Chromosome-level genome assembly of the brown alga Undaria pinnatifida using PacBio and Hi-C technologies

Undaria pinnatifida is an important economic kelp species in East Asia. In recent decades it has drawn increasing attention due to its worldwide spread as an invasive species. Lack of genome sequence hinders crucial fundamental researches in this alga. Herein, we present the whole genome sequence of a male gametophyte of U. pinnatifida, the first reference genome of the family Alariaceae. The genome, which was assembled based on the clean data produced by the Pacific Biosciences sequencing platform, was 511.0 Mb with contig N50 length of 1.7 Mb. We then assembled the contigs into chromosome-level scaffolds with an N50 length of 16.5 Mb using the high-throughput chromosome conformation capture (Hi-C) technology. In total 502.8 Mb genomic sequences were located on 30 chromosomes, accounting for 98.4% of the whole assembled length. A total of 12,402 protein-coding genes were annotated in the reference genome. This chromosome-level genome will provide valuable information for molecular biological studies in U. pinnatifida and comparative genomic studies with other brown algae.