We present a genome assembly from a specimen of Trididemnum nubilum (ascidian; Chordata; Ascidiacea; Aplousobranchia; Didemnidae). The genome sequence has a total length of 1 050.96 megabases. Most of the assembly (95.66%) is scaffolded into 22 chromosomal pseudomolecules. The mitochondrial genome has also been assembled, with a length of 13.39 kilobases. From the metagenome data, we recovered 14 bins, of which 7 were high-quality MAGs. While the host ascidian always harbours brown cyanobacterial cells in its tunic, the metagenomic bins include a single cyanobacterial bin. Sequences from the ascidian genome and microbial metagenomes provide an essential basis for understanding this obligate photosymbiosis system.
Hirose et al. (Fri,) studied this question.