Identification of genes that potentially affect social dominance hierarchy in adult male giant freshwater prawns (Macrobrachium rosenbergii)

The giant freshwater prawn (GFP) or Macrobrachium rosenbergii is one of the most important freshwater aquaculture crustaceans worldwide. An enduring problem with the improvement of this species in culture is the social dominance hierarchy that is manifested in male morphotypes where a few fast growing males (blue claw) individuals inhibit the growth of subdominant males. Here, we applied a transcriptomics approach to identify genes that contribute to expression of dominant phenotypes. Six different GFP tissues (abdominal muscle, hepatopancreas, stomach, claw, eyestalk and testis/ovary) were dissected for RNA extraction to prepare cDNA libraries for sequencing in Illumina NextSeq 500 platform. Illumina sequence reads were assembled and annotated for identifying candidate genes. This dataset currently provides the most comprehensive transcriptome data set available for GFP (147,507,623 reads assembled into 30,522 annotated contigs). 40 candidate genes were identified that could potentially play a role in determining adult male morphotype. Candidate genes identified include; Red pigment concentrating hormone (RPCH), Adipokinetic hormone receptor, Pigment dispersing hormone precursor (PDH), Pheromone and odorant, Visual pigment like receptor, Opsin, Glycoprotein 93 and Lola protein isoform a. The genes identified here provide a resource for understanding adult male morphotype development and the hierarchical dominance system in adult male GFP. In the future this information can be applied potentially to manipulate male morphotype frequencies in culture to bias adult male phenotypic ratios to improve overall productivity in practical genetic improvement programs.