Reef-building corals are integral ecosystem engineers of tropical reefs but face threats from climate change. Investigating genetic, epigenetic, and environmental factors influencing their adaptation is critical. Genomic resources are essential for understanding coral biology and guiding conservation efforts. However, genomes of the coral genus Acropora are limited to highly-studied species. Here, we present the assembly and annotation of the genome and DNA methylome of Acropora pulchra from Mo’orea, French Polynesia. Using long-read PacBio HiFi and Illumina RNASeq, we generated the most complete Acropora genome to date (BUSCO completeness of 96.7% metazoan genes). The assembly size is 518 Mbp, with 174 scaffolds, and a scaffold N50 of 17 Mbp. We predicted 40,518 protein-coding genes and 16.74% of the genome in repeats. DNA methylation in the CpG context is 14.6%. This assembly of the A. pulchra genome and DNA methylome will support studies of coastal corals in French Polynesia, aiding conservation and comparative studies of Acropora and cnidarians.
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Chromosomal-level reference genome assembly of muskox (Ovibos moschatus) from Banks Island in the Canadian Arctic, a resource for conservation genomics
Abstract The muskox (Ovibos moschatus), an integral component and iconic symbol of arctic biocultural diversity, is under threat by rapid environmental disruptions from climate change. We report a chromosomal-level haploid genome assembly of a muskox from Banks Island in the Canadian Arctic Archipelago. The assembly has a contig N50 of 44.7 Mbp, a scaffold N50 of 112.3 Mbp, a complete representation (100%) of the BUSCO v5.2.2 set of 9225 mammalian marker genes and is anchored to the 24 chromosomes of the muskox. Tabulation of heterozygous single nucleotide variants in our specimen revealed a very low level of genetic diversity, which is consistent with recent reports of the muskox having the lowest genome-wide heterozygosity among the ungulates. While muskox populations are currently showing no overt signs of inbreeding depression, environmental disruptions are expected to strain the genomic resilience of the species. One notable impact of rapid climate change in the Arctic is the spread of emerging infectious and parasitic diseases in the muskox, as exemplified by the range expansion of muskox lungworms, and the recent fatal outbreaks ofErysipelothrix rhusiopathiae, a pathogen normally associated with domestic swine and poultry. As a genomics resource for conservation management of the muskox against existing and emerging disease modalities, we annotated the genes of the major histocompatibility complex on chromosome 2 and performed an initial assessment of the genetic diversity of this complex. This resource is further supported by the annotation of the principal genes of the innate immunity system, genes that are rapidly evolving and under positive selection in the muskox, genes associated with environmental adaptations, and the genes associated with socioeconomic benefits for Arctic communities such as wool (qiviut) attributes. These annotations will benefit muskox management and conservation.
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- Award ID(s):
- 2127271
- PAR ID:
- 10553095
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Reef-building corals are integral ecosystem engineers in tropical coral reefs worldwide but are increasingly threatened by climate change and rising ocean temperatures. Consequently, there is an urgency to identify genetic, epigenetic, and environmental factors, and how they interact, for species acclimatization and adaptation. The availability of genomic resources is essential for understanding the biology of these organisms and informing future research needs for management and and conservation. The highly diverse coral genusAcroporaboasts the largest number of high-quality coral genomes, but these remain limited to a few geographic regions and highly studied species. Here we present the assembly and annotation of the genome and DNA methylome ofAcropora pulchrafrom Mo’orea, French Polynesia. The genome assembly was created from a combination of long-read PacBio HiFi data, from which DNA methylation data were also called and quantified, and additional Illumina RNASeq data forab initiogene predictions. The work presented here resulted in the most completeAcroporagenome to date, with a BUSCO completeness of 96.7% metazoan genes. The assembly size is 518 Mbp, with 174 scaffolds, and a scaffold N50 of 17 Mbp. Structural and functional annotation resulted in the prediction of a total of 40,518 protein-coding genes, and 16.74% of the genome in repeats. DNA methylation in the CpG context was 14.6% and predominantly found in flanking and gene body regions (61.7%). This reference assembly of theA. pulchragenome and DNA methylome will provide the capacity for further mechanistic studies of a common coastal coral in French Polynesia of great relevance for restoration and improve our capacity for comparative genomics inAcroporaand cnidarians more broadly.more » « less
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Abstract White clover (Trifolium repens L.; Fabaceae) is an important forage and cover crop in agricultural pastures around the world and is increasingly used in evolutionary ecology and genetics to understand the genetic basis of adaptation. Historically, improvements in white clover breeding practices and assessments of genetic variation in nature have been hampered by a lack of high-quality genomic resources for this species, owing in part to its high heterozygosity and allotetraploid hybrid origin. Here, we use PacBio HiFi and chromosome conformation capture (Omni-C) technologies to generate a chromosome-level, haplotype-resolved genome assembly for white clover totaling 998 Mbp (scaffold N50 = 59.3 Mbp) and 1 Gbp (scaffold N50 = 58.6 Mbp) for haplotypes 1 and 2, respectively, with each haplotype arranged into 16 chromosomes (8 per subgenome). We additionally provide a functionally annotated haploid mapping assembly (968 Mbp, scaffold N50 = 59.9 Mbp), which drastically improves on the existing reference assembly in both contiguity and assembly accuracy. We annotated 78,174 protein-coding genes, resulting in protein BUSCO completeness scores of 99.6% and 99.3% against the embryophyta_odb10 and fabales_odb10 lineage datasets, respectively.more » « less
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