A multi-tissue de novo transcriptome assembly and relative gene expression of the vulnerable freshwater salmonid Thymallus ligericus

Abstract

Freshwater ecosystems are among the most endangered worldwide. While numerous taxa are on the verge of extinction as a result of global changes and direct or indirect anthropogenic activity, genomic and transcriptomic resources are a key tool to comprehend species adaptability and serve as the foundation for conservation initiatives. The Loire grayling, Thymallus ligericus, is a freshwater European salmonid endemic to the upper Loire River basin. It comprises fragmented populations dispersed over a small area and has been identified as a vulnerable species. Here, we provide a multi-tissue de novo transcriptome assembly of T. ligericus. The final assembly, with a contig N50 of 1,221 and Benchmarking Universal Single-Copy Orthologs (BUSCO) scores above 94%, is made accessible, along with structural and functional annotations and relative gene expression of five tissues. This is the first transcriptomic resource for this species, and it will serve as the foundation for future research on a species that is increasingly exposed to environmental stressors.