The scaffold-level genome sequence of an encrusting sponge, Halisarca caerulea Vacelet & Donadey, 1987, and its associated microbial metagenome sequences

Abstract

We present a scaffold-level genome assembly from a Halisarca caerulea specimen (encrusting sponge; Porifera; Demospongiae; Chondrillida; Halisarcidae). The genome sequence is 195.70 megabases in span. The mitochondrial genome has also been assembled and is 19.15 kilobases in length. Gene annotation of this assembly on Ensembl identified 26,722 protein-coding genes. The metagenome of the specimen was also assembled and four binned bacterial genomes related to the relevant sponge symbiont clades Alphaproteobacteria bacterium GM7ARS4 and Gammaproteobacteria bacterium AqS2 ((Tethybacterales) were identified.

Keywords: Chondrillida; metagenome assembly; Halisarca caerulea; chromosomal; encrusting sponge; genome sequence.

Figure 1.. Morphological variations of Halisarca caerulea on the reefs of Curaçao.

( A) Violet and purple colour morph next to each other. ( B) Close up of star-shape canal system surrounding oscula. ( C) Shallow water (~10 m) specimen concealed under a coral overhang. ( D) Deep water specimen growing openly on the reef at 35 m depth. White scale bar in the lower right corner of each panel represents 2 cm.

Figure 2.. Genome assembly of Halisarca caerulea, odHalCaeu1.1: metrics.

The BlobToolKit snail plot shows N50 metrics and BUSCO gene completeness. The main plot is divided into 1,000 size-ordered bins around the circumference with each bin representing 0.1% of the 195,692,738 bp assembly. The distribution of sequence lengths is shown in dark grey with the plot radius scaled to the longest sequence present in the assembly (14,164,103 bp, shown in red). Orange and pale-orange arcs show the N50 and N90 sequence lengths (2,795,200 and 251,000 bp), respectively. The pale grey spiral shows the cumulative sequence count on a log scale with white scale lines showing successive orders of magnitude. The blue and pale-blue area around the outside of the plot shows the distribution of GC, AT and N percentages in the same bins as the inner plot. A summary of complete, fragmented, duplicated and missing BUSCO genes in the metazoa_odb10 set is shown in the top right. An interactive version of this figure is available at https://blobtoolkit.genomehubs.org/view/Halisarca%20caerulea/dataset/CAUJGJ01/snail.

Figure 3.. Genome assembly of Halisarca caerulea, odHalCaeu1.1: BlobToolKit GC-coverage plot.

Scaffolds are coloured by phylum. Circles are sized in proportion to scaffold length. Histograms show the distribution of scaffold length sum along each axis. An interactive version of this figure is available at https://blobtoolkit.genomehubs.org/view/Halisarca%20caerulea/dataset/CAUJGJ01/blob.

Figure 4.. Genome assembly of Halisarca caerulea, odHalCaeu1.1: BlobToolKit cumulative sequence plot.

The grey line shows cumulative length for all scaffolds. Coloured lines show cumulative lengths of scaffolds assigned to each phylum using the buscogenes taxrule. An interactive version of this figure is available at https://blobtoolkit.genomehubs.org/view/Halisarca%20caerulea/dataset/CAUJGJ01/cumulative.

Figure 5.. Blob plot of base coverage in mapped against GC proportion for sequences in the Halisarca caerulea metagenome.

Binned contigs are coloured by family. Circles are sized in proportion to sequence length on a square root scale, ranging from 2,140 to 8,133,556. Histograms show the distribution of sequence length sum along each axis.