TodoFirGene: Developing Transcriptome Resources for Genetic Analysis of Abies sachalinensis

Todo-matsu (Abies sachalinensis) is one of the most important forestry species in Hokkaido, Japan and is distributed from near sea level to the alpine zone. Due to its wide spatial distribution, the species adapts to its environment, displaying phenotypes of ecological relevance. In order to identify candidate genes under natural selection, we collected the transcriptome from the female and male flower, leaf and inner bark. De novo assembly with 34.7 Gb of sequencing reads produced 158,542 transcripts from 69,618 loci, whose estimated coverage reached 95.6% of conserved eukaryotic genes. Homology searches against publicly available databases identified 134,190 (84.6%) transcripts with at least one hit. In total, 28,944 simple sequence repeats (SSRs) and 80,758 single nucleotide variants (SNVs) were detected from 23,570 (14.9%) and 25,366 (16.0%) transcripts, which were valuable for use in genetic analysis of the species. All the annotations were included in a relational database, TodoFirGene, which provides an interface for various queries and homology search, and can be accessed at http://plantomics.mind.meiji.ac.jp/todomatsu/. This database hosts not only the A. sachalinensis transcriptome but also links to the proteomes of 13 other species, allowing a comparative genomic study of plant species.