Genome assembly and annotation of Acropora pulchra from Mo'orea French Polynesia

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 genus Acropora boasts 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 of Acropora pulchra from Moorea, 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 for ab initio gene predictions. The work presented here resulted in the most complete Acropora genome 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 the A. pulchra genome 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 in Acropora and cnidarians more broadly.