aardwolf. Previous genome studies have analysed the evolutionary histories of the spotted and brown hyenas, but little is known about the remaining two species. Moreover, the genomic underpinnings of scavenging and insectivory, defining traits of the extant species, remain elusive. To tackle these questions, we generated an aardwolf genome and analysed it together with those from the other three species. We provide new insights into the evolutionary relationships between the species, the genomic underpinnings of their scavenging and insectivorous lifestyles, and their respective genetic diversities and demographic histories. High levels of phylogenetic discordance within the family suggest gene flow between the aardwolf lineage and the ancestral brown/striped hyena lineage. Genes related to immunity and digestion in the bone-cracking hyenas and craniofacial development in the aardwolf showed the strongest signals of selection in their respective lineages, suggesting putative key adaptations to carrion or termite feeding. We also found a family-wide expansion in olfactory receptor genes suggesting that an acute sense of smell was a key early adaptation for the Hyaenidae family. Finally, we report very low levels of genetic diversity within the brown and striped hyenas despite no signs of inbreeding, which we putatively link to their similarly slow decline in Neover the last [~]2 million years. We found much higher levels of genetic diversity in both the spotted hyena and aardwolf and more stable population sizes through time. Taken together, these findings highlight how ecological specialisation can impact the evolutionary history, demographics, and adaptive genetic changes of a lineage.

evolutionary biology↗

bioRxiv2020

Chromosome-level genome assembly of a benthic associated Syngnathiformes species: the common dragonet, Callionymus lyra

BackgroundThe common dragonet, Callionymus lyra, is one of three Callionymus species inhabiting the North Sea. All three species show strong sexual dimorphism. The males show strong morphological differentiation, e.g., species-specific colouration and size relations, while the females of different species have few distinguishing characters. Callionymus belongs to the benthic associated clade of the order Syngnathiformes. The benthic associated clade so far is not represented by genome data and serves as an important outgroup to understand the morphological transformation in long-snouted syngnatiforms such as seahorses and pipefishes. FindingsHere, we present the chromosome-level genome assembly of C. lyra. We applied Oxford Nanopore Technologies long-read sequencing, short-read DNBseq, and proximity-ligation-based scaffolding to generate a high-quality genome assembly. The resulting assembly has a contig N50 of 2.2 Mbp, a scaffold N50 of 26.7 Mbp. The total assembly length is 568.7 Mbp, of which over 538 Mbp were scaffolded into 19 chromosome-length scaffolds. The identification of 94.5% of complete BUSCO genes indicates high assembly completeness. Additionally, we sequenced and assembled a multi-tissue transcriptome with a total length of 255.5 Mbp that was used to aid the annotation of the genome assembly. The annotation resulted in 19,849 annotated transcripts and identified a repeat content of 27.66%. ConclusionsThe chromosome-level assembly of C. lyra provides a high-quality reference genome for future population genomic, phylogenomic, and phylogeographic analyses.

genomics↗

bioRxiv2020

Chromosome-level reference genome of the European wasp spider Argiope bruennichi: a resource for studies on range expansion and evolutionary adaptation

BackgroundArgiope bruennichi, the European wasp spider, has been studied intensively as to sexual selection, chemical communication, and the dynamics of rapid range expansion at a behavioral and genetic level. However, the lack of a reference genome has limited insights into the genetic basis for these phenomena. Therefore, we assembled a high-quality chromosome-level reference genome of the European wasp spider as a tool for more in-depth future studies. FindingsWe generated, de novo, a 1.67Gb genome assembly of A. bruennichi using 21.5X PacBio sequencing, polished with 30X Illumina paired-end sequencing data, and proximity ligation (Hi-C) based scaffolding. This resulted in an N50 scaffold size of 124Mb and an N50 contig size of 288kb. We found 98.4% of the genome to be contained in 13 scaffolds, fitting the expected number of chromosomes (n = 13). Analyses showed the presence of 91.1% of complete arthropod BUSCOs, indicating a high quality of the assembly. ConclusionsWe present the first chromosome-level genome assembly in the class Arachnida. With this genomic resource, we open the door for more precise and informative studies on evolution and adaptation in A. bruennichi, as well as on several interesting topics in Arachnids, such as the genomic architecture of traits, whole genome duplication and the genomic mechanisms behind silk and venom evolution.

genomics↗