Transcriptome analyses of female black tiger shrimps (Penaeus monodon) for reproductive trait using RNA-sequencing approach

The black tiger shrimp (Penaeus monodon) is the widely cultured aquaculture species in Vietnam and worldwide. Production of P. monodon postlarvae still relies on the wild broodstock due to their higher fecundity and larval quality in comparison with the domesticated broodstock. Therefore, the current study applied an RNA-sequencing approach by the Illumina platform to generate the transcriptomic resources for the wild and domesticated females at the previtellogenic stage of ovaries (stage 0). Total clean reads were 20,977,708 for the wild female and 31,185,197 for the domesticated female. De novoassembly was employed to generate 35,870 contigs with an average length of 1,018 bp and N50 length of 1,488 bp. The ratios of contigs possessing significant similarity through annotation across seven databases ranged from 19.74 to 47.77%. Top hit species from BLASTx searches included Hyalella azteca, Cryptotermes secundus, Zootermopsis nevadensis, followed by Penaeus sp.. We identified a total of 5,788 differentially expressed transcripts between the ovaries of wild and domesticated shrimps. The differentially expressed transcripts were further enriched according to the classification terms of Gene Ontology (GO). Results of GO enrichment analysis in the wild female indicated that many genes such as hemolymph clottable, peritrophin, ecdysteroid were up-regulated while the following genes, including serine protease, alpha-L-fucosidase-like, actin, catenin alpha were down-regulated. The current study provides more transcriptomic resources for the reproductive trait in P. monodon. These resources are potentially applied for the improvement of reproduction in the domesticated shrimp.