De Novo transcriptome assembly and annotation of the wild service tree Sorbus torminalis (L.) Crantz

The wild service tree, Sorbus torminalis (L.) Crantz, is a sub-Mediterranean forest tree species native to Europe, Asia Minor, Caucasus and north-western Africa. Despite its ecological and societal importance, publicly available molecular resources for this species are scarce, limited to the chloroplast genome. Within the European Project FORGENIUS (Improving access to FORest GENetic resources Information and services for end-Users, Grant Agreement ID: 862221) we assembled the transcriptome of the wild service tree with the aim to use it as reference to develop new genetic markers and perform a large-scale population genetics study in this species.

An RNA-seq library was generated from pooled RNA extracted from four different tissues (young leaves, mature leaves, stems and roots) of a single S. torminalis sapling and sequenced on the Illumina HiSeq 2500 platform. This dataset was used to produce and annotate the first transcriptome assembly for S. torminalis, paving the way for future genomic research and applications in this species. For example, this study will facilitate the development of molecular markers such as SSRs and SNPs, useful for genetic studies, breeding programs, and conservation efforts and will serve as a reference for future differential expression studies, providing a deeper understanding of the species' biology.