RNA sequencing, de novo assembly, and functional annotation of an endangered Nymphalid butterfly, Fabriciana nerippeFelder, 1862

Abstract

Grassland butterflies are considered representative indicators of biodiversity and ecosystem health. Their dramatic decline caused by habitat destruction, intensifying agriculture and global warming has prompted concern for conservation. While ecological indices of butterflies have been documented, there is a lack of genomic resources relative to the biological importance of this group. Here, we report, first whole-transcriptomic resource for Fabriciana nerippe, a brush-footed butterfly member that is endangered in Korea. Approximately, 241.3 million clean reads were obtained from paired-end Illumina sequencing of adult whole-body RNA. The de novo assembly resulted in 114405 unigenes with length ranging from 133 to 33218bp. We found 41868 assembled unigenes homologous to sequences in locally curated PANM-DB (Protostome DB). We assigned gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology terms to 18085 and 5779 unigenes, respectively. InterProScan predicted 6691 protein domains for the assembled unigene sequences, with the reverse transcriptase and zinc finger domains found to be the most predominant. A total of 315282 simple sequence repeats (SSRs) were identified from the assembled unigenes, when considering dinucleotide to octanucleotide repeats with a minimum of three repeat units. AT/AT, AAT/ATT, and AAAT/ATTT represented the most prominent SSR repeat types in the transcriptome. The unigene annotation profile and microsatellites generated in the study can serve as a reference resource for closely related species and gene functional analysis studies. Our data can be utilized to study ecological drift and loss of the species, consequently leading to better protection of the population.