Transcriptome-based discovery of pathways and genes related to reproduction of the black tiger shrimp (Penaeus monodon).

The black tiger shrimp (Penaeus monodon) is an aquatic animal with considerable economic importance. Poor reproductive maturation in captivity impedes sustainable aquaculture production of this species. This study aims to provide transcriptomic information on reproductive organs using 454 pyrosequencing technology. The transcriptome analysis of ovaries and testes revealed 41,136 transcripts with 20,192 contigs. We found novel sets of transcripts completing several important reproductive pathways such as gonadotropin-releasing hormone (GnRH) signaling and progesterone-mediated oocyte maturation. In addition, we found transcripts encoding for receptors crucial for initiation of the maturation process, such as GnRH receptor (GnRHR), voltage-dependent calcium channel L type alpha-1C (CACNA1C) and epidermal growth factor receptor (EGFR). Moreover, we found a putative novel vigillin encoding for an estrogen-induced polysome-associated protein, which has not been reported in penaeid shrimp. These results suggest that the regulatory mechanism of the pathways important to reproductive maturation might be similar to those in the vertebrate. The obtained data will consequently accelerate the study of reproductive biology of this important species to ensure a sustainable shrimp farming industry.