De novo transcriptome assembly of the digitate morphotype of Briareum asbestinum (Octocorallia: Alcyonacea) from the southwest shelf of Puerto Rico.

Octocorals have now become the most visually dominant metazoan benthic taxa of most Caribbean reefs, following the precipitous decline of scleractinian corals. Yet taxonomic issues because of their extensive phenotypic plasticity are still abound. Briareum asbestinum one of the iconic octocorals of the shallow Caribbean coral reefs exhibits a biform morphology, the digitate and the encrusting one. The taxonomic status of each form has not been clarified, yet. Until recently, there were few genetic resources for non-model metazoans, however, affordable high-throughput DNA sequencing has removed this hindrance. We present the first transcriptome of the digitate form of Briareum asbestinum from southwest Puerto Rico. We used paired-end sequencing (Illumina NextSeq 500), with a total yield of 159,754,702 raw reads. De novo assembly was performed utilizing a multi-assembler approach generating 371,554 biologically true, non-redundant transcripts. Open reading frame analysis identified 102,839 putative ORFs of which 78,607 were with annotations. BUSCO analysis indicated a total of 96.4% complete orthologous genes from the metazoan dataset. The assembly presented here serves as an important new genomic reference for the Briareum genus that will facilitate future population and phylogenetic studies aiming to better understand the molecular basis of phenotypic plasticity exhibited throughout the genus.

De novo transcriptome assembly of the coral Agaricia lamarcki (Lamarck's sheet coral) from mesophotic depth in southwest Puerto Rico.

The plating coral, Agaricia lamarcki is a widely distributed species inhabiting reefs across the Caribbean basin and Florida. This species is of interest since it is considered a depth-generalist, found from 10 to 70 m. Given the scope of contemporary studies on this coral's population dynamics and physiology, as well as, the potential of mesophotic reefs to be refuge habitats for deteriorated shallow water reefs, we present the first de novo transcriptome assembly of an important mesophotic coral. Using next-generation paired-end sequencing (Illumina Hiseq4000; 2 × 150 bp), we obtained a total of 82,506,058 raw reads. The novel transcriptome assembly strategy included the recently developed National Center for Genome Analysis Support de novo transcriptome assembly pipeline. Assembly produced a total of 101,322 biologically true, non-redundant transcripts with an average contig length of 959 and N50 of 1830. EvidentialGene and TransDecoder were used to identify open reading frames (ORFs) with homology insight provided by the UniProtKb and PFAM databases. ORF prediction resulted in 38,517 putative ORFs of which 12,107 ORFs were annotated as genes dealing with molecular function, 1266 with biological processes and 416 with cellular components.