Transcriptomic analyses of gastrointestinal function in the “dwarf” and “medium” forms of Sthenoteuthis oualaniensis during sexual maturation

Sthenoteuthis oualaniensis (SA) is an important squid species in the South China Sea. Based on SA samples collected in 2016, SA was divided into the “dwarf” form (DF) and “medium” form (MF). To understand the changes in gastrointestinal function in SA during sexual maturation, we undertook transcriptomic analyses of the stomach and intestine tissues of the DF and MF of SA using the deep-sequencing platform Illumina HiSeq™. We exploited a high-throughput method to delineate differentially expressed genes (DEGs) in the DF and MF of SA. A total of 135,464 unigenes (68627 unigenes of the DG and 66837 unigenes of the MF) were generated. We identified 7965 and 4051 relative DEGs in the intestine and stomach tissue of the mature DF of SA compared with those of the immature DF of SA; and 22138 and 18460 DEGs in the intestine and stomach of the mature MF of SA compared with those of the immature MF of SA. Functional categorization and pathway analyses of these DEGs with regard to the metabolism of differentially expressed genes were noted. This work is the first to identify a set of genes associated with gastrointestinal function during the sexual maturation of SA. Overall design: Intestinal and stomach tissues were sampled from three mature dwarf form (DF) SAs, three immature DF SAs, three mature medium form (MF) SAs, and three immature MF SAs, respectively.