Supporting data for "Chromosomal-level assembly of the mustache toad genome using third-generation DNA sequencing and Hi-C analysis"

The mustache toad, Vibrissaphora ailaonica, is an endemic species to China belonging to the Megophryidae family. Like other mustache toad species, V. ailaonica males temporarily develop keratinized nuptial spines on their upper jaw during each breeding season that fall off when the breeding season ends, which probably reversed the sexual size dimorphism with males being larger than females. To investigate the genetic mechanism of the repeatedly developed keratinized spines, a high-quality reference genome of mustache toad would be a valuable resource. For genome construction, we generated 225 Gb of short reads and 277 Gb of long reads using Illumina and Pacific Biosciences (PacBio) sequencing, respectively. The sequencing data were assembled into a 3.53 Gb genome assembly with a contig N50 length of 821 Kb. Additionally, we applied Hi-C technology to identify contacts among contigs, then assembled contigs into scaffolds and identified a genome assembly with 13 chromosomes and a scaffold N50 length of 412.42 Mb. Based on the 26,227 protein-coding genes annotated in the genome, we analyzed the phylogenetic relationships of the mustache toad with other chordate species. Results showed that the mustache toad has a relatively higher evolutionary rate and separated from the marine toad, bull frog, and Tibetan frog ancestor 206.1 million years ago. Furthermore, we identified 201 expanded gene families in the mustache toad, which were mainly enriched in immune pathway, keratin filament, and metabolic processes. Using Illumina, PacBio, and Hi-C technologies, we constructed the first high-quality chromosomal-level mustache toad genome. This work not only offers a valuable reference genome for functional studies of mustache toad traits, but also provides important chromosome information for wider genome comparisons.