Expression Patterns of Atlantic Sturgeon (Acipenser oxyrinchus) During Embryonic Development.

Abstract

During teleost ontogeny the larval and embryonic stages are key stages, since failure during this period of tissue differentiation may cause malformations, developmental delays, poor growth, and massive mortalities. Despite the rapid advances in sequencing technologies, the molecular backgrounds of the development of economically important but endangered fish species like the Atlantic sturgeon (Acipenser oxyrinchus) have not yet been thoroughly investigated. The current study examines the differential expression of transcripts involved in embryonic development of the Atlantic sturgeon. Addressing this goal, a reference transcriptome comprising eight stages was generated using an Illumina HiSequation 2500 platform. The constructed de novo assembly counted to 441,092 unfiltered and 179,564 filtered transcripts. Subsequently, the expression profile of four developmental stages ranging from early (gastrula) to late stages of prelarval development [2 d posthatching (dph)] were investigated applying an Illumina MiSeq platform. Differential expression analysis revealed distinct expression patterns among stages, especially between the two early and the two later stages. Transcripts upregulated at the two early stages were mainly enriched in transcripts linked to developmental processes, while transcripts expressed at the last two stages were mainly enriched in transcripts important to muscle contraction. Furthermore, important stage-specific expression has been detected for the hatching stage with transcripts enriched in molecule transport, and for the 2 dph stage with transcripts enriched in visual perception and lipid digestion. Our investigation represents a significant contribution to the understanding of Atlantic sturgeon embryonic development, and transcript characterization along with the differential expression results will significantly contribute to sturgeon research and aquaculture.