White band disease (WBD) has caused unprecedented declines in the CaribbeanAcroporacorals, which are now listed as critically endangered species. Highly disease-resistantAcropora cervicornisgenotypes exist, but the genetic underpinnings of disease resistance are not understood. Using transmission experiments, a newly assembled genome, and whole-genome resequencing of 76A. cervicornisgenotypes from Florida and Panama, we identified 10 genomic regions and 73 single-nucleotide polymorphisms that are associated with disease resistance and that include functional protein-coding changes in four genes involved in coral immunity and pathogen detection. Polygenic scores calculated from 10 genomic loci indicate that genetic screens can detect disease resistance in wild and nursery stocks ofA. cervicornisacross the Caribbean.
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Whole genome assembly and annotation of the endangered Caribbean coral Acropora cervicornis
Abstract Coral species in the genus Acropora are key ecological components of coral reefs worldwide and represent the most diverse genus of scleractinian corals. While key species of Indo-Pacific Acropora have annotated genomes, no annotated genome has been published for either of the two species of Caribbean Acropora. Here we present the first fully annotated genome of the endangered Caribbean staghorn coral, Acropora cervicornis. We assembled and annotated this genome using high-fidelity nanopore long-read sequencing with gene annotations validated with mRNA sequencing. The assembled genome size is 318 Mb, with 28,059 validated genes. Comparative genomic analyses with other Acropora revealed unique features in A. cervicornis, including contractions in immune pathways and expansions in signaling pathways. Phylogenetic analysis confirms previous findings showing that A. cervicornis diverged from Indo-Pacific relatives around 41 million years ago, with the closure of the western Tethys Sea, prior to the primary radiation of Indo-Pacific Acropora. This new A. cervicornis genome enriches our understanding of the speciose Acropora and addresses evolutionary inquiries concerning speciation and hybridization in this diverse clade.
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- Award ID(s):
- 1924145
- PAR ID:
- 10534391
- Editor(s):
- Vogel, K
- Publisher / Repository:
- Oxford Press
- Date Published:
- Journal Name:
- G3: Genes, Genomes, Genetics
- Volume:
- 13
- Issue:
- 12
- ISSN:
- 2160-1836
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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