The swimming crab, Portunus trituberculatus, is an important marine animal and is widely cultured in China. In the present study, suppression subtractive hybridization was applied to identify the differentially expressed genes in the ovaries of mature and immature P. trituberculatus. One hundred and seventy six expressed sequence tag (ESTs) were identified, of which 100 were down-regulated, and 76 up-regulated. BLAST analysis identified 51 unigenes, of which 27 were down-regulated, and 24 up-regulated.
Challenged by the low salinity, 4 parts per thousand (4 ppt), for 72h, the survivals of swimming crabs (Portunus trituberculatus) were collected as the screened group (SG, tolerant to low salinity). Aiming at identifying the mechanism of low salinity tolerance, quantitative real-time PCR was employed to investigate the expression profiles of 4 HSP genes (HSP60, HSP70, HSP90-1, HSP90-2) in the hepatopancreas of wild (WG) and screened (SG) groups of P. trituberculatus exposed to low salinity (4 ppt).
The swimming crab, Portunus trituberculatus, is widely distributed throughout the coastal waters of Asian-Pacific nations and is an important economic species in this region. The aquaculture of swimming crabs has been plagued by problems associated with low growth rates, poor flesh quality, and weak disease resistance. To overcome these problems, selective breeding programs have been suggested as a means of genetically improving these traits in stock populations.
The Swimming crab Portunus trituberculatus (Portunidae) is an important economically food species. To provide molecular markers for P. trituberculatus, we isolated and characterized polymorphic microsatellite markers. We developed a 5'-anchored genomic library of P. trituberculatus DNA, and derived 45 positive clones. We designed 30 pairs of primers from the sequences of these clones, and 10 of which were polymorphic. The loci were screened in 31 P. trituberculatus individuals; the number of alleles ranged from 2 to 5.